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Background: Bartonella spp. infect a variety of vertebrates throughout the world, with generally high prevalence. Several Bartonella spp. are known to cause diverse clinical manifestations in humans and have been recognized as emerging pathogens. These bacteria are mainly transmitted by blood-sucking arthropods, such as fleas and lice. The role of ticks in the transmission of Bartonella spp. is unclear., Methods: A recently developed quadruplex polymerase chain reaction (PCR) amplicon next-generation sequencing approach that targets Bartonella-specific fragments on gltA, ssrA, rpoB, and groEL was applied to test host-seeking Ixodes scapularis ticks (n = 1641; consisting of 886 nymphs and 755 adults) collected in 23 states of the eastern half of the United States and Ixodes pacificus ticks (n = 966; all nymphs) collected in California in the western United States for the presence of Bartonella DNA. These species were selected because they are common human biters and serve as vectors of pathogens causing the greatest number of vector-borne diseases in the United States., Results: No Bartonella DNA was detected in any of the ticks tested by any target., Conclusions: Owing to the lack of Bartonella detection in a large number of host-seeking Ixodes spp. ticks tested across a broad geographical region, our results strongly suggest that I. scapularis and I. pacificus are unlikely to contribute more than minimally, if at all, to the transmission of Bartonella spp., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Background: A variety of tick species infest dogs and cats in North America. Although most of these species also readily feed on people, national data regarding the species and abundance of ticks on dogs and cats are lacking. Here we report a large-scale study of ticks from dogs and cats in the USA over a 12-month period., Methods: Tick submissions were invited from veterinary practices in all 50 states. Ticks were submitted with information about the pet and the attachment sites of each tick marked on a biopsy chart. Upon receipt, ticks were identified to species and stage using morphologic keys; when necessary, species identification was confirmed molecularly., Results: From February 2018 through January 2019, 10,978 ticks were submitted from 1494 dogs and 336 cats in 49 states and ticks were collected in every month. Dog and cat infestation intensities ranged from 1 to 4765 and from 1 to 38 (median = 1, mean = 6.7 and 2.6), respectively. Dogs were primarily infested with Dermacentor variabilis (532/1494; 35.6%), Ixodes scapularis (409/1494; 27.4%), Amblyomma americanum (345/1494; 23.1%) and Rhipicephalus sanguineus (172/1494; 11.5%). Cats were primarily infested with I. scapularis (156/336; 46.4%), A. americanum (99/336; 29.5%) and D. variabilis (60/336; 17.9%). Other submitted ticks included A. maculatum, Haemaphysalis longicornis, Otobius megnini, and less common Dermacentor spp. and Ixodes spp. Co-infestations were documented in 93 dogs and 14 cats. Reported attachment sites of common tick species differed. In dogs, A. americanum was most commonly attached to the abdomen, axillary, and inguinal regions; D. variabilis and I. scapularis to the head, neck, and back; and R. sanguineus to the head, neck, abdomen, legs, and feet. In cats, I. scapularis was most commonly attached to the head and A. americanum was most commonly attached to the tail and perianal region., Conclusions: These data confirm that dogs and cats in the USA are at risk of tick infestation throughout the year and that tick species present in the region have apparent attachment site preferences.

Background: Amblyomma americanum, the lone star tick, is an aggressive questing species that harbors several pathogens dangerous to humans in the United States. The Southeast in particular has large numbers of this tick due to the combined suitable climate and habitats throughout the region. No studies have estimated the underlying distribution of the lone star tick across the state of Georgia, a state where it is the dominant species encountered., Methods: Ticks were collected by flagging 198 transects of 750 m 2 at 43 state parks and wildlife management areas across the state from March to July of 2022. A suite of climate, landscape, and wildlife variables were assembled, and a logistic regression model was used to assess the association between these environmental factors and the presence of lone star ticks and to predict the distribution of these ticks across the state., Results: A total of 59/198 (30%) transects sampled contained adult or nymph A. americanum, with the majority of transects containing these ticks (54/59, 91.5%) in forested habitats. The presence of A. americanum was associated with elevation, normalized difference vegetation index (NDVI) on January 1, isothermality, temperature seasonality, and precipitation in the wettest quarter. Vast regions of central, eastern, and southern coastal Georgia (57% of the state) were categorized as suitable habitat for the lone star tick., Conclusions: This study describes the distribution of the lone star tick across the state of Georgia at a finer scale than the current county-level information available. It identifies specific variables associated with tick presence and provides a map that can be used to target areas for tick prevention messaging and awareness., (© 2024. The Author(s).)

Background: Tick-borne diseases are a growing public health threat in the United States. Despite the prevalence and rising burden of tick-borne diseases, there are major gaps in baseline knowledge and surveillance efforts for tick vectors, even among vector control districts and public health agencies. To address this issue, an online tick training course (OTTC) was developed through the Southeastern Center of Excellence in Vector-Borne Diseases (SECOEVBD) to provide a comprehensive knowledge base on ticks, tick-borne diseases, and their management. Methods: The OTTC consisted of training modules covering topics including tick biology, tick identification, tick-borne diseases, and public health, personal tick safety, and tick surveillance. The course was largely promoted to vector control specialists and public health employees throughout the Southeastern US. We collected assessment and survey data on participants to gauge learning outcomes, perceptions of the utility of knowledge gained, and barriers and facilitators to applying the knowledge in the field. Results: The OTTC was successful in increasing participants' baseline knowledge across all course subject areas, with the average score on assessment increasing from 62.6% (pre-course) to 86.7% (post-course). More than half of participants (63.6%) indicated that they would definitely use information from the course in their work. Barriers to using information identified in the delayed assessment included lack of opportunities to apply skills (18.5%) and the need for additional specialized training beyond what the OTTC currently offers (18.5%), while the main facilitator (70.4%) for applying knowledge was having opportunities at work, such as an existing tick surveillance program. Conclusions: Overall, this OTTC demonstrated capacity to improve knowledge in a necessary and underserved public health field, and more than half of participants use or plan to use the information in their work. The geographic reach of this online resource was much larger than simply for the Southeastern region for which it was designed, suggesting a much broader need for this resource. Understanding the utility and penetrance of training programs such as these is important for refining materials and assessing optimal targets for training. [ABSTRACT FROM AUTHOR]

Background: We conducted a large-scale, passive regional survey of ticks associated with wildlife of the eastern United States. Our primary goals were to better assess the current geographical distribution of exotic Haemaphysalis longicornis and to identify potential wild mammalian and avian host species. However, this large-scale survey also provided valuable information regarding the distribution and host associations for many other important tick species that utilize wildlife as hosts., Methods: Ticks were opportunistically collected by cooperating state and federal wildlife agencies. All ticks were placed in the supplied vials and host information was recorded, including host species, age, sex, examination date, location (at least county and state), and estimated tick burden. All ticks were identified to species using morphology, and suspect H. longicornis were confirmed through molecular techniques., Results: In total, 1940 hosts were examined from across 369 counties from 23 states in the eastern USA. From these submissions, 20,626 ticks were collected and identified belonging to 11 different species. Our passive surveillance efforts detected exotic H. longicornis from nine host species from eight states. Notably, some of the earliest detections of H. longicornis in the USA were collected from wildlife through this passive surveillance network. In addition, numerous new county reports were generated for Amblyomma americanum, Amblyomma maculatum, Dermacentor albipictus, Dermacentor variabilis, and Ixodes scapularis., Conclusions: This study provided data on ticks collected from animals from 23 different states in the eastern USA between 2010 and 2021, with the primary goal of better characterizing the distribution and host associations of the exotic tick H. longicornis; however, new distribution data on tick species of veterinary or medical importance were also obtained. Collectively, our passive surveillance has detected numerous new county reports for H. longicornis as well as I. scapularis. Our study utilizing passive wildlife surveillance for ticks across the eastern USA is an effective method for surveying a diversity of wildlife host species, allowing us to better collect data on current tick distributions relevant to human and animal health., (© 2022. The Author(s).)

Tick-borne diseases (TBDs) are bacterial, viral, and parasitic diseases transmitted by ticks. Viral TBDs have increased in prevalence over the last decade with many new pathogenic viruses being discovered. Doxycycline is often empirically prescribed by clinicians to treat symptomatic patients following tick bites due to suspicions of bacterial TBDs such as Rocky Mountain spotted fever, anaplasmosis, and ehrlichiosis. However, viral TBDs are included in the differential diagnosis if patients do not clinically improve following antibiotic therapy. Several viral TBDs present with dermatological manifestations. Recognizing the differences in clinical presentations of TBDs, particularly of newly emerging viral TBDs in the United States, can help physicians identify the viral TBD, and possibly rule out viral illnesses with different clinical presentations. Therefore, this review discusses clinical manifestations, with an emphasis on dermatologic manifestations of Heartland Virus, Bourbon Virus, Powassan Virus, Deer Tick Virus and Colorado Tick Fever Virus. KEY POINTS: Viral tick-borne diseases have increased in prevalence over the last decade and often have similar clinical manifestations to other tick-borne diseases, including bacterial infections. Here, we review the dermatologic manifestations of Heartland Virus (HRTV), Bourbon Virus (BRBV), Powassan Virus (POWV), Deer Tick Virus (DTV) and Colorado Tick Fever Virus (CTFV) that are important for clinicians., (© 2022. The Author(s).)

Background: The blacklegged tick, Ixodes scapularis, is the primary vector of the Lyme disease spirochete Borrelia burgdorferi in North America. Though the tick is found across the eastern United States, Lyme disease is endemic to the northeast and upper midwest and rare or absent in the southern portion of the vector's range. In an effort to better understand the tick microbiome from diverse geographic and climatic regions, we analysed the bacterial community of 115 I. scapularis adults collected from vegetation in Texas and Massachusetts, representing extreme ends of the vector's range, by massively parallel sequencing of the 16S V4 rRNA gene. In addition, 7 female I. scapularis collected from dogs in Texas were included in the study. Results: Male I. scapularis ticks had a more diverse bacterial microbiome in comparison to the female ticks. Rickettsia spp. dominated the microbiomes of field-collected female I. scapularis from both regions, as well as half of the males from Texas. In addition, the male and female ticks captured from Massachusetts contained high proportions of the pathogens Anaplasma and Borrelia, as well as the arthropod endosymbiont Wolbachia. None of these were found in libraries generated from ticks collected in Texas. Pseudomonas, Acinetobacter and Mycobacterium were significantly differently abundant (p < 0.05) between the male ticks from Massachusetts and Texas. Anaplasma and Borrelia were found in 15 and 63% of the 62 Massachusetts ticks, respectively, with a co-infection rate of 11%. Female ticks collected from Texas dogs were particularly diverse, and contained several genera including Rickettsia, Pseudomonas, Bradyrhizobium, Sediminibacterium, and Ralstonia. Conclusions: Our results indicate that the bacterial microbiomes of I. scapularis ticks vary by sex and geography, with significantly more diversity in male microbiomes compared to females. We found that sex plays a larger role than geography in shaping the composition/diversity of the I. scapularis microbiome, but that geography affects what additional taxa are represented (beyond Rickettsia) and whether pathogens are found. Furthermore, recent feeding may have a role in shaping the tick microbiome, as evident from a more complex bacterial community in female ticks from dogs compared to the wild-caught questing females. These findings may provide further insight into the differences in the ability of the ticks to acquire, maintain and transmit pathogens. Future studies on possible causes and consequences of these differences will shed additional light on tick microbiome biology and vector competence. [ABSTRACT FROM AUTHOR]

Background: In the Eastern and Upper Midwestern regions of North America, Ixodes scapularis (L.) is the most abundant tick species encountered by humans and the primary vector of B. burgdorferi, whereas in the southeastern region Amblyomma americanum (Say) is the most abundant tick species encountered by humans but cannot transmit B. burgdorferi. Surveys of Borreliae in ticks have been conducted in the southeastern United States and often these surveys identify B. lonestari as the primary Borrelia species, surveys have not included Arkansas ticks, canines, or white-tailed deer and B. lonestari is not considered pathogenic. The objective of this study was to identify Borrelia species within Arkansas by screening ticks (n = 2123), canines (n = 173), and white-tailed deer (n = 228) to determine the identity and locations of Borreliae endemic to Arkansas using PCR amplification of the flagellin (flaB) gene. Methods: Field collected ticks from canines and from hunter-killed white-tailed were identified to species and life stage. After which, ticks and their hosts were screened for the presence of Borrelia using PCR to amplify the flaB gene. A subset of the positive samples was confirmed with bidirectional sequencing. Results: In total 53 (21.2%) white-tailed deer, ten (6%) canines, and 583 (27.5%) Ixodid ticks (252 Ixodes scapularis, 161 A. americanum, 88 Rhipicephalus sanguineus, 50 Amblyomma maculatum, 19 Dermacentor variabilis, and 13 unidentified Amblyomma species) produced a Borrelia flaB amplicon. Of the positive ticks, 324 (22.7%) were collected from canines (151 A. americanum, 78 R. sanguineus, 43 I. scapularis, 26 A. maculatum, 18 D. variabilis, and 8 Amblyomma species) and 259 (37.2%) were collected from white-tailed deer (209 I. scapularis, 24 A. maculatum, 10 A. americanum, 10 R. sanguineus, 1 D. variabilis, and 5 Amblyomma species). None of the larvae were PCR positive. A majority of the flaB amplicons were homologous with B. lonestari sequences: 281 of the 296 sequenced ticks, 3 canines, and 27 deer. Only 22 deer, 7 canines, and 15 tick flaB amplicons (12 I. scapularis, 2 A. maculatum, and 1 Amblyomma species) were homologous with B. burgdorferi sequences. Conclusions: Data from this study identified multiple Borreliae genotypes in Arkansas ticks, canines and deer including B. burgdorferi and B. lonestari; however, B. lonestari was significantly more prevalent in the tick population than B. burgdorferi. Results from this study suggest that the majority of tick-borne diseases in Arkansas are not B. burgdorferi. [ABSTRACT FROM AUTHOR]

Background: The study objective was to examine cat owner ectoparasiticide purchases in the United States and estimate the impact of purchase gaps on timely ectoparasite protection administration. These purchase gaps lead to periods of time when cats are unprotected from ectoparasites., Methods: Ectoparasiticide purchase transactions for individual cats from 671 U.S. veterinary clinics from January 1, 2017 through June 30, 2019 were evaluated to determine time "gaps" between doses of ectoparasiticides purchased in a defined 12-month period. Ectoparasiticides examined were topically applied products that contained fluralaner, fipronil/(S)-methoprene/pyriproxyfen, imidacloprid/pyriproxyfen or selamectin as active ingredients. The duration of protection following administration of one dose was 8-12 weeks for the fluralaner-containing product and one month for the other products., Results: Ectoparasiticide purchase records were obtained from 114,853 cat owners and analysis found that most owners bought ≤ 6 months of protection during the year, with 61-75% (depending on the product) purchasing just 1-3 months of protection. The size of the average purchase gap was determined for all dose combinations out to 12 months of protection (5-7 doses for fluralaner and 12 doses for the other three products dosed monthly. The largest gaps occurred between the first and second doses and the second and third doses. Average purchase gaps for the four different products between doses 1 and 2 ranged from 11.2 to 13.9 weeks and between doses 2 and 3 ranged from 7.7 to 12.2 weeks. The fraction of purchases separated by gaps and the average length of the gap tended to decrease with increasing number of doses purchased. Owners purchasing the 8 to 12-week duration product containing fluralaner provided ectoparasite protection ("doses plus gap period") for a larger proportion of each 2-dose period compared with owners purchasing products administered monthly., Conclusions: When cat owners purchase flea and tick medication, gaps between subsequent purchases reduces the proportion of time ectoparasite protection can be provided. The duration of the gap between doses has an impact on the effectiveness of flea/tick medication because it inserts a period without flea and tick protection between doses of flea and tick medication. The gaps between purchases were shorter and the period of ectoparasite protection was larger for owners purchasing a 12-week product than for owners purchasing a monthly product.

Background Lyme borreliosis (LB) is the most commonly reported vector-borne disease in north temperate regions worldwide, affecting an estimated 300,000 people annually in the United States alone. The incidence of LB is correlated with human exposure to its vector, the blacklegged tick (Ixodes scapularis). To date, attempts to model tick encounter risk based on environmental parameters have been equivocal. Previous studies have not considered (1) the differences between relative humidity (RH) in leaf litter and at weather stations, (2) the RH threshold that affects nymphal blacklegged tick survival, and (3) the time required below the threshold to induce mortality. We clarify the association between environmental moisture and tick survival by presenting a significant relationship between the total number of tick adverse moisture events (TAMEs - calculated as microclimatic periods below a RH threshold) and tick abundance each year. Methods We used a 14-year continuous statewide tick surveillance database and corresponding weather data from Rhode Island (RI), USA, to assess the effects of TAMEs on nymphal populations of I. scapularis. These TAMEs were defined as extended periods of time (>8 h below 82% RH in leaf litter). We fit a sigmoid curve comparing weather station data to those collected by loggers placed in tick habitats to estimate RH experienced by nymphal ticks, and compiled the number of historical TAMEs during the 14-year record. Results The total number of TAMEs in June of each year was negatively related to total seasonal nymphal tick densities, suggesting that sub-threshold humidity episodes >8 h in duration naturally lowered nymphal blacklegged tick abundance. Furthermore, TAMEs were positively related to the ratio of tick abundance early in the season when compared to late season, suggesting that lower than average tick abundance for a given year resulted from tick mortality and not from other factors. Conclusions Our results clarify the mechanism by which environmental moisture affects blacklegged tick populations, and offers the possibility to more accurately predict tick abundance and human LB incidence. We describe a method to forecast LB risk in endemic regions and identify the predictive role of microclimatic moisture conditions on tick encounter risk. [ABSTRACT FROM AUTHOR]

Abstract' Background: For >100 years cattle production in the southern United States has been threatened by cattle fever. It is caused by an invasive parasite-vector complex that includes the protozoan hemoparasites Babesia bovis and B. bigemina, which are transmitted among domestic cattle via Rhipicephalus tick vectors of the subgenus Boophilus. In 1906 an eradication effort was started and by 1943 Boophilus ticks had been confined to a narrow tick eradication quarantine area (TEQA) along the Texas-Mexico border. However, a dramatic increase in tick infestations in areas outside the TEQA over the last decade suggests these tick vectors may be poised to re-invade the southern United States. We investigated historical and potential future distributions of climatic habitats of cattle fever ticks to assess the potential for a range expansion., Methods: We built robust spatial predictions of habitat suitability for the vector species Rhipicephalus (Boophilus) microplus and R. (B.) annulatus across the southern United States for three time periods: 1906, present day (2012), and 2050. We used analysis of molecular variance (AMOVA) to identify persistent tick occurrences and analysis of bias in the climate proximate to these occurrences to identify key environmental parameters associated with the ecology of both species. We then used ecological niche modeling algorithms GARP and Maxent to construct models that related known occurrences of ticks in the TEQA during 2001-2011 with geospatial data layers that summarized important climate parameters at all three time periods., Results: We identified persistent tick infestations and specific climate parameters that appear to be drivers of ecological niches of the two tick species. Spatial models projected onto climate data representative of climate in 1906 reproduced historical pre-eradication tick distributions. Present-day predictions, although constrained to areas near the TEQA, extrapolated well onto climate projections for 2050., Conclusions: Our models indicate the potential for range expansion of climate suitable for survival of R. microplus and R. annulatus in the southern United States by mid-century, which increases the risk of reintroduction of these ticks and cattle tick fever into major cattle producing areas.

Background: Ticks are a problem for cattle production mainly in tropical and subtropical regions, because they generate great economic losses. Acaricides and vaccines have been used to try to keep tick populations under control. This has been proven difficult given the resistance to acaricides and vaccines observed in ticks. Resistance to protein rBm86-based vaccines has been associated with the genetic diversity of Bm86 among the ectoparasite's populations. So far, neither genetic diversity, nor spatial distribution of circulating Bm86 haplotypes, have been studied within the Mexican territory. Here, we explored the genetic diversity of 125 Bm86 cDNA gene sequences from R. microplus from 10 endemic areas of Mexico by analyzing haplotype distribution patterns to help in understanding the population genetic structure of Mexican ticks. Results: Our results showed an average nucleotide identity among the Mexican isolates of 98.3%, ranging from 91.1 to 100%. Divergence between the Mexican and Yeerongpilly (the Bm86 reference vaccine antigen) sequences ranged from 3.1 to 7.4%. Based on the geographic distribution of Bm86 haplotypes in Mexico, our results suggest gene flow occurrence within different regions of the Mexican territory, and even the USA. Conclusions: The polymorphism of Bm86 found in the populations included in this study, could account for the poor efficacy of the current Bm86 antigen based commercial vaccine in many regions of Mexico. Our data may contribute towards designing new, highly-specific, Bm86 antigen vaccine candidates against R. microplus circulating in Mexico. [ABSTRACT FROM AUTHOR]

Background: Theileria orientalis is a tick-borne hemoparasite that causes anemia, ill thrift, and death in cattle globally. The Ikeda strain of T. orientalis is more virulent than other strains, leading to severe clinical signs and death of up to 5% of affected animals. Within the Asia-Pacific region, where it affects 25% of Australian cattle, T. orientalis Ikeda has a significant economic impact on the cattle industry. In 2017, T. orientalis Ikeda was detected in a cattle herd in Albermarle County, Virginia, United States. Months earlier, the U.S. was alerted to the invasion of the Asian longhorned tick, Haemaphysalis longicornis, throughout the eastern U.S. Abundant H. longicornis ticks were identified on cattle in the T. orientalis-affected herd in VA, and a subset of ticks from the environment were PCR-positive for T. orientalis Ikeda. A strain of T. orientalis from a previous U.S. outbreak was not transmissible by H. longicornis; however, H. longicornis is the primary tick vector of T. orientalis Ikeda in other regions of the world. Thus, the objective of this study was to determine whether invasive H. longicornis ticks in the U.S. are competent vectors of T. orientalis Ikeda., Methods: Nymphal H. longicornis ticks were fed on a splenectomized calf infected with the VA-U.S.-T. orientalis Ikeda strain. After molting, a subset of adult ticks from this cohort were dissected, and salivary glands assayed for T. orientalis Ikeda via qPCR. The remaining adult ticks from the group were allowed to feed on three calves. Calves were subsequently monitored for T. orientalis Ikeda infection via blood smear cytology and PCR., Results: After acquisition feeding on a VA-U.S.-T. orientalis Ikeda-infected calf as nymphs, a subset of molted adult tick salivary glands tested positive by qPCR for T. orientalis Ikeda. Adult ticks from the same cohort successfully transmitted T. orientalis Ikeda to 3/3 naïve calves, each of which developed parasitemia reaching 0.4-0.9%., Conclusions: Our findings demonstrate that U.S. H. longicornis ticks are competent vectors of the VA-U.S.-T. orientalis Ikeda strain. This data provides important information for the U.S. cattle industry regarding the potential spread of this parasite and the necessity of enhanced surveillance and control measures.

Background: Both incidence and geographical range of tick-borne disease has increased across the USA. Similar to people, dogs are hosts for Anaplasma spp., Babesia spp., Ehrlichia spp. and Borrelia burgdorferi. Dogs also share our homes and beds, making them both a sentinel for the ticks in our backyards but also increasing our exposure to ticks. Measures to better track, prevent, and/or treat tick-borne diseases in companion animals can lead to better control and prevention of human tick-borne disease. This study identifies demographic and co-infection risk factors for canine seropositivity to tick-borne infections in a cohort of hunting dogs across the USA., Results: Human patterns of tick-borne disease co-infection in the USA have been predominantly driven by the geographical distribution of the tick vector. Dogs who tested seropositive for Anaplasma spp. were 1.40 times more likely (P = 0.0242) to also test seropositive for Babesia spp. and vice versa (1.60 times more likely, P = 0.0014). Dogs living in the West had 5% lower risk (P = 0.0001) for Ehrlichia spp. seropositivity compared to other regions. Controlling for age and Anaplasma spp. seroprevalence, dogs in all three other regions were 2.30 times more likely (P = 0.0216) to test seropositive for B. burgdorferi than dogs in the West. Dogs seropositive for B. burgdorferi were 1.60 times more likely (P = 0.0473) to be seropositive for Anaplasma spp., Conclusions: Tick geographical distributions have a prominent impact on the regional distribution of hunting dog exposure to tick-borne diseases. Education concerning regional tick prevalence and disease risk is important for everyone, but particularly dog owners, regarding ticks in their region and protection from infection and co-infection of tick-borne pathogens as they travel or move with their dogs. Dogs are sentinel species for human exposure to ticks, and as such surveillance of canine tick-borne infections and understanding the probability that these infections might be seen together as co-infections helps predict emerging areas where people are more likely to be exposed as well.

Background: Babesia are emerging health threats to humans and animals in the United States. A collaborative effort of multiple disciplines to attain optimal health for people, animals and our environment, otherwise known as the One Health concept, was taken during a research workshop held in April 2009 to identify gaps in scientific knowledge regarding babesioses. The impetus for this analysis was the increased risk for outbreaks of bovine babesiosis, also known as Texas cattle fever, associated with the re-infestation of the U.S. by cattle fever ticks. Results: The involvement of wildlife in the ecology of cattle fever ticks jeopardizes the ability of state and federal agencies to keep the national herd free of Texas cattle fever. Similarly, there has been a progressive increase in the number of cases of human babesiosis over the past 25 years due to an increase in the white-tailed deer population. Human babesiosis due to cattle-associated Babesia divergens and Babesia divergens-like organisms have begun to appear in residents of the United States. Research needs for human and bovine babesioses were identified and are presented herein. Conclusions: The translation of this research is expected to provide veterinary and public health systems with the tools to mitigate the impact of bovine and human babesioses. However, economic, political, and social commitments are urgently required, including increased national funding for animal and human Babesia research, to prevent the reestablishment of cattle fever ticks and the increasing problem of human babesiosis in the United States. [ABSTRACT FROM AUTHOR]

Malaria and Lyme disease were the largest vector-borne epidemics in recent US history. Malaria, a mosquito-borne disease with intense transmission, had higher morbidity and mortality, whereas Lyme and other tick-borne diseases are more persistent in the environment. The responses to these two epidemics were markedly different. The anti-malaria campaign involved large-scale public works eradicating the disease within two decades. In contrast, Lyme disease control and prevention focused on the individual, advocating personal protection and backyard control, with the disease incidence steeply increasing since 1980s. Control of Lyme and other tick-borne diseases will require a paradigm shift emphasizing measures to reduce tick and host (deer) populations and a substantial R&D effort. These steps will require changing the political climate, perceptions and opinions to generate support among governmental levels and the general public. Such support is essential for providing a real solution to one of the most intractable contemporary public health problems.

Background: Safe and effective flea and tick treatment options for cats are important in companion animal practice because of feline ectoparasite infestation prevalence and the potential for parasitic disease transmission. Retrospective cat owner purchasing transactions at United States of America (USA) veterinary clinics were obtained for three topical feline flea and tick ectoparasiticides. One medication, fluralaner, had a 12-week redosing interval, while two other medications (fipronil/s-methoprene/pyriproxyfen; imidacloprid/pyriproxyfen) were approved for monthly redosing. The annual number of doses purchased by cat owners was determined for each of the three medications and then compared between medications. The objective was to evaluate whether 12-week retreatment intervals resulted in a different duration of coverage compared to monthly treatments for ectoparasiticide products., Methods: Study results were obtained by analyzing the transactional records from a commercial database derived from veterinary practice management software. The study database consisted of cat owner purchasing records from January 2017 through June 2019 from 671 veterinary practices representing 41,630 cats., Results: Cat owners purchased an average of 1.5 doses of fluralaner per year which, based on a 12-week redosing interval, provides 4.2 months of treatment coverage. Cat owners who used monthly flea and tick medications respectively purchased 3.6 months (fipronil/s-methoprene/pyriproxyfen combination) and 2.8 months (imidacloprid/pyriproxyfen) annually of each of the two medications. Average yearly cat owner purchases of fluralaner provide a significantly longer duration of coverage than for cat owners purchasing fipronil/s-methoprene/pyriproxyfen (17% more) or imidacloprid/pyriproxyfen (50% more)., Conclusions: Cat owners who obtained a flea and tick treatment with a 12-week redosing interval (fluralaner) protected their cats for up to 17% or 50% longer duration each year, respectively, compared to the duration of protection obtained by cat owners who used a medication re-dosed monthly. Cat owners should increase their duration of flea and tick coverage to come closer to achieving veterinary recommendations.

Background: Lyme disease, caused primarily by Borrelia burgdorferi sensu stricto, is the most prevalent vector-borne disease in the United States. Treatment of rodent pathogen reservoirs with an oral acaricide may suppress the production of infected host-seeking ticks posing a risk for human infection. A previous study showed that an oral fipronil bait effectively controlled larval Ixodes scapularis ticks on white-footed mice (Peromyscus leucopus) up to 15 days post-bait exposure. The present study expands upon this finding by exposing group-housed white-footed mice to fipronil bait under simulated field conditions prior to tick infestation. Methods: Mice (n = 80) were housed in groups of 10 within large enclosures and offered a choice between fipronil bait within a commercial bait station and an alternative diet. The mice were assigned to two treatment groups and two control groups to undergo bait exposure durations of either 24 h (reduced) or 168 h (extended). Groups were further differentiated by the time point post-bait exposure when larval ticks were applied to mice within feeding capsules (reduced day 1, day 15; extended day 21, day 35). For 4 days post-tick introduction, attached larvae were observed by microscopy and replete larvae were recovered. Replete larvae were monitored for molting success. Plasma was collected from all treatment group mice to obtain fipronil plasma concentrations (CP). Results: The fipronil bait (0.005% fipronil) was palatable and controlled larval ticks on white-footed mice when presented under simulated field conditions. Efficacy in preventing attached larvae from feeding to repletion was 100% (day 1), 89.0% (day 15), 85.8% (day 21), and 75.2% (day 35). When also considering molting success, the fipronil bait prevented 100% (day 1), 91.1% (day 15), 91.7% (day 21), and 82.5% (day 35) of larvae attaching to mice from molting. The mean CP per mouse was 191.5 ng/ml (day 1), 29.4 ng/ml (day 15), 10.6 ng/ml (day 21), and 1.0 ng/ml (day 35). Conclusions: The results suggest that fipronil bait will be consumed by white-footed mice in the presence of an alternative diet, and effectively control larval ticks on treated mice. A field trial is needed to confirm the results of this study. Low-dose fipronil bait may provide a cost-effective means of controlling blacklegged ticks to be integrated into tick management programs. [ABSTRACT FROM AUTHOR]

Background: People with occupations that require them to spend time working outdoors in suitable tick habitats are predicted to be at an increased risk for tick-borne diseases (TBDs). However, few studies have assessed the risks of outdoor employees in the United States.Methods: We conducted a cross-sectional survey to collect data on exposure to ticks and TBD infections among U.S. Forest Service employees in a high TBD incidence region of northern Wisconsin, and to examine employee knowledge, attitudes, and practices (KAPs) regarding TBDs to help guide future education and prevention programs. Chi-square contingency tables, calculations of odds ratios, and logistic regression models were used to identify associations among self-reported employee factors, the proportion of correctly answered knowledge questions, their ranked concern for TBDs, adherence to practicing preventive behaviors, and willingness to pay for protective measures.Results: Ninety-five employees completed the survey. Nearly all respondents (97%) reported recent tick exposure, with 27% reporting encountering 10 or more ticks per week during peak tick season. Employee knowledge of TBD was high (median score: 80% correct). Fifty-nine percent of respondents had high concern for TBDs, and there was high adherence to conducting body checks for ticks (83% reported always doing them), but only moderate use of tick repellents (24% reported always and 60% reported occasionally using). High concern for TBD (adjusted odds ratio (aOR) = 6.32 [95% confidence intervals, 1.97-20.28]), a history of TBD diagnosis (aOR = 5.88 [1.41-24.55]), and older age (≥ 46 years) (aOR = 3.29 [1.00-10.84]) were positively associated with high practice adherence. Respondents suggested they would be willing to pay for personal protective methods and get a hypothetical vaccine for Lyme disease, but not community-wide efforts to control ticks.Conclusions: Our study provides evidence that U.S. Forest Service employees in Wisconsin represent a high risk group for TBD, and despite relatively high TBD knowledge and engagement in tick protection activities, efforts are needed to reduce their risks for tick bites. More generally, our findings suggest that studies to better understand the factors related to the adoption and effectiveness of public health interventions are needed. [ABSTRACT FROM AUTHOR]

Background: Veterinary clinic transaction records from the USA were examined to determine dog owner purchase patterns for three prescription ectoparasiticides. In-clinic purchases of formulations of fluralaner (with 12-week duration per dose) were compared with dog owner purchases of afoxolaner and spinosad (both with 4 week duration per dose) in a population of 231,565 dogs over a 12 month period. Prior studies in human and animal medicine have suggested that patients more closely adhere to prescriber dosing recommendations when they receive a longer-duration medication., Results: Veterinary clinic transaction records were examined for the period June 2014 through March 2017 using records from approximately 650 veterinary clinics. Ectoparasiticide purchase patterns were compared for two products (afoxalaner and spinosad) with monthly dosing and one product (fluralaner) with an extended (12 week) dosing interval. The average dog owner who obtained fluralaner purchased significantly more months of flea/tick protection (5.7 months) over the 12-month study period than the average dog owner that selected either afoxolaner (4.6 months) or spinosad (3.3 months). The proportion of dog owners who obtained only one dose of ectoparasiticide per 12-month period was 42% for fluralaner, 30% for afoxolaner and 37% for spinosad. The proportion of dog owners who obtained 2 doses or less per 12-month period was 67% for fluralaner, 52% for afoxoalaner and 67% for spinosad. Owners that obtained fluralaner were significantly more likely to obtain 7.0-12.0 months of flea and tick protection and significantly less likely to purchase 1.0-6.9 months compared with dog owners who purchased afoxolaner or spinosad., Conclusions: Dog owners who obtained a flea and tick medication with a longer duration of action acquired significantly more months of protection in a year than dog owners who obtained shorter duration (1 month) products. Dog owners were better able to adhere to veterinary recommendations on ectoparasites control with a longer-acting flea/tick medication.

Background Acaricide resistant Rhipicephalus microplus populations have become a major problem for many cattle producing areas of the world. Pyrethroid resistance in arthropods is typically associated with mutations in domains I, II, III, and IV of voltage-gated sodium channel genes. In R. microplus, known resistance mutations include a domain II change (C190A) in populations from Australia, Africa, and South America and a domain III mutation (T2134A) that only occurs in Mexico and the U.S. Methods We investigated pyrethroid resistance in cattle fever ticks from Texas and Mexico by estimating resistance levels in field-collected ticks using larval packet discriminating dose (DD) assays and identifying single nucleotide polymorphisms (SNPs) in the para-sodium channel gene that associated with resistance. We then developed qPCR assays for three SNPs and screened a larger set of 1,488 R. microplus ticks, representing 77 field collections and four laboratory strains, for SNP frequency. Results We detected resistance SNPs in 21 of 68 U.S. field collections and six of nine Mexico field collections. We expected to identify the domain III SNP (T2134A) at a high frequency; however, we only found it in three U.S. collections. A much more common SNP in the U.S. (detected in 19 of 21 field collections) was the C190A domain II mutation, which has never before been reported from North America. We also discovered a novel domain II SNP (T170C) in ten U.S. and two Mexico field collections. The T170C transition mutation has previously been associated with extreme levels of resistance (super-knockdown resistance) in insects. We found a significant correlation (r = 0.81) between the proportion of individuals in field collections that carried any two resistance SNPs and the percent survivorship of F1 larvae from these collections in DD assays. This relationship is accurately predicted by a simple linear regression model (R2 = 0.6635). Conclusions These findings demonstrate that multiple mutations in the para-sodium channel gene independently associate with pyrethroid resistance in R. microplus ticks, which is likely a consequence of human-induced selection. [ABSTRACT FROM AUTHOR]

The Companion Animal Parasite Council hosted a meeting to identify quantifiable factors that can influence the prevalence of tick-borne disease agents among dogs in North America. This report summarizes the approach used and the factors identified for further analysis with mathematical models of canine exposure to tick-borne pathogens.

Background: This study evaluated the exposure of dogs to three different Ehrlichia spp. in the south and central regions of the United States where vector-borne disease prevalence has been previously difficult to ascertain, particularly beyond the metropolitan areas., Methods: Dog blood samples (n = 8,662) were submitted from 14 veterinary colleges, 6 private veterinary practices and 4 diagnostic laboratories across this region. Samples were tested for E. canis, E. chaffeensis and E. ewingii specific antibodies using peptide microtiter ELISAs., Results: Overall, E. canis, E. chaffeensis and E. ewingii seroprevalence was 0.8%, 2.8%, and 5.1%, respectively. The highest E. canis seroprevalence (2.3%) was found in a region encompassing Arkansas, Louisiana, Oklahoma, Tennessee and Texas. E. chaffeensis seroreactivity was 6.6% in the central region (Arkansas, Kansas, Missouri, and Oklahoma) and 4.6% in the southeast region (Georgia, Maryland, North Carolina, South Carolina, Tennessee and Virginia). Seroreactivity to E. ewingii was also highest in the central region (14.6%) followed by the southeast region (5.9%). The geospatial pattern derived from E. chaffeensis and E. ewingii seropositive samples was similar to previous reports based on E. chaffeensis seroreactivity in white-tailed deer and the distribution of human monocytic ehrlichiosis (HME) cases reported by the CDC., Conclusions: The results of this study provide the first large scale regional documentation of exposure to E. canis, E. chaffeensis and E. ewingii in pet dogs, highlighting regional differences in seroprevalence and providing the basis for heightened awareness of these emerging vector-borne pathogens by veterinarians and public health agencies.

Background: Disease maps are used increasingly in the health sciences, with applications ranging from the diagnosis of individual cases to regional and global assessments of public health. However, data on the distributions of emerging infectious diseases are often available from only a limited number of samples. We compared several spatial modelling approaches for predicting the geographic distributions of two tick-borne pathogens: Ehrlichia chaffeensis, the causative agent of human monocytotropic ehrlichiosis, and Anaplasma phagocytophilum, the causative agent of human granulocytotropic anaplasmosis. These approaches extended environmental modelling based on logistic regression by incorporating both spatial autocorrelation (the tendency for pathogen distributions to be clustered in space) and spatial heterogeneity (the potential for environmental relationships to vary spatially)., Results: Incorporating either spatial autocorrelation or spatial heterogeneity resulted in substantial improvements over the standard logistic regression model. For E. chaffeensis, which was common within the boundaries of its geographic range and had a highly clustered distribution, the model based only on spatial autocorrelation was most accurate. For A. phagocytophilum, which has a more complex zoonotic cycle and a comparatively weak spatial pattern, the model that incorporated both spatial autocorrelation and spatially heterogeneous relationships with environmental variables was most accurate., Conclusion: Spatial autocorrelation can improve the accuracy of predictive disease risk models by incorporating spatial patterns as a proxy for unmeasured environmental variables and spatial processes. Spatial heterogeneity can also improve prediction accuracy by accounting for unique ecological conditions in different regions that affect the relative importance of environmental drivers on disease risk.

Background: Ticks are regarded as the most relevant vectors of disease-causing pathogens in domestic and wild animals. The cattle tick, Rhipicephalus (Boophilus) microplus, hinders livestock production in tropical and subtropical parts of the world where it is endemic. Tick microbiomes remain largely unexplored. The objective of this study was to explore the R. microplus microbiome by applying the bacterial 16S tag-encoded FLX-titanium amplicon pyrosequencing (bTEFAP) technique to characterize its bacterial diversity. Pyrosequencing was performed on adult males and females, eggs, and gut and ovary tissues from adult females derived from samples of R. microplus collected during outbreaks in southern Texas. Results: Raw data from bTEFAP were screened and trimmed based upon quality scores and binned into individual sample collections. Bacteria identified to the species level include Staphylococcus aureus, Staphylococcus chromogenes, Streptococcus dysgalactiae, Staphylococcus sciuri, Serratia marcescens, Corynebacterium glutamicum, and Finegoldia magna. One hundred twenty-one bacterial genera were detected in all the life stages and tissues sampled. The total number of genera identified by tick sample comprised: 53 in adult males, 61 in adult females, 11 in gut tissue, 7 in ovarian tissue, and 54 in the eggs. Notable genera detected in the cattle tick include Wolbachia, Coxiella, and Borrelia. The molecular approach applied in this study allowed us to assess the relative abundance of the microbiota associated with R. microplus. Conclusions: This report represents the first survey of the bacteriome in the cattle tick using non-culture based molecular approaches. Comparisons of our results with previous bacterial surveys provide an indication of geographic variation in the assemblages of bacteria associated with R. microplus. Additional reports on the identification of new bacterial species maintained in nature by R. microplus that may be pathogenic to its vertebrate hosts are expected as our understanding of its microbiota expands. Increased awareness of the role R. microplus can play in the transmission of pathogenic bacteria will enhance our ability to mitigate its economic impact on animal agriculture globally. This recognition should be included as part of analyses to assess the risk for re-invasion of areas like the United States of America where R. microplus was eradicated. [ABSTRACT FROM AUTHOR]

Background: Ixodes scapularis, commonly known as the blacklegged or deer tick, is the main vector of Lyme disease in the United States. Recent progress in transcriptome research has uncovered hundreds of different proteins expressed in the salivary glands of hard ticks, the majority of which have no known function, and include many novel protein families. We recently identified transcripts coding for two putative cytosolic sulfotransferases in these ticks which recognized phenolic monoamines as their substrates. In this current study, we characterize the genetic expression of these two cytosolic sulfotransferases throughout the tick life cycle as well as the enzymatic properties of the corresponding recombinant proteins. Interestingly, the resultant recombinant proteins showed sulfotransferase activity against both neurotransmitters dopamine and octopamine. Results: The two sulfotransferase genes were coded as Ixosc SULT 1 & 2 and corresponding proteins were referred as Ixosc Sult 1 and 2. Using gene-specific primers, the sulfotransferase transcripts were detected throughout the blacklegged tick life cycle, including eggs, larvae, nymphs, adult salivary glands and adult midgut. Notably, the mRNA and protein levels were altered upon feeding during both the larval and nymphal life stages. Quantitative PCR results confirm that Ixosc SULT1 was statistically increased upon blood feeding while Ixosc SULT 2 was decreased. This altered expression led us to further characterize the function of these proteins in the Ixodid tick. The sulfotransferase genes were cloned and expressed in a bacterial expression system, and purified recombinant proteins Ixosc Sult 1(R) and 2(R) showed sulfotransferase activity against neurotransmitters dopamine and octopamine as well as the common sulfotransferase substrate p-nitrophenol. Thus, dopamine- or octopaminesulfonation may be involved in altering the biological signal for salivary secretion in I. scapularis. Conclusions: Collectively, these results suggest that a function of Ixosc Sult 1 and Sult 2 in Ixodid tick salivary glands may include inactivation of the salivation signal via sulfonation of dopamine or octopamine. [ABSTRACT FROM AUTHOR]

Background: The Cumberland Gap Region (CGR) of the United States is a natural corridor between the southeastern, northeastern, and midwestern regions of the country. CGR has also many species of ticks and mosquitos that serve as competent vectors for important animal and human pathogens. In this study, we tested dogs from six different animal shelters in the CGR for Rocky Mountain spotted fever (RMSF), anaplasmosis, Lyme disease, canine ehrlichiosis and canine heartworm disease. Results: Sera from 157 shelter dogs were tested for antibodies to RMSF agent, Rickettsia rickettsii, using an indirect immunofluorescence assay. Sixty-six dogs (42.0%) were positive for either IgM or IgG, or both IgM and IgG antibodies to R. rickettsii. Moreover, the same set of sera (n = 157) plus an and additional sera (n = 75) from resident dogs at the same shelters were tested using the SNAP 4Dx Plus. Of 232 dogs tested, two (0.9%) were positive for antibodies to Anaplasma phagocytophilum/A. platys, nine (3.9%) were positive for antibodies to Borrelia burgdorferi, 23 (9.9%) for positive for antibodies to Ehrlichia canis/E. ewingii, and 13 (5.6%) were positive for Dirofilaria immitis antigen. Co-infection with two or more etiologic agents was detected in five animals. Three dogs had antibodies to both B. burgdorferi and E. canis/E. ewingii, and two dogs were positive for D. immitis antigen and antibodies to B. burgdorferi and E. canis/E. ewingii. Conclusions: Shelter dogs in the CGR are exposed to a number of important vector-borne pathogens. Further studies are required to ascertain the roles these animals play in maintenance and transmission of these pathogens. [ABSTRACT FROM AUTHOR]

Background: The vast majority of vector-borne diseases in the USA are associated with mosquitoes or ticks. Mosquito control is often conducted as part of community programs run by publicly-funded entities. By contrast, tick control focuses primarily on individual residential properties and is implemented predominantly by homeowners and the private pest control firms they contract. We surveyed publicly-funded vector control programs (VCPs), presumed to focus mainly on mosquitoes, to determine what tick-related services they currently offer, and their interest in and capacity to expand existing services or provide new ones., Methods: We distributed a survey to VCPs in the Northeast, Upper Midwest and Pacific Coast states of the USA, where humans are at risk for bites by tick vectors (Ixodes scapularis or Ixodes pacificus) of agents causing Lyme disease and other tick-borne diseases. The data we report are based on responses from 118 VCPs engaged in vector control and with at least some activities focused on ticks., Results: Despite our survey targeting geographic regions where ticks and tick-borne diseases are persistent and increasing public health concerns, only 11% (12/114) of VCPs reported they took direct action to suppress ticks questing in the environment. The most common tick-related activities conducted by the VCPs were tick bite prevention education for the public (70%; 75/107 VCPs) and tick surveillance (48%; 56/116). When asked which services they would most likely include as part of a comprehensive tick management program, tick bite prevention education (90%; 96/107), tick surveillance (89%; 95/107) and tick suppression guidance for the public (74%; 79/107) were the most common services selected. Most VCPs were also willing to consider engaging in activities to suppress ticks on public lands (68%; 73/107), but few were willing to consider suppressing ticks on privately owned land such as residential properties (15%; 16/107). Across all potential tick-related services, funding was reported as the biggest obstacle to program expansion or development, followed by personnel., Conclusions: Considering the hesitancy of VCPs to provide tick suppression services on private properties and the high risk for tick bites in peridomestic settings, suppression of ticks on residential properties by private pest control operators will likely play an important role in the tick suppression landscape in the USA for the foreseeable future. Nevertheless, VCPs can assist in this effort by providing locally relevant guidelines to homeowners and private pest control firms regarding best practices for residential tick suppression efforts and associated efficacy evaluations. Publicly-funded VCPs are also well positioned to educate the public on personal tick bite prevention measures and to collect tick surveillance data that provide information on the risk of human encounters with ticks within their jurisdictions., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Background: Lyme disease (LD) is the most common tick-borne disease in the United States and in Europe. The aim of this study was to examine knowledge, perceived risk, feelings of anxiety, and behavioral responses of the general public in relation to tick bites and LD in the Netherlands. Methods: From a representative Internet panel a random sample was drawn of 550 panel members aged 18 years and older (8-15 November 2010) who were invited to complete an online questionnaire. Results: Response rate (362/550, 66%). This study demonstrates that knowledge, level of concern, and perceived efficacy are the main determinants of preventive behavior. 35% (n = 125/362) of the respondents reported a good general knowledge of LD. While 95% (n = 344/362) perceived LD as severe or very severe, the minority (n = 130/362, 36%) perceived their risk of LD to be low. Respondents were more likely to check their skin after being outdoors and remove ticks if necessary, than to wear protective clothing and/or use insect repellent skin products. The percentage of respondents taking preventive measures ranged from 6% for using insect repellent skin products, to 37% for wearing protective clothing. History of tick bites, higher levels of knowledge and moderate/high levels of worry were significant predictors of checking the skin. Significant predictors of wearing protective clothing were being unemployed/retired, higher knowledge levels, higher levels of worry about LD and higher levels of perceived efficacy of wearing protective clothing. Conclusions: Prevention programs targeting tick bites and LD should aim at influencing people's perceptions and increasing their knowledge and perceived efficacy of protective behavior. This can be done by strengthening motivators (e.g. knowledge, concern about LD, perceived efficacy of wearing protective clothing) and removing barriers (e.g. low perceived personal risk, not knowing how to recognize a tick). The challenge is to take our study findings and translate them into appropriate prevention strategies. [ABSTRACT FROM AUTHOR]

Background: Lyme disease is one of the most commonly reported infectious diseases in the United States (US), accounting for more than 90 % of all vector-borne diseases in North America. Objective: In this paper, self-reported tweets on Twitter were analyzed in order to predict potential Lyme disease cases and accurately assess incidence rates in the US. Methods: The study was done in three stages: (1) Approximately 1.3 million tweets were collected and pre-processed to extract the most relevant Lyme disease tweets with geolocations. A subset of tweets were semi-automatically labelled as relevant or irrelevant to Lyme disease using a set of precise keywords, and the remaining portion were manually labelled, yielding a curated labelled dataset of 77, 500 tweets. (2) This labelled data set was used to train, validate, and test various combinations of NLP word embedding methods and prominent ML classification models, such as TF-IDF and logistic regression, Word2vec and XGboost, and BERTweet, among others, to identify potential Lyme disease tweets. (3) Lastly, the presence of spatio-temporal patterns in the US over a 10-year period were studied. Results: Preliminary results showed that BERTweet outperformed all tested NLP classifiers for identifying Lyme disease tweets, achieving the highest classification accuracy and F1-score of 90 % . There was also a consistent pattern indicating that the West and Northeast regions of the US had a higher tweet rate over time. Conclusions: We focused on the less-studied problem of using Twitter data as a surveillance tool for Lyme disease in the US. Several crucial findings have emerged from the study. First, there is a fairly strong correlation between classified tweet counts and Lyme disease counts, with both following similar trends. Second, in 2015 and early 2016, the social media network like Twitter was essential in raising popular awareness of Lyme disease. Third, counties with a high incidence rate were not necessarily related with a high tweet rate, and vice versa. Fourth, BERTweet can be used as a reliable NLP classifier for detecting relevant Lyme disease tweets. [ABSTRACT FROM AUTHOR]

Domestic dogs are susceptible to numerous vector-borne pathogens that are of significant importance for their health. In addition to being of veterinary importance, many of these pathogens are zoonotic and thus may pose a risk to human health. In the USA, owned dogs are commonly screened for exposure to or infection with several canine vector-borne pathogens. Although the screening data are widely available to show areas where infections are being diagnosed, testing of owned dogs is expected to underestimate the actual prevalence in dogs that have no access to veterinary care. The goal of this study was to measure the association between the widely available data from a perceived low-risk population with temporally and spatially collected data from shelter-housed dog populations. These data were then used to extrapolate the prevalence in dogs that generally lack veterinary care. The focus pathogens included Dirofilaria immitis, Ehrlichia spp., Anaplasma spp., and Borrelia burgdorferi. There was a linear association between the prevalence of selected vector-borne pathogens in shelter-housed and owned dog populations and, generally, the data suggested that prevalence of heartworm (D. immitis) infection and seroprevalence of Ehrlichia spp. and B. burgdorferi are higher in shelter-housed dogs, regardless of their location, compared with the owned population. The seroprevalence of Anaplasma spp. was predicted to be higher in areas that have very low to low seroprevalence, but unexpectedly, in areas of higher seroprevalence within the owned population, the seroprevalence was expected to be lower in the shelter-housed dog population. If shelters and veterinarians make decisions to not screen dogs based on the known seroprevalence of the owned group, they are likely underestimating the risk of exposure. This is especially true for heartworm. With this new estimate of the seroprevalence in shelter-housed dogs throughout the USA, shelters and veterinarians can make evidence-based informed decisions on whether testing and screening for these pathogens is appropriate for their local dog population. This work represents an important step in understanding the relationships in the seroprevalences of vector-borne pathogens between shelter-housed and owned dogs, and provides valuable data on the risk of vector-borne diseases in dogs., (© 2023. The Author(s).)

Background: Dogs in the United States are hosts to a diverse range of ticks and tick-borne pathogens, including A. phagocytophilum, an important emerging canine and human pathogen. Previously, a Companion Animal Parasite Council (CAPC)-sponsored workshop proposed factors purported to be associated with the infection risk for ticktransmitted pathogens in dogs in the United States, including climate conditions, socioeconomic characteristics, local topography, and vector distribution. Methods: Approximately four million test results from routine veterinary diagnostic tests from 2011-2013, which were collected on a county level across the contiguous United States, are statistically analyzed with the proposed factors via logistic regression and generalized estimating equations. Spatial prevalence maps of baseline Anaplasma spp. prevalence are constructed from Kriging and head-banging smoothing methods. Results: All of the examined factors, with the exception of surface water coverage, were significantly associated with Anaplasma spp. prevalence. Overall, Anaplasma spp. prevalence increases with increasing precipitation and forestation coverage and decreases with increasing temperature, population density, relative humidity, and elevation. Interestingly, socioeconomic status and deer/vehicle collisions were positively and negatively correlated with canine Anaplasma seroprevalence, respectively. A spatial map of the canine Anaplasma hazard is an auxiliary product of the analysis. Anaplasma spp. prevalence is highest in New England and the Upper Midwest. Conclusions: The results from the two posited statistical models (one that contains an endemic areas assumption and one that does not) are in general agreement, with the major difference being that the endemic areas model estimates a larger prevalence in Western Texas, New Mexico, and Colorado. As A. phagocytophilum is zoonotic, the results of this analysis could also help predict areas of high risk for human exposure to this pathogen. [ABSTRACT FROM AUTHOR]

Background: Hepatozoon spp. are apicomplexan parasites known to cause musculoskeletal disease in a variety of animals. Two species are known to infect wild and domestic canids in the US: Hepatozoon canis and H. americanum., Methods: In this study, blood, heart, and/or spleen samples were collected from 278 wild canids (180 coyotes, 93 red foxes, and 5 gray foxes) in the eastern US and tested via PCR for Hepatozoon. Histology slides of heart and skeletal muscle were assessed for Hepatozoon cysts and associated inflammation when fresh tissue was available (n = 96)., Results: Hepatozoon spp. were found in 24.2% (59/278) of individuals, with Hepatozoon canis in 14.0% (34/278) and H. americanum in 10.7% (26/278). One coyote was positive for both H. canis and H. americanum. Foxes were more likely to be positive for H. canis than coyotes (23% and 7% respectively, P = 0.0008), while only coyotes were positive for H. americanum. Of the eight sampled states, H. canis was present in six (Louisiana, North Carolina, Pennsylvania, South Carolina, Tennessee, and Virginia) while H. americanum was found in two southern states (South Carolina and Louisiana). Infection status was positively correlated with myositis and myocarditis, and heart or muscle cysts were found in 83% (5/6) of H. americanum-positive coyotes., Conclusion: This survey showed a moderate prevalence of H. canis and H. americanum in states where the parasite was previously unrecorded including South Carolina and Pennsylvania., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Background: The cat flea (Ctenocephalides felis), a parasite commonly found on both dogs and cats, is a competent vector for several zoonotic pathogens, including Dipylidium caninum (tapeworms), Bartonella henselae (responsible for cat scratch disease) and Rickettsia felis (responsible for flea-borne spotted fever). Veterinarians recommend that both cats and dogs be routinely treated with medications to prevent flea infestation. Nevertheless, surveys suggest that nearly one third of pet owners do not routinely administer appropriate preventatives. Methods: A mathematical model based on weighted averaging over time is developed to predict outdoor flea activity from weather conditions for the contiguous United States. This 'nowcast' model can be updated in real time as weather conditions change and serves as an important tool for educating pet owners about the risks of flea-borne disease. We validate our model using Google Trends data for searches for the term 'fleas.' This Google Trends data serve as a proxy for true flea activity, as validating the model by collecting fleas over the entire USA is prohibitively costly and time-consuming. Results: The average correlation (r) between the nowcast outdoor flea activity predictions and the Google Trends data was moderate: 0.65, 0.70, 0.66, 0.71 and 0.63 for 2016, 2017, 2018, 2019 and 2020, respectively. However, there was substantial regional variation in performance, with the average correlation in the East South Atlantic states being 0.81 while the average correlation in the Mountain states was only 0.45. The nowcast predictions displayed strong seasonal and geographic patterns, with predicted activity generally being highest in the summer months. Conclusions: The nowcast model is a valuable tool by which to educate pet owners regarding the risk of fleas and flea-borne disease and the need to routinely administer flea preventatives. While it is ideal for domestic cats and dogs to on flea preventatives year-round, many pets remain vulnerable to flea infestation. Alerting pet owners to the local increased risk of flea activity during certain times of the year may motivate them to administer appropriate routine preventives. [ABSTRACT FROM AUTHOR]

Background: In the United States (US), many obstetrics & gynecology (OB-GYN) trainees feel unprepared to care for lesbian, gay, bisexual, transgender, queer, and intersex (LGBTQI) individuals, but interest in this topic is rising. Residency program websites are one way that directors can advertise whether this training is offered within their program. We aimed to describe the extent to which LGBTQI content is currently featured on OB-GYN residency websites across the country. Methods: We identified all OB-GYN residency programs in the United States using a publicly available database. We systematically searched for select LGBTQI keywords on program websites. We collected data on mentions of LGBTQI didactics and rotations. We also searched whether LGTBQI keywords were included in diversity, equity, and inclusion (DEI) statements. We used multivariable logistic regression to compare the characteristics of programs that do and do not include this content. We used STATA SE Version 16.0 for all analyses and set the level of significance at 5%. Results: We included 287/295 US OB-GYN residency programs in our analysis (97.3%) and excluded 8 that did not have websites. We identified any LGBTQI content on 50 program websites (17.4%), and specific mention of didactics or rotations on 8 websites (2.8%). On multivariable analysis, programs in the West were more likely to include any LGBTQI content compared to programs in the South (OR 2.81, 95%CI 1.04–7.63), as were programs with 1 or 2 fellowships (OR 3.41, 95%CI 1.43–8.14) or 3 or more fellowships (OR 4.85, 95%CI 2.03–11.57) compared to those without fellowships. Programs in departments led by female chairs were also more likely to include LBTQI content (OR 3.18, 95%CI 1.55–6.51). Conclusions: Academic programs, West Coast programs, and those with departments led by female chairs are more likely to mention LGBTQI keywords on their websites. Given the increasing interest in LGBTQI education for OB-GYN trainees, program directors should consider providing training opportunities and including this content on their websites. [ABSTRACT FROM AUTHOR]

Background Methicillin-resistant Staphylococcus aureus (MRSA) has been a deadly pathogen in healthcare settings since the 1960s, but MRSA epidemiology changed since 1990 with new genetically distinct strain types circulating among previously healthy people outside healthcare settings. Community-associated (CA) MRSA strains primarily cause skin and soft tissue infections, but may also cause life-threatening invasive infections. First seen in Australia and the U.S., it is a growing problem around the world. The U.S. has had the most widespread CA-MRSA epidemic, with strain type USA300 causing the great majority of infections. Individuals with either asymptomatic colonization or infection may transmit CAMRSA to others, largely by skin-to-skin contact. Control measures have focused on hospital transmission. Limited public health education has focused on care for skin infections. Methods We developed a fine-grained agent-based model for Chicago to identify where to target interventions to reduce CA-MRSA transmission. An agent-based model allows us to represent heterogeneity in population behavior, locations and contact patterns that are highly relevant for CA-MRSA transmission and control. Drawing on nationally representative survey data, the model represents variation in sociodemographics, locations, behaviors, and physical contact patterns. Transmission probabilities are based on a comprehensive literature review. Results Over multiple 10-year runs with one-hour ticks, our model generates temporal and geographic trends in CA-MRSA incidence similar to Chicago from 2001 to 2010. On average, a majority of transmission events occurred in households, and colonized rather than infected agents were the source of the great majority (over 95%) of transmission events. The key findings are that infected people are not the primary source of spread. Rather, the far greater number of colonized individuals must be targeted to reduce transmission. Conclusions Our findings suggest that current paradigms in MRSA control in the United States cannot be very effective in reducing the incidence of CA-MRSA infections. Furthermore, the control measures that have focused on hospitals are unlikely to have much population-wide impact on CA-MRSA rates. New strategies need to be developed, as the incidence of CA-MRSA is likely to continue to grow around the world. [ABSTRACT FROM AUTHOR]

Canine hepatozoonosis is caused by Hepatozoon canis and Hepatozoon americanum, apicomplexan parasites transmitted to dogs by ingestion of infectious stages. Although the two agents are phylogenetically related, specific aspects, including characteristics of clinical disease and the natural history of the parasites themselves, differ between the two species. Until recently, H. canis infections had not been clearly documented in North America, and autochthonous infection with H. americanum has yet to be reported outside of the southern United States. However, recent reports demonstrate H. canis is present in areas of North America where its vector tick, Rhipicephalus sanguineus, has long been endemic, and that the range of H. americanum is likely expanding along with that of its vector tick, Amblyomma maculatum; co-infections with the two organisms have also been identified. Significant intraspecific variation has been reported in the 18S rRNA gene sequence of both Hepatozoon spp.-infecting dogs, suggesting that each species may represent a complex of related genogroups rather than well-defined species. Transmission of H. americanum to dogs via ingestion of cystozoites in muscle of infected vertebrates was recently demonstrated, supporting the concept of predation as a means of natural transmission. Although several exciting advances have occurred in recent years, much remains to be learned about patterns of infection and the nature of clinical disease caused by the agents of canine hepatozoonosis in North America. [ABSTRACT FROM AUTHOR]

Background: Vector-borne infections pose significant health risks to humans, domestic animals, and wildlife. Domestic dogs (Canis lupus familiaris) in the United States may be infected with and serve as sentinel hosts for several zoonotic vector-borne pathogens. In this study, we analyzed the geographical distribution, risk factors, and co-infections associated with infection with Ehrlichia spp., Anaplasma spp., Borrelia burgdorferi, and Dirofilaria immitis in shelter dogs in the Eastern United States. Methods: From 2016 to 2020, blood samples from 3750 shelter dogs from 19 states were examined with IDEXX SNAP® 4Dx® Plus tests to determine the seroprevalence of infection with tick-borne pathogens and infection with D. immitis. We assessed the impact of factors including age, sex, intact status, breed group, and location on infection using logistic regression. Results: The overall seroprevalence of D. immitis was 11.2% (n = 419/3750), the seroprevalence of Anaplasma spp. was 2.4% (n = 90/3750), the seroprevalence of Ehrlichia spp. was 8.0% (n = 299/3750), and the seroprevalence of B. burgdorferi was 8.9% (n = 332/3750). Regional variation in seroprevalence was noted: D. immitis (17.4%, n = 355/2036) and Ehrlichia spp. (10.7%, n = 217/2036) were highest in the Southeast while seroprevalence for B. burgdorferi (19.3%, n = 143/740) and Anaplasma spp. (5.7%, n = 42/740) were highest in the Northeast. Overall, 4.8% (n = 179/3750) of dogs had co-infections, the most common of which were D. immitis/Ehrlichia spp. (1.6%, n = 59/3750), B. burgdorferi/Anaplasma spp. (1.5%, n = 55/3750), and B. burgdorferi/Ehrlichia spp. (1.2%, n = 46/3750). Risk factors significantly influenced infection across the evaluated pathogens were location and breed group. All evaluated risk factors were significant for the seroprevalence of D. immitis antigens. Conclusions: Our results demonstrate a regionally variable risk of infection with vector-borne pathogens in shelter dogs throughout the Eastern United States, likely due to varying distributions of vectors. However, as many vectors are undergoing range expansions or other changes in distribution associated with climate and landscape change, continued vector-borne pathogen surveillance is important for maintaining reliable risk assessment. [ABSTRACT FROM AUTHOR]

Background: Dogs in the United States are hosts to a diverse range of vector-borne pathogens, several of which are important zoonoses. This paper describes factors deemed to be significantly related to the prevalence of antibodies to Ehrlichia spp. in domestic dogs, including climatic conditions, geographical factors, and societal factors. These factors are used in concert with a spatio-temporal model to construct an annual seroprevalence forecast. The proposed method of forecasting and an assessment of its fidelity are described. Methods: Approximately twelve million serological test results for canine exposure to Ehrlichia spp. were used in the development of a Bayesian approach to forecast canine infection. Data used were collected on the county level across the contiguous United States from routine veterinary diagnostic tests between 2011-2015. Maps depicting the spatial baseline Ehrlichia spp. prevalence were constructed using Kriging and head-banging smoothing methods. Data were statistically analyzed to identify factors related to antibody prevalence via a Bayesian spatio-temporal conditional autoregressive (CAR) model. Finally, a forecast of future Ehrlichia seroprevalence was constructed based on the proposed model using county-level data on five predictive factors identified at a workshop hosted by the Companion Animal Parasite Council and published in 2014: annual temperature, percentage forest coverage, percentage surface water coverage, population density and median household income. Data were statistically analyzed to identify factors related to disease prevalence via a Bayesian spatio-temporal model. The fitted model and factor extrapolations were then used to forecast the regional seroprevalence for 2016. Results: The correlation between the observed and model-estimated county-by-county Ehrlichia seroprevalence for the five-year period 2011-2015 is 0.842, demonstrating reasonable model accuracy. The weighted correlation (acknowledging unequal sample sizes) between 2015 observed and forecasted county-by-county Ehrlichia seroprevalence is 0.970, demonstrating that Ehrlichia seroprevalence can be forecasted accurately. Conclusions: The forecast presented herein can be an a priori alert to veterinarians regarding areas expected to see expansion of Ehrlichia beyond the accepted endemic range, or in some regions a dynamic change from historical average prevalence. Moreover, this forecast could potentially serve as a surveillance tool for human health and prove useful for forecasting other vector-borne diseases. [ABSTRACT FROM AUTHOR]

Background: In the USA, there are several Ehrlichia spp. of concern including Ehrlichia canis, Ehrlichia ewingii, Ehrlichia chaffeensis, Ehrlichia muris eauclarensis, and "Panola Mountain Ehrlichia". Of these, E. canis is considered the most clinically relevant for domestic dogs, with infection capable of causing acute, subclinical, and chronic stages of disease. Changes in climate, land use, habitats, and wildlife reservoir populations, and increasing contact between both human and dog populations with natural areas have resulted in the increased risk of vector-borne disease throughout the world., Methods: A Bayesian spatio-temporal binomial regression model was applied to serological test results collected from veterinarians throughout the contiguous USA between January 2013 and November 2019. The model was used to quantify both regional and local temporal trends of canine Ehrlichia spp. seroprevalence and identify areas that experienced significant increases in seroprevalence., Results: Regionally, increasing seroprevalence occurred within several states throughout the central and southeastern states, including Missouri, Arkansas, Mississippi, Alabama, Virginia, North Carolina, Georgia and Texas. The underlying local trends revealed increasing seroprevalence at a finer scale. Clusters of locally increasing seroprevalence were seen from the western Appalachian region into the southern Midwest, along the Atlantic coast in New England, parts of Florida, Illinois, Wisconsin and Minnesota, and in a couple areas of the Mountain region. Clusters of locally decreasing seroprevalence were seen throughout the USA including New York and the mid-Atlantic states, Texas, the Midwest, and California., Conclusions: Canine Ehrlichia spp. seroprevalence is increasing in both endemic and non-endemic areas of the USA. The findings from this study indicate that dogs across a wide area of the USA are at risk of exposure and these results should provide veterinarians and pet owners with the information they need to make informed decisions about prevention of tick exposure.

Background: Lyme disease (LD) is an infectious multi-system illness caused by the bacterial genus Borrelia and spread by bites of infected ticks. Although most patients are successfully treated by timely antibiotic therapy, it is broadly accepted that a sizeable number of patients experience treatment failure and continue to suffer long-term, debilitating symptoms, including pain, fatigue, cognitive dysfunction and other symptoms. This is known as post-treatment LD (PTLD), for which diagnosis is not standardized and treatment remains controversial. The prevalence and societal burden of PTLD is unknown.Methods: In an effort to help characterize the LD landscape, we estimated the number of PTLD cases in the US in 2016 and 2020 using Monte-Carlo simulation techniques, publically-available demographic datasets, uncertainty in the inputs and realistic assumptions about incidence and treatment failure rates.Results: Depending on the input assumptions, PTLD prevalence estimates for 2016 ranged from 69,011 persons (95% CI 51,796 to 89,312) to 1,523,869 (CI 1,268,634 to 1,809,416). Prevalence in 2020 is predicted to be higher than 2016, and may be as high as 1,944,189 (CI 1,619,988 to 2,304,147) cases.Conclusions: The cumulative prevalence of PLTD in the United States is estimated to be high and continues to increase. These findings will be of interest to epidemiologists and health economists studying disease burden in the US and elsewhere, and justify funding to study PTLD diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Background: Borrelia burgdorferi and Anaplasma phagocytophilum are tick-borne infections transmitted by Ixodes scapularis in the eastern USA; both agents cause disease in dogs and people. To characterize changes in seroprevalence over time, Cochran Armitage trend tests were used to evaluate percent positive test results for antibodies to B. burgdorferi and Anaplasma spp. in approximately 20 million canine tests from 2010-2017 in 25 states and 905 counties in the eastern USA., Results: A significant decreasing trend in seroprevalence to B. burgdorferi was evident in eight states along the mid-Atlantic coast from Virginia to New Hampshire, and in Wisconsin. In contrast, a continued increasing trend was evident in five northeastern and Midwestern states where Lyme borreliosis is endemic or emerging, as well as in three southern states where endemicity has not yet been widely established. Similarly, seroprevalence to Anaplasma spp. showed a significant, although smaller, decreasing trend in five states along the mid-Atlantic coast from Virginia to Connecticut and Rhode Island, as well as in Minnesota and Wisconsin in the Midwest; despite the fact that those trends were significant they were weak. However, a strong increasing trend was evident in Massachusetts and three states in northern New England as well as in Pennsylvania., Conclusions: As expected, seroprevalence continued to increase in regions where Lyme borreliosis and anaplasmosis are more newly endemic. However, the declining seroprevalence evident in other areas was not anticipated. Although the reasons for the decreasing trends are not clear, our finding may reflect shifting ecologic factors that have resulted in decreased infection risk or the combined positive influence of canine vaccination, tick control, and routine testing of dogs in regions where these infections have long been endemic. Analysis of trends in canine test results for tick-borne infections continues to be a valuable tool to understand relative geographical and temporal risk for these zoonotic agents.

Background: Forests in urban landscapes differ from their rural counterparts in ways that may alter vector-borne disease dynamics. In urban forest fragments, tick-borne pathogen prevalence is not well characterized; mitigating disease risk in densely-populated urban landscapes requires understanding ecological factors that affect pathogen prevalence. We trapped blacklegged tick (Ixodes scapularis) nymphs in urban forest fragments on the East Coast of the United States and used multiplex real-time PCR assays to quantify the prevalence of four zoonotic, tick-borne pathogens. We used Bayesian logistic regression and WAIC model selection to understand how vegetation, habitat, and landscape features of urban forests relate to the prevalence of B. burgdorferi (the causative agent of Lyme disease) among blacklegged ticks., Results: In the 258 nymphs tested, we detected Borrelia burgdorferi (11.2% of ticks), Borrelia miyamotoi (0.8%) and Anaplasma phagocytophilum (1.9%), but we did not find Babesia microti (0%). Ticks collected from forests invaded by non-native multiflora rose (Rosa multiflora) had greater B. burgdorferi infection rates (mean = 15.9%) than ticks collected from uninvaded forests (mean = 7.9%). Overall, B. burgdorferi prevalence among ticks was positively related to habitat features (e.g. coarse woody debris and total understory cover) favorable for competent reservoir host species., Conclusions: Understory structure provided by non-native, invasive shrubs appears to aggregate ticks and reservoir hosts, increasing opportunities for pathogen transmission. However, when we consider pathogen prevalence among nymphs in context with relative abundance of questing nymphs, invasive plants do not necessarily increase disease risk. Although pathogen prevalence is greater among ticks in invaded forests, the probability of encountering an infected tick remains greater in uninvaded forests characterized by thick litter layers, sparse understories, and relatively greater questing tick abundance in urban landscapes.

Background: Borrelia sp. is a causative pathogen of Lyme disease which has become a worldwide health concern. Non-toxic approaches especially directed toward latent persistent forms of this pathogen are desired. Lipids in the form of volatile and non-volatile oils, and fatty acids with proven anti-borreliae efficacy could become an additional support or an alternative for consideration in treatment approaches. Methods: In this study we investigated 47 lipids (30 volatile and non-volatile oils, and 17 fatty acids) of plant and animal origin against typical motile, knob/round-shaped persisters, and biofilm-like aggregates of Borrelia burgdorferi s.s. and Borrelia garinii, which are identified as pathogenic factors of Lyme disease in the USA and Europe, using direct microscopic counting and spectrofluorometric measurements. Results: Out of all examined lipids, 5 oils (Bay leaf oil, Birch oil, Cassia oil, Chamomile oil German, and Thyme oil) at or below 0.25%, and 3 fatty acids (13Z,16Z Docosadienoic acid, erucic acid, and petroselinic acid) at or below 0.75 mg/ml, showed bactericidal activity against typical motile spirochetes and knob/round-shaped persisters. Only Bay leaf oil and Cassia oil, including their major constituents, eugenol and cinnamaldehyde, showed to target biofilm-like aggregates of both tested Borrelia spp. at the same concentration, although with 20–30% eradication mark. Conclusion: Based on obtained results, volatile oils were more potent than non-volatile oils, and unsaturated fatty acids were more effective than saturated fatty acids. Among all tested oils, Bay leaf oil and Cassia oil, with their major components eugenol and cinnamaldehyde, seem to have the highest anti-borreliae efficacy. [ABSTRACT FROM AUTHOR]

Background: Babesiosis, a zoonotic parasitic infection transmitted by the Ixodes tick, has become an emerging health problem in humans that is attracting attention worldwide. Most cases of human babesiosis are reported in the United States and Europe. The disease is caused by the protozoa of the genus Babesia, which invade human erythrocytes and lyse them causing a febrile hemolytic anemia. The infection is usually asymptomatic or self-limited in the immunocompetent host, or follows a persistent, relapsing, and/or life threatening course with multi-organ failure, mainly in the splenectomized or immunosuppressed patients. Hematologic manifestations of the disease are common. They can range from mild anemia, to severe pancytopenia, splenic rupture, disseminated intravascular coagulopathy (DIC), or even hemophagocytic lymphohistiocytosis (HLH). Case presentation: A 70 year old immunocompetent female patient living in New York City presented with a persistent fever, night sweats, and fatigue of 5 days duration. Full evaluation showed a febrile hemolytic anemia along with neutropenia and thrombocytopenia. Blood smear revealed intraerythrocytic Babesia, which was confirmed by PCR. Bone marrow biopsy was remarkable for dyserythropoiesis, suggesting possible HLH, supported by other blood workup meeting HLH-2004 trial criteria. Conclusion: Human babesiosis is an increasing healthcare problem in the United States that is being diagnosed more often nowadays. We presented a case of HLH triggered by Babesia microti that was treated successfully. Also, we presented the hematologic manifestations of this disease along with their pathophysiologies. [ABSTRACT FROM AUTHOR]

Background: Dogs in the US are commonly infected with vector-borne pathogens, including heartworm and tick-borne disease agents. The geographic distribution of both arthropod vectors and the pathogens they transmit continues to expand., Methods: To describe the current geographic distribution and prevalence of antigen of Dirofilaria immitis and antibody to Borrelia burgdorferi, Ehrlichia spp., and Anaplasma spp. in dogs, we summarized over 144 million test results from 2013 to 2019, inclusive, by county, state, and region. Canine seroprevalence by state was compared to population-adjusted human reports of tick-borne diseases., Results: Results varied regionally, with D. immitis antigen and Ehrlichia spp. antibodies more frequently detected in the Southeast (2.6% and 5.2%, respectively) and antibody to B. burgdorferi and Anaplasma spp. most common in the Northeast (12.1% and 7.3%, respectively). Overall, percent positive test results to D. immitis decreased in the Southeast by 33.3% when compared to earlier summaries using the same strategy (from 3.9 to 2.6%). Geographic expansion of areas where dogs commonly test positive for Ehrlichia spp. was evident, likely because of a change in the test made in 2012 to allow detection of antibodies to E. ewingii concomitant with expansion of vector tick populations. Percent positive test results to Ehrlichia spp. increased in every region; this shift was particularly pronounced in the Southeast, where percent positive test results increased fourfold (from 1.3 to 5.2%). Continued geographic expansion of B. burgdorferi and A. phagocytophilum was apparent in the Northeast, Midwest, and Upper South, although canine seroprevalence of antibody to B. burgdorferi was much lower than prior surveys in many Lyme-endemic areas. Annual reports of human cases of Lyme disease, ehrlichiosis, and anaplasmosis were associated with percent positive canine results by state for the three tick-borne disease agents (R 2  = 0.812, 0.521, and 0.546, respectively). Within endemic areas, percent positive test results for all three tick-borne agents demonstrated evidence of geographic expansion., Conclusions: Large scale analysis of results from screening dogs in practice for evidence of vector-borne infections, including those with zoonotic importance, continues to be a valuable strategy for understanding geographic trends in infection risk over time.

Background: The main vector and reservoir host of Rickettsia felis, an emerging human pathogen causing flea-borne spotted fever, is the cat flea Ctenocephalides felis. While cats have not been found to be infected with the organism, significant percentages of dogs from Australia and Africa are infected, indicating that they may be important mammalian reservoirs. The objective of this study was to determine the presence of R. felis DNA in the blood of domestic dogs and cats in the USA., Methods: Three previously validated PCR assays for R. felis and DNA sequencing were performed on blood samples obtained from clinically ill domestic cats and dogs from 45 states (2008-2020) in the USA. The blood samples had been submitted for the diagnosis of various tick-borne diseases in dogs and feline infectious peritonitis virus, feline immunodeficiency virus, and Bartonella spp. in cats. Phylogenetic comparisons were performed on the gltA nucleotide sequences obtained in the study and those reported for R. felis and R. felis-like organisms., Results: Low copy numbers of R. felis DNA (around 100 copies/ml whole blood) were found in four cats (4/752, 0.53%) and three dogs (3/777, 0.39%). The very low levels of infection in clinically ill animals is consistent with R. felis being an unlikely cause of disease in naturally infected dogs and cats. The low copy numbers we found emphasize the requirement for very sensitive PCRs in prevalence studies., Conclusions: The low prevalence of naturally infected PCR-positive cats is further evidence that cats are unlikely to be important reservoirs of R. felis. Similarly, the low prevalence in dogs suggests they are not important reservoirs in the USA. Investigations should continue into the role other mammalian species may be playing in the epidemiology of R. felis infections.

Background: Lyme disease, caused by Borrelia burgdorferi, is the most common tick-borne infection in the United States. Although humans can be infected by at least 16 different strains of B. burgdorferi, the overwhelming majority of infections are due to only four strains. It was recently demonstrated that patients who are treated for early Lyme disease develop immunity to the specific strain of B. burgdorferi that caused their infection. The aim of this study is to estimate the reduction in cases of Lyme disease in the United States that may occur as a result of type specific immunity.Methods: The analysis was performed based on three analytical models that assessed the effects of type specific immunity. Observational data on the frequency with which different B. burgdorferi strains cause human infection in culture-confirmed patients with an initial episode of erythema migrans diagnosed between 1991 and 2005 in the Northeastern United States were used in the analyses.Results: Assuming a reinfection rate of 3 % and a total incidence of Lyme disease per year of 300,000, the estimated number of averted cases of Lyme disease per year ranges from 319 to 2378 depending on the duration of type specific immunity and the model used.Conclusion: Given the assumptions of the analyses, this analysis suggests that type specific immunity is likely to have public health significance in the United States. [ABSTRACT FROM AUTHOR]

Background Coxiella burnetii causes Q fever in humans and Coxiellosis in animals; symptoms range from general malaise to fever, pneumonia, endocarditis and death. Livestock are a significant source of human infection as they shed C. burnetii cells in birth tissues, milk, urine and feces. Although prevalence of C. burnetii is high, few Q fever cases are reported in the U.S. and we have a limited understanding of their connectedness due to difficulties in genotyping. Here, we develop canonical SNP genotyping assays to evaluate spatial and temporal relationships among C. burnetii environmental samples and compare them across studies. Given the genotypic diversity of historical collections, we hypothesized that the current enzootic of Coxiellosis is caused by multiple circulating genotypes. We collected A) 23 milk samples from a single bovine herd, B) 134 commercial bovine and caprine milk samples from across the U.S., and C) 400 bovine and caprine samples from six milk processing plants over three years. Results We detected C. burnetii DNA in 96% of samples with no variance over time. We genotyped 88.5% of positive samples; bovine milk contained only a single genotype (ST20) and caprine milk was dominated by a second type (mostly ST8). Conclusions The high prevalence and lack of genotypic diversity is consistent with a model of rapid spread and persistence. The segregation of genotypes between host species is indicative of species-specific adaptations or dissemination barriers and may offer insights into the relative lack of human cases and characterizing genotypes. [ABSTRACT FROM AUTHOR]

Background A study was conducted to evaluate and compare the effectiveness of two different spot-on topical flea products to control flea infestations on naturally infested dogs and cats in Tampa, FL USA. Methods Thirty-two dogs and 3 cats with natural flea infestations living in 18 homes were treated topically with a 19.53% w/w spot-on formulation of indoxacarb. Another thirty dogs and 2 cats living in 19 different homes were treated topically with either fipronil (9.8% w/w)/(s)-methoprene (8.89% w/w) or fipronil (9.8% w/w)/(s)-methoprene (11.8% w/w), respectively. All products were applied according to label directions by study investigators on day 0 and again between days 28 and 30. Flea populations on pets were assessed using visual area counts and premise flea infestations were assessed using intermittent-light flea traps on days 0, 7, 14, 21, 28-30, 40-45, and 54-60. Results A single application of the indoxacarb or fipronil (s)-methoprene formulations reduced flea populations on pets by 97.8% and 85.5%, respectively within 7 days. One month (28-30 days) after treatment the indoxacarb and fipronil (s)-methoprene formulations reduced onanimal flea burdens by 95.0% and 49.5%, respectively. Following two monthly applications of either the indoxacarb or fipronil (s)-methoprene formulations, pet flea burdens were reduced by 99.1% and 54.8%, respectively, by days 54-60. At the end of the two month study, 77.1% and 15.6% of the dogs and cats in the indoxacarb and fipronil (s)-methoprene treatment groups, respectively were flea free. Flea numbers in the indoor-premises were markedly reduced in both treatment groups by days 54-60, with 97.7% and 84.6% reductions in intermittent-light flea trap counts in the indoxacarb and fipronil (s)-methoprene treatment groups, respectively. Conclusions This in-home investigation conducted during the summer of 2013 in subtropical Tampa, FL, is the first published U.S field investigation of the indoxacarb topical formulation. The indoxacarb formulation was able to effectively control flea populations in heavily flea infested pets and homes. The efficacy achieved by the fipronil (s)-methoprene formulation against flea infestations on these pets was lower than in previous investigations using the same study design. [ABSTRACT FROM AUTHOR]