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Abstract Severe fever with thrombocytopenia syndrome (SFTS) is a fatal zoonosis caused by ticks in East Asia. As SFTS virus (SFTSV) is maintained between wildlife and ticks, seroepidemiological studies in wildlife are important to understand the behavior of SFTSV in the environment. Miyazaki Prefecture, Japan, is an SFTS-endemic area, and approximately 100 feral horses, called Misaki horses (Equus caballus), inhabit Cape Toi in Miyazaki Prefecture. While these animals are managed in a wild-like manner, their ages are ascertainable due to individual identification. In the present study, we conducted a seroepidemiological survey of SFTSV in Misaki horses between 2015 and 2023. This study aimed to understand SFTSV infection in horses and its transmission to wildlife. A total of 707 samples from 180 feral horses were used to determine the seroprevalence of SFTSV using enzyme-linked immunosorbent assay (ELISA). Neutralization testing was performed on 118 samples. In addition, SFTS viral RNA was detected in ticks from Cape Toi and feral horses. The overall seroprevalence between 2015 and 2023 was 78.5% (555/707). The lowest seroprevalence was 55% (44/80) in 2016 and the highest was 92% (76/83) in 2018. Seroprevalence was significantly affected by age, with 11% (8/71) in those less than one year of age and 96.7% (435/450) in those four years of age and older (p

We report the detection of Crimean-Congo hemorrhagic fever virus (CCHFV) in Corsica, France. We identified CCHFV African genotype I in ticks collected from cattle at 2 different sites in southeastern and central-western Corsica, indicating an established CCHFV circulation. Healthcare professionals and at-risk groups should be alerted to CCHFV circulation in Corsica.

Rickettsia occurs worldwide and rickettsiosis is recognized as an emerging infection in several parts of the world. Ticks are reservoir hosts for pathogenic Rickettsia species in humans and domestic animals. Most pathogenic Rickettsia species belong to the spotted Fever Group (SFG). This study aimed to identify and diagnose tick fauna and investigate the prevalence of Rickettsia spp. in ticks collected from domestic animals and dogs in the rural regions of Kerman Province, Southeast Iran. In this study, tick species (fauna) were identified and 2100 ticks (350 pooled samples) from two genera and species including Rhipicephalus linnaei (1128) and Hyalomma deteritum (972) were tested to detect Rickettsia genus using Real-time PCR. The presence of the Rickettsia genus was observed in 24.9% (95%CI 20.28–29.52) of the pooled samples. Sequencing and phylogenetic analyses revealed the presence of Rickettsia aeschlimannii (48.98%), Rickettsia conorii israelensis (28.57%), Rickettsia sibirica (20.41%), and Rickettsia helvetica (2.04%) in the positive samples. The results showed a significant association between county variables and the following variables: tick spp. (p < 0.001), Rickettsia genus infection in ticks (p < 0.001) and Rickettsia spp. (p < 0.001). In addition, there was a significant association between tick species and host animals (dogs and domestic animals) (p < 0.001), Rickettsia spp infection in ticks (p < 0.001), and Rickettsia spp. (p < 0.001). This study indicates a high prevalence of Rickettsia spp. (SFG) in ticks of domestic animals and dogs in rural areas of Kerman Province. The health system should be informed of the possibility of rickettsiosis and the circulating species of Rickettsia in these areas. [ABSTRACT FROM AUTHOR]

Background: Ticks are obligate hematophagous ectoparasites involved in transmitting viruses of public health importance. The objective of this work was to identify the Jingmen tick virus in hard ticks from the Colombian Caribbean, an arbovirus of importance for public health. Methods: Ticks were collected in rural areas of Córdoba and Cesar, Colombia. Taxonomic identification of ticks was carried out, and pools of 13 individuals were formed. RNA extraction was performed. Library preparation was performed with the MGIEasy kit, and next-generation sequencing (NGS) with MGI equipment. Bioinformatic analyses and taxonomic assignments were performed using the Galaxy platform, and phylogenetic analyses were done using IQ-TREE2. Results: A total of 766 ticks were collected, of which 87.33% (669/766) were Rhipicephalus microplus, 5.4% (42/766) Dermacentor nitens, 4.2% (32/766) Rhipicephalus linnaei, and 3.0% (23/766) Amblyomma dissimile. Complete and partial segments 1, 2, 3, and 4 of Jingmen tick virus (JMTV) were detected in the metatranscriptome of the species R. microplus, D. nitens, and A. dissimile. The JMTVs detected are phylogenetically related to JMTVs detected in Aedes albopictus in France, JMTVs detected in R. microplus in Trinidad and Tobago, JMTVs in R. microplus and A. variegatum in the French Antilles, and JMTVs detected in R. microplus in Colombia. Interestingly, our sequences clustered closely with JMTV detected in humans from Kosovo. Conclusions: JMTV was detected in R. microplus, D. nitens, and A. dissimile. JMTV could pose a risk to humans. Therefore, it is vital to establish epidemiological surveillance measures to better understand the possible role of JMTV in tropical diseases. [ABSTRACT FROM AUTHOR]

AbstractMulching leaves in place was studied for 4 years in Westchester County, New York State, USA. Soil testing showed an advantage in long-term mulch mowing for available water capacity and soil proteins with no detrimental effects on the health of the soil. There were no differences in the concentration of macro or micronutrients in the leaf and duff material between treatments or in the concentration of those nutrients being added or removed from the soil. Lawns that had been mulch mowed showed significantly higher pest and traffic tolerance than those where leaves had been removed. Drought stress tolerance remained the same on sites where mulch mowing had occurred, but decreased where leaves had been removed. Mowing practices accounted for less than one percent of the variation in tick numbers, indicating that other variables, not measured had a larger impact. The amount of fuel used for community pick-up of leaves was 4 and 33 times as much as mulch mowing for the two treatment groups. Based on the results of this 3-year study, mulch mowing of leaves provides some soil health benefits, many turf quality benefits, does not improve the habitat for pests and uses less fuel than community pick-up. This study showed that mulch mowing of leaves (i.e., leaving leaves on the lawn) does provide some benefits to soil health and turf quality, without having an adverse effect on nutrient load or tick habitat. [ABSTRACT FROM AUTHOR]

Background: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne zoonosis caused by the SFTS virus (SFTSV). Understanding the prevalence of SFTSV RNA in humans, vertebrate hosts and ticks is crucial for SFTS control. Methods: A systematic review and meta-analysis were conducted to determine the prevalence of SFTSV RNA in humans, vertebrate hosts and questing ticks. Nine electronic databases were searched for relevant publications, and data on SFTSV RNA prevalence were extracted. Pooled prevalence was estimated using a random effects model. Subgroup analysis and multivariable meta-regression were performed to investigate sources of heterogeneity. Results: The pooled prevalence of SFTSV RNA in humans was 5.59% (95% confidence interval [CI] 2.78–9.15%) in those in close contact (close contacts) with infected individuals (infected cases) and 0.05% (95% CI 0.00–0.65%) in healthy individuals in endemic areas. The SFTSV infection rates in artiodactyls (5.60%; 95% CI 2.95–8.96%) and carnivores (6.34%; 95% CI 3.27–10.23%) were higher than those in rodents (0.45%; 95% CI 0.00–1.50%). Other animals, such as rabbits, hedgehogs and birds, also played significant roles in SFTSV transmission. The genus Haemaphysalis was the primary transmission vector, with members of Ixodes, Dermacentor, and Amblyomma also identified as potential vectors. The highest pooled prevalence was observed in adult ticks (1.03%; 95% CI 0.35–1.96%), followed by nymphs (0.66%; 95% CI 0.11–1.50%) and larvae (0.01%; 95% CI 0.00–0.46%). The pooled prevalence in ticks collected from endemic areas (1.86%; 95% CI 0.86–3.14%) was higher than that in ticks collected in other regions (0.41%; 95% CI 0.12–0.81%). Conclusions: Latent SFTSV infections are present in healthy individuals residing in endemic areas, and close contacts with SFTS cases are at a significantly higher risk of infection. The type of animal is linked to infection rates in vertebrate hosts, while infection rates in ticks are associated with the developmental stage. Further research is needed to investigate the impact of various environmental factors on SFTSV prevalence in vertebrate hosts and ticks. [ABSTRACT FROM AUTHOR]

Tick paralysis is a potentially fatal condition caused by toxins produced and secreted by tick salivary glands. This survey presents clinical and epidemiological observations of tick paralysis cases in domestic animals in Cyprus. Local veterinarians report typical tick paralysis cases occurring in goats, sheep, dogs, and cats. The animals suffering from paralysis are free from other neurological diseases, have blood and biochemical parameters within normal ranges, and recover fast by simply removing the ticks found predominantly on the head and around the neck. Tick paralysis cases occur in a specific geographic area of Cyprus (Akamas peninsula), from September through March, but not every year. Instead, the phenomenon has 2 periodic cycles of occurrence, a 3- and a 7-yearcycle. The 2 cycles are differentiated by severity based on the number of affected animals and the resulting losses. As described for other tick-borne diseases, these cyclic patterns may be attributed to external factors, self-oscillations of the disease system, or the combined action of these mechanisms. Ticks collected from a recent paralysis case in a goat were morphologically and molecularly identified as Ixodes gibbosus. Efforts should be made to characterize the specific toxins involved in tick paralysis and to develop a vaccine, which could prevent significant losses of small ruminants, especially in free-ranging farming systems, a prevalent management approach observed in Cyprus and various regions worldwide. [ABSTRACT FROM AUTHOR]

Background: Powassan virus, a North American tick-borne flavivirus, can cause severe neuroinvasive disease in humans. While Ixodes scapularis are the primary vectors of Powassan virus lineage II (POWV II), also known as deer tick virus, recent laboratory vector competence studies showed that other genera of ticks can horizontally and vertically transmit POWV II. One such tick is the Haemaphysalis longicornis, an invasive species from East Asia that recently established populations in the eastern USA and already shares overlapping geographic range with native vector species such as I. scapularis. Reports of invasive H. longicornis feeding concurrently with native I. scapularis on multiple sampled hosts highlight the potential for interspecies co-feeding transmission of POWV II. Given the absence of a clearly defined vertebrate reservoir host for POWV II, it is possible that this virus is sustained in transmission foci via nonviremic transmission between ticks co-feeding on the same vertebrate host. The objective of this study was to evaluate whether uninfected H. longicornis co-feeding in close proximity to POWV II-infected I. scapularis can acquire POWV independent of host viremia. Methods: Using an in vivo tick transmission model, I. scapularis females infected with POWV II ("donors") were co-fed on mice with uninfected H. longicornis larvae and nymphs ("recipients"). The donor and recipient ticks were infested on mice in various sequences, and mouse infection status was monitored by temporal screening of blood for POWV II RNA via quantitative reverse transcription polymerase chain reaction (q-RT-PCR). Results: The prevalence of POWV II RNA was highest in recipient H. longicornis that fed on viremic mice. However, nonviremic mice were also able to support co-feeding transmission of POWV, as demonstrated by the detection of viral RNA in multiple H. longicornis dispersed across different mice. Detection of viral RNA at the skin site of tick feeding but not at distal skin sites indicates that a localized skin infection facilitates transmission of POWV between donor and recipient ticks co-feeding in close proximity. Conclusions: This is the first report examining transmission of POWV between co-feeding ticks. Against the backdrop of multiple unknowns related to POWV ecology, findings from this study provide insight on possible mechanisms by which POWV could be maintained in nature. [ABSTRACT FROM AUTHOR]

Background: Tacheng tick virus 2 (TcTV-2) is an emerging tick-borne virus belonging to the genus Uukuvirus in the family Phenuiviridae. Initially isolated in 2019 from a patient in Xinjiang Uygur Autonomous Region (XUAR), northwestern China, who developed fever and headache after a tick bite, TcTV-2 was concurrently molecularly detected in hard ticks across various countries, including China, Kazakhstan, Romania, and Turkey. This study conducted a retrospective epidemiological investigation of TcTV-2 infection. Methodology: In this retrospective cohort study, we collected samples from 47 tick-bitten patients, 984 herdsmen, 7 Asian badgers, 13 red foxes, and 168 Hyalomma asiaticum tick egg batches. Patients' samples were primarily analyzed by using high-throughput sequencing, targeting the V3-V4 region of the bacterial 16S rRNA gene and viral cDNA libraries. Typical tick-borne pathogens were further confirmed using RT-PCR and detected in Asian badgers, red foxes and Hy. asiaticum tick egg batches. We also conducted enzyme-linked immunosorbent assay (ELISA) to detected specific IgM and IgG antibodies against TcTV-2 in herdsmen. Phylogenetic analysis was performed to genetically characterize TcTV-2 detected in this study. Principal findings: TcTV-2 was detected in various samples, including blood, urine, and throat swabs from 12.77% (6/47) tick-bitten patients. It was found in blood samples of 14.29% (1/7) of wild badgers, 7.69% (1/13) of red foxes, and 13.69% (23/168) of Hy. asiaticum egg batches. Furthermore, ELISA results revealed that 9.55% (94/984) of the serum samples (34 from males and 60 from females) were tested positive for TcTV-2-specific IgG, while 2.95% (29/984, 7 males and 22 females) showed positivity for TcTV-2-specific IgM. Additionally, 1.02% (10/984, 4 males and 6 females) of the sera tested positive for both TcTV-2-specific IgM and IgG. Phylogenetic analysis indicated that the TcTV-2 strains detected in this study were genetically similar, regardless of their origin and host species. Conclusions: Clinical symptoms of TcTV-2 infection in patients are nonspecific, with common symptoms including headache, fever, asthenia, vomiting, myalgia, rash, and meningitis-like signs. TcTV-2 can be detected in blood, urine, and throat swab samples of infected patients. Among local herdsmen, 9.55% tested positive for TcTV-2-specific IgG and 2.95% for TcTV-2-specific IgM. Importantly, TcTV-2 can be transovarially transmitted in Hy. asiaticum ticks, and the Asian badgers and red foxes are potential reservoirs of TcTV-2. Author summary: Tacheng tick virus 2 was initially identified in China through a metagenomic analysis of ticks. A patient bitten by a tick was subsequently found to be infected with the virus, suggesting an association with human febrile disease. Subsequent detections of TcTV-2 in various tick species have been reported in Kazakhstan, Romania, Turkey, Poland, Ukraine, and Georgia. However, the infection dynamics of this emerging tick-borne virus in humans and animals remain unclear. In this study, we identified 6 additional patients infected with TcTV-2, presenting with nonspecific clinical symptoms such as fever, asthenia, vomiting, myalgia, rash, and signs resembling meningitis. TcTV-2 was detectable in blood, urine, and throat swabs. Moreover, 9.55% of local herdsmen tested positive for TcTV-2-specific IgG and 2.95% tested positive for specific IgM. We also identified Asian badgers and red foxes as potential animal reservoirs, highlighting that TcTV-2 can be transovarially transmitted in Hyalomma asiaticum ticks. These findings significantly contribute to our understanding of the infection and transmission dynamics of this emerging tick-borne virus. [ABSTRACT FROM AUTHOR]

Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne virus with a mortality rate of up to 30%. First identified in China in 2009, it was later reported in other Asian countries, including Thailand in 2020. SFTSV has been detected in several tick species, including Rhipicephalus sanguineus, known for infesting dogs. We conducted a seroprevalence study of SFTSV in Bangkok and Nong Khai, Thailand, by analyzing 1162 human samples collected between 2019 and 2023. The testing method relied on IgG detection using ELISA and confirmed though a virus seroneutralization test. The results indicated that out of the participants, 12 (1.1%) tested positive for anti-SFTSV IgG antibodies; however, none exhibited positive results in the seroneutralization assay. Additionally, molecular detection of SFTSV, Crimean-Congo hemorrhagic fever (CCHF), Coxiella spp., Bartonella spp., and Rickettsia spp. was performed on 433 Rh. sanguineus ticks collected from 49 dogs in 2023 in Chachoengsao Province, Thailand. No evidence of these pathogens was found in ticks. These findings highlight the importance of exploring viral cross-reactivity. Furthermore, it is important to conduct additional studies to isolate SFTSV from animals and ticks in order to identify the potential transmission routes contributing to human and animal infections in Thailand. [ABSTRACT FROM AUTHOR]

Amblyomma americanum, a known vector of multiple tick-borne pathogens, has expanded its geographic distribution across the United States in the past decades. Tick microbiomes may play a role shaping their host's life history and vectorial capacity. Bacterial communities associated with A. americanum may reflect, or enable, geographic expansion and studying the microbiota will improve understanding of tick-borne disease ecology. We examined the microbiota structure of 189 adult ticks collected in four regions encompassing their historical and current geographic distribution. Both geographic region of origin and sex were significant predictors of alpha diversity. As in other tick models, within-sample diversity was low and uneven given the presence of dominant endosymbionts. Beta diversity analyses revealed that bacterial profiles of ticks of both sexes collected in the West were significantly different from those of the Historic range. Biomarkers were identified for all regions except the historical range. In addition, Bray-Curtis dissimilarities overall increased with distance between sites. Relative quantification of ecological processes showed that, for females and males, respectively, drift and dispersal limitation were the primary drivers of community assembly. Collectively, our findings highlight how microbiota structural variance discriminates the western-expanded populations of A. americanum ticks from the Historical range. Spatial autocorrelation, and particularly the detection of non-selective ecological processes, are indicative of geographic isolation. We also found that prevalence of Ehrlichia chaffeensis, E. ewingii, and Anaplasma phagocytophilum ranged from 3.40–5.11% and did not significantly differ by region. Rickettsia rickettsii was absent from our samples. Our conclusions demonstrate the value of synergistic analysis of biogeographic and microbial ecology data in investigating range expansion in A. americanum and potentially other tick vectors as well. [ABSTRACT FROM AUTHOR]

Background: The Middle East and North Africa (MENA) offer optimal climatic conditions for tick reproduction and dispersal. Research on tick-borne pathogens in this region is scarce. Despite recent advances in the characterization and taxonomic explanation of various tick-borne illnesses affecting animals in Egypt, no comprehensive examination of TBP (tick-borne pathogen) statuses has been performed. Therefore, the present study aims to detect the prevalence of pathogens harbored by ticks in Egypt. Methodology/Principal findings: A four-year PCR-based study was conducted to detect a wide range of tick-borne pathogens (TBPs) harbored by three economically important tick species in Egypt. Approximately 86.7% (902/1,040) of the investigated Hyalomma dromedarii ticks from camels were found positive with Candidatus Anaplasma camelii (18.8%), Ehrlichia ruminantium (16.5%), Rickettsia africae (12.6%), Theileria annulata (11.9%), Mycoplasma arginini (9.9%), Borrelia burgdorferi (7.7%), Spiroplasma-like endosymbiont (4.0%), Hepatozoon canis (2.4%), Coxiella burnetii (1.6%) and Leishmania infantum (1.3%). Double co-infections were recorded in 3.0% (27/902) of Hy. dromedarii ticks, triple co-infections (simultaneous infection of the tick by three pathogen species) were found in 9.6% (87/902) of Hy. dromedarii ticks, whereas multiple co-infections (simultaneous infection of the tick by ≥ four pathogen species) comprised 12% (108/902). Out of 1,435 investigated Rhipicephalus rutilus ticks collected from dogs and sheep, 816 (56.9%) ticks harbored Babesia canis vogeli (17.1%), Rickettsia conorii (16.2%), Ehrlichia canis (15.4%), H. canis (13.6%), Bo. burgdorferi (9.7%), L. infantum (8.4%), C. burnetii (7.3%) and Trypanosoma evansi (6.6%) in dogs, and 242 (16.9%) ticks harbored Theileria lestoquardi (21.6%), Theileria ovis (20.0%) and Eh. ruminantium (0.3%) in sheep. Double, triple, and multiple co-infections represented 11% (90/816), 7.6% (62/816), and 10.3% (84/816), respectively in Rh. rutilus from dogs, whereas double and triple co-infections represented 30.2% (73/242) and 2.1% (5/242), respectively in Rh. rutilus from sheep. Approximately 92.5% (1,355/1,465) of Rhipicephalus annulatus ticks of cattle carried a burden of Anaplasma marginale (21.3%), Babesia bigemina (18.2%), Babesia bovis (14.0%), Borrelia theleri (12.8%), R. africae (12.4%), Th. annulata (8.7%), Bo. burgdorferi (2.7%), and Eh. ruminantium (2.5%). Double, triple, and multiple co-infections represented 1.8% (25/1,355), 11.5% (156/1,355), and 12.9% (175/1,355), respectively. The detected pathogens' sequences had 98.76–100% similarity to the available database with genetic divergence ranged between 0.0001 to 0.0009% to closest sequences from other African, Asian, and European countries. Phylogenetic analysis revealed close similarities between the detected pathogens and other isolates mostly from African and Asian countries. Conclusions/Significance: Continuous PCR-detection of pathogens transmitted by ticks is necessary to overcome the consequences of these infection to the hosts. More restrictions should be applied from the Egyptian authorities on animal importations to limit the emergence and re-emergence of tick-borne pathogens in the country. This is the first in-depth investigation of TBPs in Egypt. Author summary: Molecular monitoring of ticks for pathogen nucleic acids is informative when used in the surveillance of diseases transmitted by ticks. In the view of the limited information of genetic aspects of either ticks or their pathogen burdens in Egypt, it is crucial to give more attention into this direction to overcome the consequences might happen due to the caused diseases. We investigated three tick species (Rhipicephalus rutilus, Rh. annulatus, and Hyalomma dromedarii). These ticks are well-established in Egypt, infesting dogs, sheep, cattle, and camel among other hosts. The ticks were screened for the presence of different bacterial and protozoan pathogens using PCR technique for four years. The findings showed a prevalence of bacterial agents overall the ticks, followed by the protozoans. Surprisingly, the ticks showed different degrees of co-infections along with single infections. The data provided in this study should be used as a base in the construction of the "One health approach" that is being adopted by the country to protect the lives of both humans and their companion animals. [ABSTRACT FROM AUTHOR]

Simple Summary: In addition to infecting domestic dogs, Hepatozoon canis affects a large number of wild canids, such as foxes, jackals, and wolves, that can serve as reservoirs for this pathogen. In this study, we focused on the prevalence of H. canis, its genetic diversity, and its distribution in golden jackals on the territory of Serbia. At the same time, this is the first study in which a high genetic diversity of four sequence types (S4–S7) of H. canis has been found in golden jackals. In addition, a high prevalence rate was found, with 78.95% of animals testing positive for H. canis. Genetic analysis revealed variability at four positions, resulting in four different sequence types in golden jackals. Animals can become infected through the ingestion of infected ticks or by consuming infected prey, as well as transplacentally, from mother to offspring; what it could testify to 6/15 positive juvenile jackals. Additional research is crucial for elucidating transmission mechanisms, pinpointing potential sources of infection, and comprehending the ramifications of this pathogen for wild carnivores. Hepatozoon canis is a protozoan tick-borne parasite infecting domestic and wild canids, including foxes, wolves, and jackals. It is mainly found in dogs but has also been detected in several wild carnivores, including foxes, wolves, and jackals. Host transmission primarily occurs through the ingestion of infected ticks, typically Rhipicephalus sanguineus, with documented instances of transplacental transmission from infected females to cubs. In Serbia, the golden jackal is common throughout the country, and its population has increased in recent years. Previous research has documented the presence of several vector-borne pathogens in the jackal population in Serbia, so we conducted this study to determine the presence, prevalence, and genetic variability of H. canis. Over eleven years (2010–2020), 114 animal samples were collected from 23 localities in Serbia. A total of 90/114 (78.95%) jackals were positive for H. canis, and they came from 22 localities. Among 15 juveniles, almost half (6/15 (40%)) tested positive for H. canis. In addition to the high prevalence, high genetic variability of the pathogen was also found. According to the mutated positions, four sequence types (S4–S7) of H. canis were determined. Based on our earlier research on the grey wolf and on this study, it can be observed that various sequence types of H. canis circulate within wild canid populations in Serbia. The prevalence of H. canis infection in wild carnivores raises significant concerns for wildlife conservation and animal health. Infected animals may act as reservoirs for the disease, posing a potential risk to domestic animals by acting as a source of infection. [ABSTRACT FROM AUTHOR]

Serine proteinase inhibitors (serpins), identified from the hard tick Haemaphysalis longicornis of China, play significant roles in various animal physiological processes. In this study, we showed that H. longicornis serpins (Hlserpin‐a and Hlserpin‐b) were induced during blood‐feeding in nymph ticks and exhibited anticoagulation activity in vitro. Silencing Hlserpins through RNA interference (RNAi) significantly impaired tick feeding. Immunization of mice with recombinant Hlserpins or passive transfer of Hlserpin antiserum significantly curtails the efficacy of tick feeding. Concurrently, the transmission of the Langat virus (LGTV) from ticks to mice witnessed a substantial decrease when Hlserpins were silenced. Our findings suggest that inhibiting Hlserpins can hamper tick engorgement and pathogen transmission, indicating the potential of Hlserpins as a vaccine to counter tick‐borne diseases. [ABSTRACT FROM AUTHOR]

Anaplasma and Ehrlichia are tick-borne bacterial pathogens that cause anaplasmoses and ehrlichioses in humans and animals. In this study, we examined the prevalence of Anaplasma and Ehrlichia species in ticks and domesticated animals in Suizhou County, Hubei Province in the central China. We used PCR amplification and DNA sequencing of the 16S rRNA, groEL, and gltA genes to analyze. We collected 1900 ticks, including 1981 Haemaphysalis longicornis and 9 Rhipicephalus microplus, 159 blood samples of goats (n = 152), cattle (n = 4), and dogs (n = 3) from May to August of 2023. PCR products demonstrated that Anaplasma bovis, Anaplasma capra, and an Ehrlichia species were detected in the H. longicornis with the minimum infection rates (MIR) of 1.11%, 1.32%, and 0.05%, respectively; A. bovis, A. capra, and unnamed Anaplasma sp. were detected in goats with an infection rate of 26.31%, 1.31% and 1.97%, respectively. Anaplasma and Ehrlichia species were not detected from cattle, dogs and R. microplus ticks. The genetic differences in the groEL gene sequences of the Anaplasma in the current study were large, whereas the 16S rRNA and gltA gene sequences were less disparate. This study shows that ticks and goats in Suizhou County, Hubei Province carry multiple Anaplasma species and an Ehrlichia species, with relatively higher infection rate of A. bovis in goats. Our study indicates that multiple Anaplasma and Ehrlichia species exist in ticks and goats in the central China with potential to cause human infection. [ABSTRACT FROM AUTHOR]

Dugbe virus (DUGV) is a tick-borne arbovirus first isolated in Nigeria in 1964. It has been detected in many African countries using such diverse methods as serological tests, virus isolation, and molecular detection. In Senegal, reports of DUGV isolates mainly occurred in the 1970s and 1980s. Here, we report a contemporary detection of three novel DUGV isolates upon screening of a total of 2877 individual ticks regrouped into 844 pools. The three positive pools were identified as Amblyomma variegatum, the main known vector of DUGV, collected in the southern part of the country (Kolda region). Interestingly, phylogenetic analysis indicates that the newly sequenced isolates are globally related to the previously characterized isolates in West Africa, thus highlighting potentially endemic, unnoticed viral transmission. This study was also an opportunity to develop a rapid and affordable protocol for full-genome sequencing of DUGV using nanopore technology. The results suggest a relatively low mutation rate and relatively conservative evolution of DUGV isolates. [ABSTRACT FROM AUTHOR]

Powassan virus (POWV) is an emerging tick-borne encephalitic virus in Lyme disease-endemic sites in North America. Due to range expansion and local intensification of blacklegged tick vector (Ixodes scapularis) populations in the northeastern and upper midwestern U.S., human encephalitis cases are increasingly being reported. A better understanding of the transmission cycle between POWV and ticks is required in order to better predict and understand their public health burden. Recent phylogeographic analyses of POWV have identified geographical structuring, with well-defined northeastern and midwestern clades of the lineage II subtype. The extent that geographic and genetically defined sublineages differ in their ability to infect and be transmitted by blacklegged ticks is unclear. Accordingly, we determined whether there are strain-dependent differences in the transmission of POWV to ticks at multiple life stages. Five recent, low-passage POWV isolates were used to measure aspects of vector competence, using viremic and artificial infection methods. Infection rates in experimental ticks remained consistent between all five isolates tested, resulting in a 12–20% infection rate and some differences in viral load. We confirm that these differences are likely not due to differences in host viremia. Our results demonstrate that blacklegged ticks are susceptible to, and capable of transmitting, all tested strains and suggest that the tick–virus association is stable across diverse viral genotypes. [ABSTRACT FROM AUTHOR]

Hyalomma anatolicum is an economically important ixodid tick infesting cattle all around the globe as it is a vector for bovine tropical theilerosis. The present study was conducted for a period of one year in coastal Odisha and the prevalence of Hyalomma ticks were found to be 23.84%. There was a higher abundance of ticks during summer (29.56%), followed by monsoon (24.74%) and winter (17.22%). Tick population were highest during the month of May when temperature, relative humidity and rainfall recorded were 26.4–38.8 °C, 64% and 114.9 mm respectively. The correlation analysis of monthly tick burden with climatic factors revealed temperature to be the most dominant factor in abundance of ticks with highly significant correlation (p < 0.01) for minimum temperature (r = 0.899) and maximum temperature (r = 0.774). A moderate and low correlation was recorded for rainfall (r = 0.418) and relative humidity(r = 0.134) respectively. The investigation underlines the importance of various climatic factors on the abundance of the tick species. [ABSTRACT FROM AUTHOR]

The Asian leaf turtle (Cyclemys dentata) is a freshwater turtle species found in select Southeast Asian countries, including the Philippines. Our understanding of C. dentata's ecology in the Philippines is not yet fully understood and documented, and this is derived only from a few studies. In this paper, we present our single-event observation of an ectoparasite interaction between C. dentata and the Asian turtle tick (Amblyomma geoemydae) from Sitio Malbato, Barangay Bintuan Coron, Palawan. Our discovery serves as the second documented instance of this ectoparasite on C. dentata in the Philippines, hence extending its known distribution outside mainland Palawan. This finding contributes to the limited understanding of C. dentata's ecology and underscores the need for further field-based observations, which are crucial for their research and conservation. [ABSTRACT FROM AUTHOR]

Objective: To investigate the incidence and predisposing factors leading to the development of corneal ulcers and the loss of a palpebral reflex in hospitalised canine and feline patients with tick paralysis (TP). Animals studied: A total of 102 dogs and 100 cats retrospectively were assessed from previously hospitalised patients. Methods: A retrospective cohort study was performed on 102 different canine and 100 different feline patients who were hospitalised for TP from October 2020–January 2022. Patient data were collected, and logistic regression was conducted to determine factors affecting the palpebral reflex and the development of corneal ulcers. Results: Corneal ulcers occurred in 23/102 (22.5%) dogs during hospitalisation and were strongly associated with an incomplete palpebral reflex ipsilaterally during hospitalisation (P < 0.001), hospitalisation ≥3 days (P = 0.004), mechanical ventilation ≥3 days (P = 0.015) or a tick location cranial to C1 (P = 0.003). An incomplete palpebral reflex during hospitalisation was observed in 29/102 (28.4%) dogs and was significantly associated with decreasing patient weight (P = 0.018), increasing days hospitalised (P = 0.001), having a tick found cranial to C1 (P = 0.004), highest recorded GP grade (P = 0.01), highest recorded RP grade (P = 0.005), use of amoxycillin‐clavulanic acid during hospitalisation (P = 0.002) and use of piperacillin/tazobactam during hospitalisation (P = 0.003). There was a significant association between the loss of a complete palpebral reflex and mortality during hospitalisation in dogs (OR = 4.5, P = 0.029). Corneal ulcers occurred in 10/100 (10.0%) cats during hospitalisation, and was significantly more likely to occur to an eye if an incomplete palpebral reflex was observed ipsilaterally during hospitalisation (OR = 20.1, P < 0.0001) and with increasing patient age (P = 0.019). The absence of a complete palpebral reflex during hospitalisation was observed in 18/10 (18.0%) cats and was significantly associated with increasing days hospitalised (P = 0.034). There was no significant association between the loss of a complete palpebral reflex and mortality during hospitalisation in cats. Conclusions: The frequency of corneal ulcers and loss of palpebral reflexes were significant in dogs and cats hospitalised by TP, with many factors contributing to the risk of these developing. [ABSTRACT FROM AUTHOR]

This study documents the prevalence, mean intensity, mean abundance, aggregation, and seasonal variation of Amblyomma dissimile Koch in free-living snakes in the tropical humid climate of the Centro municipality of Tabasco, Mexico. A total of 19 snakes of seven species were captured manually during trail walks by trained personnel and carefully inspected for ticks. A morphological characterization identified the ticks as A. dissimile. Estimates indicated that 52.6% of the snakes had been parasitized by this tick. A total of 213 ticks were collected. The mean abundance was 11.2 (95% CI= 4-36), and the mean intensity was 21.3 (95% CI=8-57.1). Adult ticks were the most abundant, followed by nymphs and larvae. The most common parasitized body area was the first third of the snake's body, followed by the second, third, and finally, the head. Half of the inspected snakes were parasitized, and the ticks were found most frequently in the atlantooccipital joint area at the entrance to the stomach. There were high parasitic indices, abundances, and intensities, and Boa imperator Daudin was the most parasitized snake. More parasitized snakes were observed during the dry season. The study compiles relevant information about the presence of A. dissimile and their host snakes in Tabasco, Mexico. Resumen Este estudio documenta la prevalencia, intensidad media, abundancia media, agregación y variación estacional de Amblyomma dissimile Koch en serpientes de vida libre en el clima tropical húmedo del municipio Centro de Tabasco, México. Un total de 19 serpientes de siete especies fueron capturadas manualmente por personal capacitado durante recorridos en senderos. Cada serpiente fué cuidadosamente inspeccionada en busca de garrapatas. La caracterización morfológica permitió identificar a las garrapatas como A. dissimile. Las estimaciones indicaron que el 52.6% de las serpientes estaban parasitadas por esta garrapata. Se colectaron 213 garrapatas. La abundancia media fue 11.2 (IC 95%= 4-36), y la intensidad media fue 21.3 (IC 95%=8-57.1). Las garrapatas adultas fueron las más abundantes, seguidas de ninfas y larvas. El área corporal parasitada más común fue el primer tercio del cuerpo de la serpiente, seguido del segundo, tercero y finalmente la cabeza. La mitad de las serpientes inspeccionadas estaban parasitadas y las garrapatas se encontraron con mayor frecuencia de la zona de la articulación atlantooccipital a la entrada del estómago. Se detectaron índices altos para la abundancia e intensidad parasitaria, las serpientes de la especie Boa imperator Daudin fue la más parasitada. Se observó mayor cantidad de serpientes parasitadas durante la estación seca. El estudio recopila información relevante sobre la presencia de A. dissimile y sus serpientes hospedadoras en Tabasco, México. [ABSTRACT FROM AUTHOR]

We used entire mitochondrial (mt) genome sequences (14.5–15 kbp) to resolve the phylogeny of the four main lineages of the Haematobothrion ticks: Alloceraea, Archaeocroton, Bothriocroton and Haemaphysalis. In our phylogenetic trees, Alloceraea was the sister to Archaeocroton sphenodonti, a tick of an archetypal reptile, the tuatara, from New Zealand, to the exclusion of the rest of the species of Haemaphysalis. The mt genomes of all four of the Alloceraea species that have been sequenced so far had a substantial insert, 132–312 bp, between the tRNA‐Glu (E) gene and the nad1 gene in their mt genomes. This insert was not found in any of the other eight subgenera of Haemaphysalis. The mt genomes of 13 species of Haemaphysalis from NCBI GenBank were added to the most recent data set on Haemaphysalis and its close relatives to help resolve the phylogeny of Haemaphysalis, including five new subgenera of Haemaphysalis not previously considered by other authors: Allophysalis (structurally primitive), Aboimisalis (structurally primitive), Herpetobia (structurally intermediate), Ornithophysalis (structurally advanced) and Segalia (structurally advanced). We elevated Alloceraea Schulze, 1919 to the status of genus because Alloceraea Schulze, 1919 is phylogenetically distinct from the other subgenera of Haemaphysalis. Moreover, we propose that the subgenus Allophysalis is the sister to the rest of the Haemaphysalis (14 subgenera) and that the 'structurally primitive' subgenera Hoogstraal and Kim comprise early diverging lineages. Our matrices of the pairwise genetic difference (percent) of mt genomes and partial 16S rRNA sequences indicated that the mt genome sequence of Al. kitaokai (gb# OM368280) may not be Al. kitaokai Hoogstraal, 1969 but rather another species of Alloceraea. In a similar way, the mt genome sequence of H. (Herpetobia) nepalensis Hoogstraal, 1962 (gb# NC_064124) was only 2% genetically different to that of H. (Allophysalis) tibetensis Hoogstraal, 1965 (gb# OM368293): this indicates to us that they are the same species. Alloceraea cretacea may be better placed in a genus other than Alloceraea Schulze, 1919. Reptiles may have been the host to the most recent common ancestor of Archaeocroton and Alloceraea. [ABSTRACT FROM AUTHOR]

The recent recognition of a syndrome of tick‐acquired mammalian meat allergy has transformed the previously held view that mammalian meat is an uncommon allergen. The syndrome, mediated by IgE antibodies against the oligosaccharide galactose‐alpha‐1,3‐galactose (alpha‐gal), can also involve reactions to visceral organs, dairy, gelatin and other products, including medications sourced from non‐primate mammals. Thus, fittingly, this allergic disorder is now called the alpha‐gal syndrome (AGS). The syndrome is strikingly regional, reflecting the important role of tick bites in sensitization, and is more common in demographic groups at risk of tick exposure. Reactions in AGS are delayed, often by 2–6 h after ingestion of mammalian meat. In addition to classic allergic symptomatology such as urticaria and anaphylaxis, AGS is increasingly recognized as a cause of isolated gastrointestinal morbidity and alpha‐gal sensitization has also been linked with cardiovascular disease. The unusual link with tick bites may be explained by the fact that allergic cells and mediators are mobilized to the site of tick bites and play a role in resistance against ticks and tick‐borne infections. IgE directed to alpha‐gal is likely an incidental consequence of what is otherwise an adaptive immune strategy for host defense against endo‐ and ectoparasites, including ticks. [ABSTRACT FROM AUTHOR]

Simple Summary: Arthropods are a large and diverse group of animals, some of which are pests, while others transmit human and livestock diseases as they bite them to feed on blood. Chemical-based vector and pest control for decades has made many arthropods resistant to the chemicals used. So, there is a need to investigate other control agents, such as the biological, arthropod-killing fungus Metarhizium anisopliae, for the ability to infect and kill human and livestock disease-transmitting arthropods. In this study, we tested if the fungus M. anisopliae infects and kills mosquitoes, tsetse flies, and ticks. This was performed by finding out how long mosquitoes lived after being infected with fungus spores, as well as the amount of fungus spores suitable to lead to their death. The same optimal concentration of fungus that killed mosquitoes also successfully killed tsetse flies and ticks. We recommend that the fungus be formulated in a suitable concentration of 109 spores/mL and its ability to kill mosquitoes, tsetse flies, and ticks be confirmed in the field. This would lead to the development of a fungal formulation that can be sprayed on livestock such as cattle, for the exposure of multiple blood-feeding and disease-transmitting arthropods at the same time, to impact their survival. Arthropod vectors are responsible for a multitude of human and animal diseases affecting poor communities in sub-Saharan Africa. Their control still relies on chemical agents, despite growing evidence of insecticide resistance and environmental health concerns. Biorational agents, such as the entomopathogenic fungus Metarhizium anisopliae, might be an alternative for vector control. Recently, the M. anisopliae isolate ICIPE 7 has been developed into a commercial product in Kenya for control of ticks on cattle. We were interested in assessing the potential of controlling not only ticks but also disease-transmitting mosquitoes and tsetse flies using cattle as blood hosts, with the aim of developing a product for integrated vector management. Laboratory bioassays were carried out with M. anisopliae, isolate ICIPE 7 and isolate ICIPE 30, to compare efficacy against laboratory-reared Anopheles arabiensis. ICIPE 7 was further tested against wild Glossina fuscipes and Rhipicephalus spp. Dose–response tests were implemented, period of mosquito exposure was evaluated for effects on time to death, and the number of spores attached to exposed vectors was assessed. Exposure to 109 spores/mL of ICIPE 7 for 10 min resulted in a similar mortality of An. arabiensis as exposure to ICIPE 30, albeit at a slower rate (12 vs. 8 days). The same ICIPE 7 concentration also resulted in mortalities of tsetse flies (LT50: 16 days), tick nymphs (LT50: 11 days), and adult ticks (LT50: 20 days). Mosquito mortality was dose-dependent, with decreasing LT50 of 8 days at a concentration of 106 spores/mL to 6 days at 1010 spores/mL. Exposure period did not modulate the outcome, 1 min of exposure still resulted in mortality, and spore attachment to vectors was dose-dependent. The laboratory bioassays confirmed that ICIPE 7 has the potential to infect and cause mortality to the three exposed arthropods, though at slower rate, thus requiring further validation under field conditions. [ABSTRACT FROM AUTHOR]

Simple Summary: In the southeastern United States of America, shifts in the environment such as climate change and host availability are pushing tick populations to spread into new areas. It is hypothesized that, as they migrate, tick populations have developed a behavior known as incomplete feeding. With this, ticks feed on more than one host at each life stage, increasing the chance of pathogen transmission. In South Carolina, we found evidence of ticks displaying this behavior. We collected engorged female ticks from stray dogs at animal shelters across the state in 2022. Testing showed that about a third of these ticks had fed on humans. The patterns varied depending on the tick species, where they were found, and the time of collection. This pilot study reflects the growing trend of tick-borne diseases in the southeastern USA. It is crucial to dig deeper into how factors like the season, location, and species are linked to incomplete feeding behavior in South Carolina's tick populations. Dynamic environmental conditions, such as climate change and host availability, have greatly influenced the expansion of medically relevant tick vectors into new regions throughout the southeastern United States of America. As tick populations migrate into new areas, it has been suggested they can exhibit a phenomenon known as incomplete feeding. With this phenomenon, tick vectors feed on more than one host at each life stage, thus increasing the likelihood of pathogen transmission. Although this behavior is not well understood, it presents an important threat to human health. Here we present evidence of incomplete feeding behaviors in multiple tick species in South Carolina. Engorged, blood-fed female ticks were collected from feral dogs at animal shelters across South Carolina in 2022. All ticks were tested for human blood meals using rapid stain identification blood tests. Approximately one third (33.78%) of all ticks tested positive for a human blood meal, with various patterns seen across species, geographic location, and collection month. The results of this pilot study follow the current national trend of increasing rates of tick-borne disease incidence in the southeastern United States of America and warrant further investigation into the relationship between seasonality, geographic distribution, species, and incomplete feeding among tick populations in South Carolina. [ABSTRACT FROM AUTHOR]

Simple Summary: Haemaphysalis longicornis is a predominant tick species in East Asia and infests humans, cattle and wildlife. It is also a common vector for pathogen transmission. The microbial community in tick midguts not only affects the transmission of tick-borne pathogens but also indirectly affects the development, metabolism, reproduction, and other physiology of ticks. There have been rare reports on the effects of different types of hosts on the microbial composition of tick midguts. Here, we conducted a midgut microbiome of H. longicornis collected from tiger and deer by high-throughput sequencing and showed that the relative abundance of each bacterium varied greatly at different classification levels. Haemaphysalis longicornis is a common tick species that carries several pathogens. There are few reports on the influence of different hosts on the structure of midgut microflora in H. longicornis. In this study, midgut contents of fully engorged female H. longicornis were collected from the surface of tiger (Panthera tigris) and deer (Dama dama). The bacterial genomic DNA of each sample was extracted, and the V3–V4 regions of the bacterial 16S rRNA were sequenced using the Illumina NovaSeq sequencing. The diversity of the bacterial community of the fully engorged female H. longicornis on the surface of tiger was higher than that of deer. In total, 8 phyla and 73 genera of bacteria annotations were detected in the two groups. At the phylum level, the bacterial phyla common to the two groups were Proteobacteria, Firmicutes, and Actinobacteriota. At the genus level, there were 20 common bacterial genera, among which the relative abundances of Coxiella, Morganella, Diplorickettsia, and Acinetobacter were high. The Morganella species was further identified to be Morganella morganii. The alpha diversity index indicated that the bacterial diversity of the tiger group was higher than that of the deer group. Bacteroidota, Patescibacteria, Desulfobacterota, Verrucomicrobiota, and Cyanobacteria were solely detected in the tiger group. A total of 52 bacterial genera were unique in the tiger group, while one bacterial genus was unique in the deer group. This study indicates that there are differences in the structure of the gut bacteria of the same tick species among different hosts. Further culture-based methods are needed to provide a more comprehensive understanding of the tick microbiota parasitizing different hosts. [ABSTRACT FROM AUTHOR]

Tick Hill gold deposit is a unique gold mineralisation style in the Mary Kathleen Fold Belt in the Mount Isa Inlier. The gold at Tick Hill is generally pure without silver and was formed during two discrete metamorphic-deformation events (D1 and D3). Early gold was observed as inclusions or coarse grains hosted within D1 peak-metamorphic diopside, scapolite and hornblende from the garnet–biotite–hornblende (tschemakite)–plagioclase (andesine)–quartz assemblage. Late gold is closely associated with bismuth selenide, chlorite, albite, sericite and K-feldspar, and formed during D3. The syn-D1 garnet–plagioclase–hornblende–quartz–biotite assemblage was used to constrain the pressure and temperature (P–T) conditions of metamorphism and mineralisation using the garnet–plagioclase–hornblende–quartz barometer and the hornblende–plagioclase, garnet–biotite and garnet–hornblende thermometers. The results show that peak metamorphism at Tick Hill reached P–T conditions of 6.0–7.6 kbar and 720–760 °C. These P–T conditions together with gneissic and migmatisation textures recorded in different rock types at the Tick Hill area indicate that the peak metamorphism preserved in the area occurred at the amphibolite–granulite facies, compared with the amphibolite facies at the southern Mary Kathleen and Eastern Fold Belt. The D3 chlorite, which formed during stage 2 to stage 4 mineralisation events, displays a wide range of compositions reflecting a gradual retrograde temperature change from ∼380 °C to ∼130 °C. The pressures during D3 could not be reliably determined, but the presence of various Bi-selenides suggests that towards the waning stages of D3, the rocks may have been exhumed to a pressure less than 1 kbar. The 1790–1770 Ma D1 peak metamorphism at Tick Hill reached 6–7.6 kbar and 720–760 °C. The 1525–1520 Ma D3 hydrothermal mineralisation at Tick Hill Deposit occurred at temperatures between ∼380 °C and ∼130 °C. The main D3 gold accumulation episodes at Tick Hill occurred at temperatures ranging from ∼380 to 160 °C. [ABSTRACT FROM AUTHOR]

Canine vector-borne diseases (CVBDs) disproportionally affect dogs in the tropics, and some of them are of zoonotic concern. Control strategies should consider several factors, such as pathogen transmission times, vector seasonality, and individual risk factors. Combinations of repellents and fast-killing parasiticides are the first-line strategies for the prevention and control of CVBDs. Further research on transmission-blocking vaccines is needed for planning integrated control approaches against CVBDs. The prevention of canine vector-borne diseases (CVBDs) is pivotal for the health and welfare of dogs as well as for reducing their zoonotic risk to humans. Scientific knowledge gained in recent years contributed to the development of new strategies for the control of these diseases in different social and cultural contexts. Here, we discuss recent advances in the prevention of vector-borne pathogens (VBPs) affecting dogs with a focus on those of zoonotic relevance. [ABSTRACT FROM AUTHOR]

Ticks are notorious blood‐sucking ectoparasites that affect both humans and animals. They serve as a unique vector of various deadly diseases. Here, we have shown the roles of the receptor for advanced glycation end products (RAGE) during repeated infestations by the tick Haemaphysalis longicornis using RAGE−/− mice. In primary infestation, a large blood pool developed, which was flooded with numerous RBCs, especially during the rapid feeding phase of the tick both in wild‐type (wt) and RAGE−/− mice. Very few inflammatory cells were detected around the zones of haemorrhage in the primary infestations. However, the number of inflammatory cells gradually increased in the subsequent tick infestations, and during the third infestations, the number of inflammatory cells reached to the highest level (350.3 ± 16.8 cells/focus). The site of attachment was totally occupied by the inflammatory cells in wt mice, whereas very few cells were detected at the ticks' biting sites in RAGE−/− mice. RAGE was highly expressed during the third infestation in wt mice. In the third infestation, infiltration of CD44+ lymphocytes, eosinophils and expression of S100A8 and S100B significantly increased at the biting sites of ticks in wt, but not in RAGE−/− mice. In addition, peripheral eosinophil counts significantly increased in wt but not in RAGE−/− mice. Taken together, our study revealed that RAGE‐mediated inflammation and eosinophils played crucial roles in the tick‐induced inflammatory reactions. [ABSTRACT FROM AUTHOR]

Emerging and re‐emerging pathogens often stem from zoonotic origins, cycling between humans and animals, and are frequently vectored and maintained by hematophagous arthropod vectors. The efficiency by which these disease agents are successfully transmitted between vertebrate hosts is influenced by many factors, including the host on which a vector feeds. The Lyme disease bacterium Borrelia burgdorferi sensu lato has adapted to survive in complex host environments, vectored by Ixodes ticks, and maintained in multiple vertebrate hosts. The versatility of Lyme borreliae in disparate host milieus is a compelling platform to investigate mechanisms dictating pathogen transmission through complex networks of vertebrates and ticks. Squamata, one of the most diverse clade of extant reptiles, is comprised primarily of lizards, many of which are readily fed upon by Ixodes ticks. Yet, lizards are one of the least studied taxa at risk of contributing to the transmission and life cycle maintenance of Lyme borreliae. In this review, we summarize the current evidence, spanning from field surveillance to laboratory infection studies, supporting their contributions to Lyme borreliae circulation. We also summarize the current understanding of divergent lizard immune responses that may explain the underlying molecular mechanisms to confer Lyme spirochete survival in vertebrate hosts. This review offers a critical perspective on potential enzootic cycles existing between lizard‐tick‐Borrelia interactions and highlights the importance of an eco‐immunology lens for zoonotic pathogen transmission studies. [ABSTRACT FROM AUTHOR]

Hard ticks of the genus Ixodes are one of the most diverse groups in the Neotropical region, but some species are known only from historical records. In Colombia and Venezuela, Ixodes montoyanus is known from records obtained more than 50 years ago. In this study, we performed morphological and molecular evaluations of immature and adult stages of I. montoyanus collected from Pudu (Pudella) mephistophiles, in the municipality of Puracé, Cauca, in the Andean region of Colombia. The results include the first morphological evaluations of larvae, nymphs, females and males of I. montoyanus, confirming each of these stages with their respective sequences of a fragment of the mitochondrial 16S rRNA gene, and nymphs and females with a fragment of the mitochondrial cox1 gene. These results represent the first molecular information of I. montoyanus from Colombia, allowing differentiation of this species from others within Ixodes distributed in the country. The data generated consolidate valuable information for the genus Ixodes, which plays an important role in pathogen transmission. The information is also key to addressing the controversy regarding the identification, validity and distribution of various species within the genus. [ABSTRACT FROM AUTHOR]

The livelihoods of local farmers and game ranchers in Africa – and the communities these businesses support – are threatened by tick-borne diseases that kill and weaken livestock. Understanding the local ecology of ticks may inform cost-effective and sustainable techniques for controlling tick populations. Our objective was to describe differences in tick abundance, species richness, and community structure in three different habitats from June-July 2022 on a game reserve in the Limpopo Province of South Africa. Ticks were sampled using the drag method, in 54 30 m × 5 m transects evenly distributed across bushveld, long grass, and short grass habitats. Total tick abundance and species richness were significantly greater in long grass than in bushveld and short grass. Although there were no significant differences among the habitats in Simpson's diversity, the composition of the communities did vary significantly, with the relative abundances of Rhipicephalus appendiculatus and R. evertsi evertsi peaking in long grass, Amblyomma hebraeum peaking in bushveld, and R. decoloratus peaking in short grass. Differences in habitat suitability for ticks and habitat use by ungulate hosts may explain the significant effect of habitat on tick abundance, species richness, and community structure. [ABSTRACT FROM AUTHOR]

Of the 44 species within the genus Dermacentor (Acari: Ixodidae) worldwide, nine are found in the Neotropics and four are endemic to this region. In Colombia, located in the northwestern corner of South America, there are two species of the genus: Dermacentor imitans restricted to the trans-Andean Pacific region, and Dermacentor nitens widely distributed in the country. Elsewhere, D. nitens is found in both the Nearctic and Neotropics, from southern USA to northern Argentina. In the Neotropics, D. nitens is widely distributed including records in Caribbean islands. Molecular analyses of D. nitens collected in the Amazon region of Colombia have shown genetic differences with specimens from other localities of the country, although morphological differences have not been explored. We performed morphological and molecular comparisons of individuals from two natural regions of Colombia: the Orinoquia, and the Amazon. The morphological and morphometric results show that females and males are grouped in two morphotypes: morphotype I from the Orinoquia region, and morphotype II from Leticia in the Amazon region. The molecular analyses supported the morphological results and showed the formation of two well-differentiated sister clades within D. nitens, with divergences between both morphotypes of 3–4% and 5–6% for the 16S rRNA and COI genes, respectively. Species delimitation analyzes and the Poisson Tree Processes model tentatively suggest the presence of two species within the sequences associated with D. nitens in Colombia. The first represented by the sequences from the Orinoquia region evaluated here, together with sequences from other regions of Colombia and other Neotropical countries such as Brazil, Panama, and French Guiana. The second is represented by the sequences of individuals from Leticia, in the Amazon region of Colombia. The results highlight that D. nitens might represent a species complex, but further sampling, experimental crosses, and studies at the level of complete genomes should be performed to obtain additional evidence for species recognition. [ABSTRACT FROM AUTHOR]

Amblyomma multipunctum is a poorly known Neotropical tick (Acari, Ixodidae) described in 1899. It has been found associated with large mammals such as tapirs (Tapirus), and the Andean bear (Tremarctos ornatus). Males, females and nymphs have been described; however, the larvae of the species remain unknown. Valid records for A. multipunctum are few and limited to three countries in northwestern South America: Colombia, Ecuador, and Venezuela. In the present work, two partially engorged nymphs of A. multipunctum parasitizing the northern pudu, Pudu (Pudella) mephistophiles, were collected near to the Puracé National Natural Park, Department of Cauca, Colombia. Ticks were identified by morphology, with diagnostic characters such as scutum with multiple punctuations, two separate spurs in coxa I (the external being longer than the internal), a small triangular spur in coxae II–IV, spiracular plate triangular with rounded angles and a vestigial prolongation in article I of the palps. In addition, the taxonomical identity was validated using molecular evidence by PCR amplification of a fragment of the 16S rDNA gene, showing an identity percentage of 100% comparing with sequences in GenBank for A. multipunctum. This study reports the first association of A. multipunctum with P. mephistophiles, the extension of geographical distribution in Colombia, extending its elevational range by 644 m in the country, and contributing to the knowledge of the intraspecific variation of the tick nymph. [ABSTRACT FROM AUTHOR]

Background:Ehrlichia canis has been the main hemopathogen affecting domestic dogs in Brazil. Even though tick-infested dogs may lead to household infestation and predispose human exposure and public health concern, no comprehensive study has surveyed humans, dogs, and environmental ticks altogether. Materials and Methods: Accordingly, the present study aimed to assess tick-infested households, identify tick species, perform serological (immunofluorescence assay) and molecular (PCR and q-PCR) detection of Ehrlichia in ticks, in the eighth biggest metropolitan area of Brazil. Results: Between 2007 and 2020, 233/5973 (3.9%) out of all complaints were from tick-infested households of 200 different addresses. Overall, 370/552 (67.0%) ticks were collected and identified as adult and 182/552 (33.0%) as immature forms of Rhipicephalus sanguineus s.l. complex; a single tick from one owner, a female tick of Amblyomma sculptum; and 395 ticks from dogs, 319/395 (80.8%) adult and 72/395 (18.2%) immature forms of Rhipicephalus spp., and 4/395 (1.01%) female Amblyomma aureolatum. Overall, 2/135 (1.5%) owners and 13/136 (9.6%) dogs were seropositive for E. canis. The DNA of Anaplasmataceae family was molecularly detected in 16/50 (32.0%) R. sanguineus s.l. As expected, the number of monthly tick infestation complaints were directly associated, and mean (p = 0.01), maximum (p = 0.011), and minimum (p = 0.008) temperature were statistically significant and had a low positive correlation (0.24, 0.23, and 0.24, respectively). In addition, complaints were highly associated to all socioeconomic variables (p < 0.001), with the exception of the presence of vacant lots. Conclusions: Despite low samplings and human negative results, areas with low-income with adequate temperature and urban agglomerations have been shown to be associated risks for tick infestations, predisposing tick-borne diseases. In conclusion, monitoring should always be conducted in such areas, including One Health approach with serosurvey of owners and dogs, along with identification and molecular screening of ticks. [ABSTRACT FROM AUTHOR]

Crimean–Congo hemorrhagic fever (CCHF) is a zoonotic tick-borne disease, caused by an arbovirus of the genus Orthonairovirus and the family Nairoviridae. Crimean–Congo hemorrhagic fever virus (CCHFV) is widespread in several regions of the world. While the virus is not pathogenic to all susceptible livestock and wild mammals, it can lead to severe hemorrhagic fever in humans. In this review, we compiled published data on CCHFV infections in humans, animals, and ticks in Tunisia. Based on that, we discussed the epidemiology and the distribution patterns of CCHFV infections highlighting the risk factors for this virus in the country. CCHF infection prevalence in humans was estimated to 2.76% (5/181) and 5% (2/38) in Tunisian febrile patients and Tunisian slaughterhouse workers, respectively. Concurrently, seroprevalence in domestic ungulates (sheep, goats, cattle, and dromedaries) ranged from zero to 89.7%, and only one Hyalomma impeltatum tick specimen collected from dromedaries in southern Tunisian was positive for CCHFV by reverse transcriptase–polymerase chain reaction (0.6%; 1/165). As Tunisian studies on CCHFV are geographically scattered and limited due to very small sample sizes, further studies are needed to improve the knowledge on the epidemiology of CCHF in Tunisia. [ABSTRACT FROM AUTHOR]

This article examines the misidentification of arthropods as ticks in community science programs, specifically focusing on the eTick platform in Canada. The study analyzes non-target taxa submissions from 2019 to 2023 and identifies commonly mistaken arthropods such as spider beetles, Japanese beetles, and weevils. The article suggests that certain characteristics of these arthropods, such as their appearance and habitat, contribute to the misidentification. The study emphasizes the need for better outreach tools and education to help the public differentiate between ticks and other arthropods, and highlights the importance of regional context and language in community science programs. Ultimately, the article advocates for a multi-faceted approach to combat entomophobia and promote a harmonious coexistence between humans and arthropods. [Extracted from the article]

In the United States, there has been a steady increase in diagnosed cases of tick-borne diseases in people, most notably Lyme disease. The pathogen that causes Lyme disease, Borrelia burgdorferi, is transmitted by the blacklegged tick (Ixodes scapularis). Several small mammals are considered key reservoirs of this pathogen and are frequently-used hosts by blacklegged ticks. However, limited studies have evaluated between-species host use by ticks. This study compared I. scapularis burdens and tick-associated pathogen presence in wild-caught Clethrionomys gapperi (southern red-backed voles) and Peromyscus spp. (white-footed mice) in forested areas where the habitat of both species overlapped. Rodent trapping data collected over two summers showed a significant difference in the average tick burden between species. Adult Peromyscus spp. had an overall mean of 4.03 ticks per capture, while adult C. gapperi had a mean of 0.47 ticks per capture. There was a significant association between B. burgdorferi infection and host species with more Peromyscus spp. positive samples than C. gapperi (65.8% and 10.2%, respectively). This work confirms significant differences in tick-host use and pathogen presence between sympatric rodent species. It is critical to understand tick-host interactions and tick distributions to develop effective and efficient tick control methods. [ABSTRACT FROM AUTHOR]

Background: South Downs National Park (SDNP) is UK's most visited National Park, and a focus of tick-borne Lyme disease. The first presumed UK autochthonous cases of tick-borne encephalitis and babesiosis were recorded in 2019–20. SDNP aims to conserve wildlife and encourage recreation, so interventions are needed that reduce hazard without negatively affecting ecosystem health. To be successful these require knowledge of site hazards. Methods: British Deer Society members submitted ticks removed from deer. Key potential intervention sites were selected and six 50 m2 transects drag-sampled per site (mostly twice yearly for 2 years). Ticks were identified in-lab (sex, life stage, species), hazard measured as tick presence, density of ticks (all life stages, DOT), and density of nymphs (DON). Sites and habitat types were analysed for association with hazard. Distribution was mapped by combining our results with records from five other sources. Results: A total of 87 Ixodes ricinus (all but one adults, 82% F) were removed from 14 deer (10 Dama dama; three Capreolus capreolus; one not recorded; tick burden, 1–35) at 12 locations (commonly woodland). Five key potential intervention sites were identified and drag-sampled 2015–16, collecting 623 ticks (238 on-transects): 53.8% nymphs, 42.5% larvae, 3.7% adults (13 M, 10 F). Ticks were present on-transects at all sites: I. ricinus at three (The Mens (TM); Queen Elizabeth Country Park (QECP); Cowdray Estate (CE)), Haemaphysalis punctata at two (Seven Sisters Country Park (SSCP); Ditchling Beacon Nature Reserve (DBNR)). TM had the highest DOT at 30/300 m2 (DON = 30/300 m2), followed by QECP 22/300 m2 (12/300 m2), CE 8/300 m2 (6/300 m2), and SSCP 1/300 m2 (1/300 m2). For I. ricinus, nymphs predominated in spring, larvae in the second half of summer and early autumn. The overall ranking of site hazard held for DON and DOT from both seasonal sampling periods. DBNR was sampled 2016 only (one adult H. punctata collected). Woodland had significantly greater hazard than downland, but ticks were present at all downland sites. I. ricinus has been identified in 33/37 of SDNPs 10 km2 grid squares, Ixodes hexagonus 10/37, H. punctata 7/37, Dermacentor reticulatus 1/37. Conclusions: Mapping shows tick hazard broadly distributed across SDNP. I. ricinus was most common, but H. punctata's seeming range expansion is concerning. Recommendations: management of small heavily visited high hazard plots (QECP); post-visit precaution signage (all sites); repellent impregnated clothing for deerstalkers; flock trials to control H. punctata (SSCP, DBNR). Further research at TM may contribute to knowledge on ecological dynamics underlying infection density and predator re-introduction/protection as public health interventions. Ecological research on H. punctata would aid control. SDNP Authority is ideally placed to link and champion policies to reduce hazard, whilst avoiding or reducing conflict between public health and ecosystem health. [ABSTRACT FROM AUTHOR]

Cattle health in wildlife zones is often compromised by parasitic infestations. This study aimed to assess the prevalence and epidemiology of ecto- and endoparasites among cattle inhabiting a semi-arid wildlife zone, examining the influence of age, breed, and tolerance. A total of 320 cattle were surveyed, and a representative sample of 36 animals (using random selection methods) from different age groups (calves, weaners, adults) and breeds (Brahman, Angus, Beef master) were chosen for detailed parasite analysis. Parasite identification was conducted with veterinary assistance and supplemented by relevant literature. A high prevalence of ectoparasites was observed, with four prominent hard tick species identified which included the Rhipicephalus (Boophilus) decloratus (27.44 ticks per animal), Rhipicephalus appendiculatus (10.50), Amblyomma variegatum (0.83), and Hyalomma spp (0.44). Additionally, internal parasites were identified including Fasciola spp (0.14), Fasciola eggs (1.89), Trematode eggs (2.81), Strongyle eggs (2.50), and Ascaris lumbricoides (0.14). Weaners exhibited a higher susceptibility to parasitic burdens, while the Beef master breed displayed a significantly low parasite count compared to other breeds. Brahman and Angus breeds demonstrated tolerance to parasites, with minimal recorded mortality. Although a direct correlation between wildlife and cattle diseases was not established, the study investigated potential shared parasites with commonly encountered wildlife species in the zone. These findings highlight the importance of targeted parasite control programs, particularly for weaners, to minimize health risks and enhance herd well-being in wildlife zones. Implementing parasite management strategies tailored to breed-specific tolerances and age groups is crucial for optimal cattle health and productivity in such environment. [ABSTRACT FROM AUTHOR]

Purpose : Rhipicephalus (Boophilus) microplus is one the most significant ectoparasite in cattle farming in tropical and subtropical regions, causing problems to livestock health worldwide. The control of this ectoparasite primarily relies on the use of synthetic acaricides. However, the emergence of acaricide resistance has stimulated the search for new control alternatives, including phytocompounds with acaricidal and insecticidal potential. The aim of this study was to evaluate the acaricidal potential of Lavandula dentata essential oil against the engorged females of R. (B.) microplus. Methods: Engorged females were obtained from infested bovines in dairy farms in Pernambuco, Brazil. L. dentata essential oil was extracted, and adult immersion test assays were performed using the following oil concentrations: 0.2%, 0.4%, 0.6%, 0.8%, and 1%. Results : L. dentata essential oil at a concentration of 1% was lethal to all engorged females, and concentrations of 0.6% and 0.8% caused mortality of 98.6% and 99.1%, respectively. These concentrations disrupted the reproductive capacity of engorged females, reducing oviposition by more than 90% and preventing egg hatching by over 87%. Conclusion: The data revealed that L. dentata essential oil possesses effective pharmacological properties against R. (B.) microplus and could be used for tick control following in vivo evaluation, thus contributing to mitigating the negative impacts of synthetic acaricide use. [ABSTRACT FROM AUTHOR]

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Objective: The abundance of tick populations in South Africa represents a probable risk for both animal and human health. Rickettsia spp. and Borrelia spp. are well-known agents of emerging human tick-borne infectious diseases worldwide. Nevertheless, the epidemiology of their infections has been underreported in South Africa. Therefore, this study aimed to profile zoonotic Rickettsia and Borrelia species from ticks infesting domesticated animals in the Eastern Cape, South Africa. Materials and Methods: Morphological and molecular identification techniques were conducted on 1,200 tick samples collected from domestic animals before screening for the target bacterial pathogens. The molecular identification of the tick samples was based on the amplification of the 12S rRNA mitochondrial Deoxyribonucleic acid. At the same time, those of Rickettsia and Borrelia species were carried out by amplifying fragments of gltA and ompB genes for Rickettsia and flaB gene for Borrelia spp. Thereafter, the positive amplicons for Rickettsia ompB were sequenced and further analyzed. Borrelia PCRs were negative; therefore, sequencing could not be performed. Results: Eight species of ticks belonging to three genera; Rhipicephalus, Amblyomma, and Haemaphysalis, were identified. A total of 27% (320/1,200) samples were confirmed positive for Rickettsia, of which 23% (74/320) were positive for ompB genes. Phylogenetic analysis of ompB revealed a high homology to rickettsial reference strains from GenBank, with no positive result for Borrelia. The generated sequences showed homology with R. africae-KX227790 (100%), R. parkeri-KY113111 (99.8%), R. peacockii (99.3%), and R. slovaca-JX683122 (99.1%) representative sequences in GenBank. Conclusion: The findings from this study revealed that ticks harbored Rickettsia species with possible zoonotic potential. [ABSTRACT FROM AUTHOR]

Objective: The Amblyomma mixtum tick is one of the main parasites affecting cattle in Mexico. Epidemiological records of A. mixtum in leading states in the national cattle industry, such as Jalisco, Chiapas, Michoacán, Tabasco, and Veracruz, are outdated since this tick species was previously classified as A. cajennense. The objective was to update the records of the A. mixtum tick in the states of Jalisco, Chiapas, Michoacán, Tabasco, and Veracruz, as well as the main ixodicide molecules used for its control. Methodology: From March 2022 to July 2023, ticks were collected from cattle in 46 bovine production units (BPUs) distributed in the states mentioned above. Identification was performed using standardized taxonomic keys. Scanning electron microscopy was performed on specimens corresponding to A. mixtum. Results: Out of a total of 619 specimens of the genus Amblyomma from 22 PBUs, it was confirmed that 100% correspond to the species A. mixtum. Amitraz, an ixodicide molecule belonging to the chemical class of amidines, was used in 63.2% of the BPUs where the presence of A. mixtum was also reported. Conclusions: This research confirms cattle infestation with A. mixtum in states with the highest cattle production in Mexico. Further studies with a focus on resistance and extension are required to prolong the usefulness of available tools, including ixodicides, for integrated control of A. mixtum infestations where this tick infests cattle in Mexico. [ABSTRACT FROM AUTHOR]

Simple Summary: In the northwestern Colombian Amazon, ticks are a significant issue for dairy cattle in the northwestern Colombian Amazon, affecting the animals' health and the productivity of farms. Our study aimed to identify the most common types of ticks in this area and how environmental factors such as temperature and rainfall affect their numbers. We discovered that only one kind of tick dominates in this region. Interestingly, we found that these ticks are more abundant during warmer and drier months, especially affecting a certain type of cattle more than others. Based on our findings, we recommend that farmers implement tick control measures directly on the cattle and in the pastures where these animals graze more frequently during warmer periods. This dual approach is crucial for effectively managing tick populations, promoting animal health, and ensuring dairy farms' efficient operation. This research is valuable for local farmers and could also benefit agricultural practices in similar environments worldwide. Cattle ticks are a significant health concern in tropical livestock production due to their hematophagous behavior and potential as vectors for human and animal pathogens. In this study, we investigated the tick population present in dairy cattle production, calves, and grazing areas of livestock systems in the northwestern Colombian Amazon. Identification was based on taxonomic keys and molecular markers. Phylogenetic relationships were established using mitochondrial COX1 and 16S genes. Population structure analysis was performed considering age, racial type (B. indicus vs. B. taurus), and the influence of environmental factors and the geomorphological landscape on tick population dynamics. Our findings revealed the presence of a single tick species, with a unique haplotype identified for each mitochondrial gene assessed. Phylogenetic analysis classified the found species within Clade A of the Rhipicephalus microplus complex. Ticks were more prevalent during periods of low rainfall and high temperature, and B. taurus cows exhibited the highest tick abundance. Thus, these results provide insights into the population characteristics and distribution of the tick species present in dairy cattle production systems in the northwestern part of the Colombian Amazon. This information is fundamental for developing targeted strategies based on seasonal variation and host characteristics to mitigate tick infestation severity in the region. [ABSTRACT FROM AUTHOR]

Ticks serve as vectors and reservoirs of various Borrelia species, potentially causing diseases in humans and animals. Mazandaran, a fertile green land in northern Iran, provides ample grazing grounds for livestock and harbors at least 26 hard tick species. This study investigated Borrelia infection in hard ticks from forest areas in this region and compared their genetic identity with the species data in the GenBank database. A total of 2,049 ticks were collected manually from mammalian hosts or using dragging and flagging methods. These ticks were then grouped into 190 pools and 41 individuals based on host, species, developmental stage, and gender. A real-time PCR (qPCR) detected Borrelia DNA in 26 pools from female, male, and nymph of Rhipicephalus annulatus (n = 17) and Ixodes ricinus (n = 9) ticks and one individual female Haemaphysalis punctata tick. The generated partial flaB and glpQ sequences from qPCR-positive Rh. annulatus ticks exhibited the highest identities of 98.1-100% and 98.2% with Borrelia theileri and closely related undefined isolates. Additionally, in phylogenetic analysis, these sequences clustered within well-supported clades with B. theileri and the closely related undefined isolates from various geographic regions, confirming the presence of B. theileri in the north of Iran. Divergence in B. theileri flaB and glpQ sequences across various geographical areas suggests potential subspeciation driven by adaptations to different tick species. This divergence in our flaB sequences implies the possible introduction of B. theileri-infected ticks from different geographical origins into Iran. [ABSTRACT FROM AUTHOR]

Ixodes ricinus is a vector of several pathogens of public health interest. While forests are the primary habitat for I. ricinus, its abundance and infection prevalence are expected to vary within forest stands. This study assesses the spatio-temporal variations in tick abundance and infection prevalence with three pathogens in and around a peri-urban forest where human exposure is high. Ticks were sampled multiple times in 2016 and 2018 in multiple locations with a diversity of undergrowth, using the consecutive drags method. Three zoonotic pathogens were screened for, Borrelia burgdorferi s.l., Coxiella burnetii, and Francisella tularensis. The influence of season, type of site and micro-environmental factors on tick abundance were assessed with negative binomial generalized linear mixed-effects models. We collected 1642 nymphs and 181 adult ticks. Ticks were most abundant in the spring, in warmer temperatures, and where undergrowth was higher. Sites with vegetation unaffected by human presence had higher abundance of ticks. Forest undergrowth type and height were significant predictors of the level of tick abundance in a forest. The consecutive drags method is expected to provide more precise estimates of tick abundance, presumably through more varied contacts with foliage. Borrelia burgdorferi s.l. prevalence was estimated from pooled ticks at 5.33%, C. burnetii was detected in six pools and F. tularensis was not detected. Borrelia afzelii was the dominant B. burgdorferi genospecies. Tick abundance and B. burgdorferi s.l. infection prevalence were lower than other estimates in Belgian forests. [ABSTRACT FROM AUTHOR]

Parasites are typically concentrated on a few host individuals, and identifying the mechanisms underlying aggregated distribution can facilitate a more targeted control of parasites. We investigated the infestation patterns of hard ticks and chigger mites on two rodent species, the striped field mouse, Apodemus agrarius, and the lesser ricefield rat, Rattus losea, in Taiwan. We also explored abiotic and biotic factors that were important in explaining variation in the abundance of ticks and chiggers on rodent hosts. Ticks were more aggregated than chiggers on both rodent species. Factors important for the variation in parasitic loads, especially biotic factors, largely differed between ticks and chiggers. Variation partitioning analyses revealed that a larger proportion of variation in chiggers than in ticks can be explained, especially by abiotic factors. If, as proposed, the higher number of parasites in males is due to a larger range area or immunity being suppressed by testosterone, when A. agrarius males host more ticks, they are expected to also host more chiggers, given that chiggers adopt a similar host finding approach to that of ticks. Instead, the similar abundance of chiggers in male and female A. agrarius implies that a large home range or suppressed immunity does not predispose males to inevitably host more parasites. More variations were explained by abiotic than biotic factors, suggesting that controlling practices are more likely to be successful by focusing on factors related to the environment instead of host traits. Our study indicated that the extent of parasitism is rarely determined by a sole factor, but is an outcome of complex interactions among animal physiology, animal behavior, characteristics of parasites, and the environments. [ABSTRACT FROM AUTHOR]

The bacterial agent of Lyme disease, Borrelia burgdorferi, exists in an enzootic cycle by adapting to dissimilar mammalian and tick environments. The genetic elements necessary for host and vector adaptation are spread across a bacterial genome comprised of a linear chromosome and essential linear and circular plasmids. The promoter trap system, In Vivo Expression Technology (IVET), has been used to identify promoters of B. burgdorferi that are transcriptionally active specifically during infection of a murine host. However, an observed infection bottleneck effect in mice prevented the application of this system to study promoters induced in a tick environment. In this study, we adapted a membrane-based in vitro feeding system as a novel method to infect the Ixodes spp. vector with B. burgdorferi. Once adapted, we performed IVET screens as a proof of principle via an infected bloodmeal on the system. The screen yielded B. burgdorferi promoters that are induced during tick infection and verified relative expression levels using qRT-PCR. The results of our study demonstrate the potential of our developed in vitro tick feeding system and IVET systems to gain insight into the adaptive gene expression of the Lyme disease bacteria to the tick vector. [ABSTRACT FROM AUTHOR]

Ixodes ricinus ticks are vectors of a plethora of pathogens. The purpose of this study was to screen 398 I. ricinus ticks for a variety of pathogens. Following the pooling, homogenization, and extraction of total nucleic acids, a real-time PCR was applied for the detection of a panel of tick-borne pathogens, while additional conventional PCRs combined with Sanger sequencing were applied for the detection of viruses and typing of Rickettsia and Borrelia species. At least one pathogen was detected in 60 of the 80 (75%) tick pools. Rickettsia spp. predominated, as it was detected in 63.75% of the pools (51/80; MIR 12.81%), followed by Borrelia spp. (35 pools (45%); MIR 8.79%), while Anaplasma phagocytophilum was detected in 2 pools (2.5%, MIR 0.5%). The ticks of six Rickettsia-positive pools were tested individually (from stored half-ticks); all sequences were identical to those of R. monacensis. Similarly, the ticks of six Borrelia-positive pools were tested individually, and it was shown that four belonged to the genospecies Borrelia garinii and two to Borrelia valaisiana. Phleboviruses were detected in 3 pools (3.75%; MIR 0.75%), with sequences clustering in the Ixovirus genus, while nairoviruses were detected in 7 pools (8.75%; MIR 1.76%), with one sequence clustering in the Orthonairovirus genus, and six clustering in the Norwavirus genus. Although a small number of ticks from only one area in Greece were tested, a variety of pathogens together with recently identified viruses were detected, prompting further studies in ticks and surveillance studies in humans. [ABSTRACT FROM AUTHOR]