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• Variations is explained by ecological and climatic characteristics than with the meteorological variations. • Only night temperatures would explain variations in oviposition activity. • Variables are strong affected by Ecoregional, and ecoregional effects are stronger in small towns than in large cities. • Ae. aegypti first recorded at High Monte ecoregion. Probably result of town size effect. (i. e. Cafayate a city has 18,000 inhabitants where Ae. aegypti was detected, and next town San Carlos (7000 habitants, 21 km away, 20 min by road). Mosquitoes were not detected. We strongly recommend carry out new studies to verify this. We assessed the presence of Aedes aegypti in five ecorregions of Salta province and compared the oviposition activity of Ae. aegypti using ovitraps in towns of two contrasting ecoregions (yungas and Chaco dry forests) in the province of Salta, Argentina, a major contrast in these ecoregions are rain patterns and altitude. Our aim was to estimate how oviposition activities were associated with the ecoregion and site scale local environmental variables. Mosquito oviposition activity was monitored weekly during the summer using ovitraps. Predictor variables were ecoregion, town, and meteorological variables. The effect of the predictor variables was measured on the response variables using multi-model inference. Besides yungas, the presence of Aedes aegypti was confirmed in towns of dry Chaco and High Monte. The only factor that had a significant effect on the presence of eggs in the ovitraps was the ecoregion, with the frequency of positives being higher in yungas. For the number of eggs, the ecoregion, the night temperature of the first week and the NDVI would explain said variable. Overall, results indicate that the variations between towns would be more related with their ecological and climatic characteristics than with the more immediate meteorological variations. [Display omitted] [ABSTRACT FROM AUTHOR]

Following the Public Health Emergency of International Concern declared on Zika by the World Health Organization during 2016, the Indian Council of Medical Research carried out nationwide vector surveillance for Zika and Dengue viruses (ZIKV and DENV) in India as a preparedness measure in 2016–19. High-risk zones distributed to 49 Districts in 14 states/union territories were included in the study. Seven ICMR institutions participated, following a standard operating protocol. Aedes specimens sampled weekly were processed by multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) for ZIKV/DENV and random samples crosschecked with real-time RT-PCR for ZIKV. Altogether, 79 492 Aedes specimens in 6492 pools were processed; 3 (0.05%) and 63 (0.97%) pools, respectively, were found positive for ZIKV and DENV. ZIKV infections were recorded in Aedes aegypti sampled during the 2018 sporadic Zika outbreak in Jaipur, Rajasthan. However, these belonged to the Asian lineage of the virus, already circulating in the country. Both Ae. aegypti and Aedes albopictus distributed to 8 states/union territories were found to be infected with DENV. Both sexes of Ae. albopictus were infected, indicating transovarial transmission. This investigation evinced no active transmission of the American lineage-pandemic Zika virus in India during the pandemic period. [ABSTRACT FROM AUTHOR]

Tick abundance and diagnosed cases of tick-borne diseases have been increasing in the United States. American black bear (Ursus americanus) populations have also been increasing in the eastern United States. As a competent host of several species of ticks and a mammal capable of traveling long distances, the role of black bears as hosts for ticks requires further evaluation. Ectoparasite surveys were conducted on black bears in Pennsylvania to evaluate tick presence, abundance, spatial distribution, and association with Sarcoptes scabiei, the etiological agent of sarcoptic mange , on bears to better understand their role in tick ecology and to improve on-host surveillance techniques. Tick burden was evaluated using standard area sampling (10.16 × 10.16 cm squares) on pre-designated body regions on black bears from June 2018–December 2019. In total, 278 unique individual black bears were evaluated, with all ticks identified as Ixodes scapularis (n = 1976; 76.7% adults, 23.3% immatures). Tick presence differed by body region on bears, with the highest percentage of tick observations located on bear ears and muzzle. Ticks also partitioned on black bears by life-stage, with immature ticks primarily recorded on the lower extremities of bears and adult ticks primarily recorded on the front-quarters of bears. This includes the first known record of I. scapularis larvae parasitizing black bears, and observations of all three mobile life-stages concurrently parasitizing bears. Tick abundance was also statistically significant dependent on season, with the highest abundance of ticks recorded in spring and lowest abundance in fall. Adult ticks were less likely to be present on bears with mange. These data reveal the important role black bears may serve in tick ecology and dispersal as all three mobile life-stages of I. scapularis were found parasitizing a mammal capable of traveling far distances in a region with high numbers of Lyme disease cases. [Display omitted] • First record of Ixodes scapularis larvae parasitizing black bears. • All three I. scapularis mobile life-stages concurrently parasitizing black bears. • I. scapularis life-stage segregation on black bears. • Standardized tick survey findings can be used to improve on-host surveillance. • Bears with sarcoptic mange less likely to have adult ticks present. [ABSTRACT FROM AUTHOR]

Interactions between humans and ticks are often measured indirectly, using surveillance of tick population abundance and pathogen prevalence, or reported human disease data. We used data garnered as part of a free national citizen science research effort to describe actual human exposures to ticks in California. Human-biting ticks (n = 1,905) submitted for identification were predominantly western black-legged ticks (Ixodes pacificus) (68%), American dog ticks (Dermacentor variabilis) (24%), and Pacific Coast ticks (Dermacentor occidentalis) (7%). Tick exposure occurred predominantly during recreational use of the outdoors, rather than exposure near the home environment. Tick submissions peaked in May, but human exposure to ticks occurred throughout the year. Adult I. pacificus were most frequently found on humans during March-May, though previous research demonstrates that questing adults on vegetation are more abundant earlier in the winter. [ABSTRACT FROM AUTHOR]

As a result of shifts in the habitable range of ticks due to climate change and the ongoing threat of exotic tick species introductions, efficient surveillance tools for these pests and disease vectors are needed. Wild pigs are habitat generalists, distributed throughout most of the United States, and often hunted recreationally or removed as part of management programs, making them potentially useful sentinel hosts for ticks. We compared ticks collected from captured wild pigs and standard tick dragging methods on a south-central Florida cattle ranch from May 2015–August 2017. Three hundred and sixteen wild pigs were surveyed, and 84 km spanning three habitat types (seminative pasture, improved pasture, and hammock) were dragged. In total, 1023 adults of four species ( Amblyomma auricularium , Amblyomma maculatum , Dermacentor variabilis , and Ixodes scapularis ) were collected from wild pigs, while 39 adults of three species ( A. auricularium , A. maculatum , and I. scapularis ) were collected from drags. Only one immature specimen, a nymph, was collected from a pig, while dragging collected 2808 larvae and 150 nymphs. Amblyomma maculatum comprised 96% of adults collected from pigs, while A. maculatum , I. scapularis, and A. auricularium comprised 38%, 33%, and 28% of adults collected from drags, respectively. Adults of all tick species found on drags were found on pigs, and wild pig surveillance detected adults of an additional species not found on drags. Dragging was far superior for collection of immatures but not for adults of most species found in this study. These findings suggest wild pigs could be used as a sentinel for the detection of tick species. When combined with ongoing wild pig research, hunting, or management, wild pig surveillance can provide an effective method to survey for adult tick presence of some species of interest and may assist in tracking the range expansion of some tick species. [ABSTRACT FROM AUTHOR]

Kentucky experiences some of the highest incidence rates for ehrlichiosis nationwide. Ehrlichiosis is a bacterial infection caused primarily by the pathogen Ehrlichia chaffeensis and can be transmitted to humans through the bite of an infected tick, notably Amblyomma americanum. Amblyomma americanum , the lone star tick, is common to Kentucky and much of the southeast, but has expanded farther north in recent years. As an abundant and aggressive nondiscriminatory biter, this species is of major public health concern for transmission of pathogens to humans. As this vector's range expands, surveillance remains a necessary tool providing data that allows researchers to track this expansion over time. The historical information on tick distribution in Kentucky is variable with very little data on a statewide scale. From January 2019 to December 2020, we conducted surveillance for A. americanum in Kentucky through field collections and the establishment of a statewide tick submission program with the help of the Kentucky Department for Public Health and screened for E. chaffeensis on a county-level throughout the state. We collected 5,726 A. americanum ticks in 77 counties and detected E. chaffeensis in 32 counties. The minimum infection rate was 1.8%. With the expansion of A. americanum and increasing cases of tick-borne diseases, future surveillance is needed to monitor this important tick vector over time. [ABSTRACT FROM AUTHOR]

Lyme disease is the most common tick-borne illness in the United States and is becoming more prevalent each year. It is transmitted to humans and animals through the bites of Ixodes scapularis ticks infected with Borrelia burgdorferi in the eastern United States, I. pacificus in the western U.S, and I. ricinus in Europe and Asia. In Kentucky, where Lyme disease is non-endemic, the number of reported human cases in 2010 totaled five. In 2019, that number had increased by over 300%. Identifying the distribution of I. scapularis populations infected with B. burgdorferi is important data for effective prevention strategies and an important first step in monitoring disease spread. In collaboration with the Kentucky Department for Public Health, we performed surveillance for I. scapularis throughout the state of Kentucky using both active and passive surveillance methods. Diagnostic testing for the identification of B. burgdorferi (sensu stricto) was also conducted. We identified 457 I. scapularis ticks from March 2019 to December 2020 from 32 counties in Kentucky. B. burgdorferi was detected in I. scapularis populations collected from 14 different counties. These results add to the little data that exists in Kentucky on I. scapularis and B. burgdorferi distribution. [ABSTRACT FROM AUTHOR]

Highlights: [•] SYBR Green I based quantitative RT-PCR assay was developed for emerging CHIKV. [•] Field surveillance confirmed the vectorial potential of Aedes aegypti in India. [•] Oral infection of Aedes aegypti with CHIKV revealed 100% infection and dissemination rate. [•] A transmission rate of 60% was also observed in Aedes aegypti. [•] qRT-PCR is a remarkable tool for surveillance of virus activity in mosquitoes. [ABSTRACT FROM AUTHOR]

• The present study is the first surveillance of bluetongue virus vector species in Thailand. • Bluetongue virus was detected from four species of Culicoides biting midges by RT-PCR analyses. • The potential bluetongue virus vectors in western Thailand were C. orientalis, C. imicola, C. oxystoma , and C. fulvus. • DNA barcoding is an effective method to identify atypical variants of Culicoides species. Biting midges of the genus Culicoides Latreille are biological vectors of bluetongue virus (BTV), a member of family Reoviridae, genus Orbivirus. About 30 species of Culicoides have been identified as competent BTV vectors worldwide. Even though high seroprevalence of BTV has been reported among livestock ruminants from western Thailand, the Culicoides species which contribute to BTV transmission remain unclear. In the present study, Culicoides were collected from eight sampling sites, located in two BTV prevalent provinces in western Thailand. Adult Culicoides were identified using wing morphology and cytochrome c oxidase subunit I (COI) mtDNA molecular marker. A total of 9,677 Culicoides specimens belonging to 7 subgenera, 3 species groups, and 23 species were identified. After comparing sequencing results with available data from GenBank, COI sequences of five species were reported for the first time from Thailand. The most abundant potential BTV vector species collected were C. peregrinus , followed by C. orientalis, C. imicola, C. oxystoma , and C. fulvus. Out of 72 Culicoides pools, 9 pools (4 from C. orientalis , 2 from C. imicola , 2 from C. oxystoma , and 1 from C. fulvus) were positive by BTV RT-PCR analyses. These results are new to Culicoides BTV vector knowledge in Thailand and will contribute to further BTV studies in this particular region. [ABSTRACT FROM AUTHOR]

Abstract: Sylvatic triatomines of the genus Rhodnius commonly fly into houses in Latin America, maintaining the risk of Chagas disease transmission in spite of control efforts. In the recent past, adult bugs collected inside houses in central Brazil were identified as R. prolixus, a primary disease vector whose natural geographical range excludes this region. Three nearly sibling species (R. neglectus, R. nasutus, and R. robustus), secondary vectors with limited epidemiological significance, occur naturally south of the Brazilian Amazon. The specific status of Rhodnius specimens found inside houses in central Brazil is therefore an epidemiologically important (and still debated) issue. We used wing and head geometric morphometrics to investigate the taxonomic status of 230 adult specimens representing all four ‘R. prolixus group’ species (19 populations from palm trees, domiciles, and reference laboratory colonies). Discriminant analyses of shape variation allowed for an almost perfect reclassification of individuals to their putative species. Shape patterning revealed no consistent differences between most specimens collected inside houses in central Brazil and R. neglectus, and showed that R. robustus and R. neglectus occur sympatrically (and fly into houses) in southern Amazonia. Furthermore, all Brazilian specimens clearly differed from our reference R. prolixus population. Using geometric morphometrics, we confidently ascribed individual triatomines to their species within the problematic ‘R. prolixus group’, illustrating the potential value of this approach in entomological surveillance. Our results strongly support the idea that R. neglectus, and not R. prolixus, is the species invading houses in central Brazil. [Copyright &y& Elsevier]

• Vector surveillance will be critical in the move towards onchocerciasis elimination. • Host Decoy Traps (HDTs) caught 60 times more Simulium than esperanza window traps. • A single infectious Onchocerca species larva was dissected from a sample caught by HDT. • HDTs may support onchocerciasis surveillance in elimination campaigns. Onchocerciasis elimination is within reach in many countries but requires enhanced surveillance of the Simulium vectors of Onchocerca volvulus. Collection of sufficient numbers of adult Simulium to detect infective O. volvulus larvae is hindered by limited sampling tools for these flies. Here, we tested for the first time the Host Decoy Trap (HDT), an exposure free method previously developed for Anopheles vectors of malaria parasites, as a potential sampling tool for adult Simulium. In three replicates of a randomized Latin square experimental design, the HDT was compared to Human Landing Catches (HLC) and the Esperanza Window Trap (EWT). A total of 8,531 adult S. damnosum sensu lato blackflies (S. squamosum group) were found in catches from the three different trapping methods. The HDT (mean catch 533 ± 111) caught significantly more S. squamosum than the EWT (mean catch 9.1 ± 2.2), a nearly 60-fold difference. There was no significant difference between the HLC (mean catch 385.6 ± 80.9) and the HDT. Larvae indistinguishable from those of O. volvulus were dissected from 2.86% of HDT samples (n = 70) and 0.35% of HLC samples (n = 285); a single infective third-stage larvae (L3) was found during dissection of a sample from the HDT. Owing to its very high capture rate, which was comparable to the HLC and significantly greater than EWT, alongside the presence of infected flies in its catch, the HDT represents a potentially valuable new tool for blackfly collection in elimination settings, where thousands of flies are needed for parasite screening. Host Decoy Traps are a potential surveillance tool for Simulium vectors in onchocerciasis elimination campaigns. [Display omitted] [ABSTRACT FROM AUTHOR]

• Eighteen cases of Chagas disease were confirmed serologically in the semiarid region of Rio Grande do Norte state, Brazil, with two deaths reported. • Only 7.5% of residents in the outbreak area admitted knowledge that Chagas disease can also be acquired orally;. • Twelve percent of dwellings were found to be suitable for triatomine colonization;. • Thirteen percent of people reported they may have been bitten by triatomines in the last three years;. • The physical proximity between humans and triatomine populations with high trypanosoma cruzi prevalence represents a risk factor to further oral/vector contaminations. Chagas disease is a neglected tropical disease strongly associated with low socioeconomic status, affecting nearly 8 million people – mainly Latin Americans. The current infection risk is based on acute case reports, most of which are typically associated with oral transmissions. In the semi-arid region of Northeastern Brazil, serious outbreaks of this transmission type have surged in the last years. One of those occurred in 2016 in the state of Rio Grande do Norte. Rural residents of four municipalities surrounding Marcelino Vieira ingested sugar cane juice – which was probably ground with Trypanosoma cruzi -infected insects. Eighteen cases of Chagas disease were confirmed serologically, with two deaths reported. Socioeconomic information, schooling of residents and the structure of peridomestic and domestic environments in the rural area of Marcelino Vieira, along with entomological indicators, were investigated to understand better the factors related to the outbreaks in this region. We found triatomines (mainly Triatoma brasiliensis) in 35% (24/67) of domiciliary units and all rocky outcrops inspected (n = 7). Overall, 25% (91/357) of examined T. brasiliensis were infected by T. cruzi in artificial ecotopes, with almost the same prevalence in the sylvatic environment (22%; 35/154). Among all ecotopes investigated, wood/tile/brick piles were the ones linked to high insect infestations and triatomine T. cruzi infection prevalence. Ninety-five percent of people interviewed recognized the triatomines and knew the classic route of transmission of disease – triatomine bite-dependent. However, only 7.5% admitted knowledge that Chagas disease can also be acquired orally – which poses a risk this transmission route currently recognized. Here, we highlight the physical proximity between humans and triatomine populations with high T. cruzi infection prevalence as an additional risk factor to oral/vector contaminations. In sum, residents have low income, low level of education, and/or a willful disregard for the routes of Chagas disease transmission (specifically oral transmission), a combination of factors that may have favored the Chagas disease outbreak. We here provide recommendations to avoid further outbreaks. [ABSTRACT FROM AUTHOR]