West Bengal, India, is inhabited by abundance and variety of insects that triggers sensitization in some humans to inhalant allergens and/or insect stings/venoms. Lack of research on this topic prevented accurate diagnosis and proper follow-up treatments to patients suffering from insect-induced allergies.The aim of our study was to identify the allergy-causing insects and evaluate resulting sensitization among a study population in West Bengal, India.The skin prick test (SPT) evaluated sensitivity of 450 patients who sought treatment at the Allergy and Asthma Research Center from July 2017 to June 2018. Eight insect allergens were tested: Common Black Ant (Lasius niger, Linnaeus 1758), Fire Ant (Solenopsis invicta, Buren 1972), Honey Bee (Apis cerana indica, Fabricius 1798), Common Wasp (Vespula vulgaris, Linnaeus 1758), Mosquito (Aedes aegypti, Linnaeus in Hasselquist 1762), American Cockroach (Periplaneta americana, Linnaeus 1758), House Fly (Musca domestica, Linnaeus 1758), and Grasshopper (Gesonula punctifrons, Stal 1861). From a total of 450 patients evaluated, 370 patients had positive SPT reaction from at least one of the 8 insect allergens tested. Sensitivity to some Hymenoptera insects (common black ant, 87.62%; fire ant, 84.59%; and honey bee, 67.02%) was found in higher proportion than non-Hymenoptera group (mosquito, 66.67%; American cockroach, 33.33%; house fly, 10.41%; and grasshopper, 5.14%). There was significant difference in sensitivity among child, adolescent, and adult (P < 0.001). While female patients showed more sensitivity than males to SPT, the difference was statistically insignificant. In regards to occupation, farmers and bee keepers were most sensitive of field workers sensitive to Hymenoptera-derived allergens.

The Asian mosquitoes, Aedes albopictus (Skuse) and Aedes japonicus japonicus (Theobald), have invaded North America, Europe, and other regions since the late 20th century. In invasive ranges, Ae. albopictus has well been recognized as urban, domestic species, whereas views about the macrohabitats of Ae. j. japonicus are inconsistent. Previous reports in Japan suggest the disappearance of Ae. j. japonicus from metropolises. However, container-mosquito larvae have not been inspected simultaneously for various macro and microhabitats in metropolises in Japan. The current study in Fukuoka City, a metropolis in southwest Japan, confirmed the absence of Ae. j. japonicus irrespective of macrohabitats (temples with graveyards, shrines, public graveyards, cultivated bamboo groves, and urban forests, all within the area densely inhabited by humans) and microhabitats (container types). In contrast, Ae. albopictus was dominant throughout the macro and microhabitats except forest tree holes rich with competitive species. Past records indicate the disappearance of Ae. j. japonicus from metropolitan Fukuoka within the last 70 yr. Based on careful examination of available evidence, we concluded that 1) both species benefit from human-made environments with artificial containers free from competitors, 2) Ae. j. japonicus disappeared due to hot, dry summer conditions facilitated by urban heat-island effects and a decrease in favored mammal hosts, and 3) Ae. albopictus has proliferated with higher tolerance to hot, dry climate and a wider blood-feeding host-range including humans. This difference is important for efficient control of each species as well as predicting and preventing the expansion into new distribution ranges.

Insects are ectothermic organisms; hence, all aspects of their biology are strongly influenced by ambient temperatures. Different insect species respond differently with phenotypic plasticity and/or genetic adaptation to changing temperatures. Here, we tested the thermal adaptation of the house fly and three of its parasitoids species by comparing life-history parameters in populations from a hot climate region (Jordan Valley) and from a moderate-climate region (Galilee). No significant differences were found between the two house fly populations, both under hot and moderate experimental conditions. Life-history parameters of the parasitoids (Muscidifurax raptor Girault & Sanders, Spalangia endius Walker, and Spalangia cameroni Perkins [Hymenoptera: Pteromalidae]) varied markedly between origins, species, sexes, and experimental conditions. Of the three species tested, only M. raptor collected in the Jordan Valley proved better adapted to experimental heat conditions, compared to its counterpart population that was collected in the Galilee. Additionally, we tested the effect of elevating temperatures on a house fly lab population for 17 consecutive generations and found no evidence for heat adaptation. We discuss our results in the context of house fly control and global warming.

The northern fowl mite (NFM) Ornithonyssus sylviarum Canestrini and Fanzago is a blood-feeding ectoparasite found on many wild bird species and is a pest of poultry in the United States. It is unknown where NFM infestations of poultry originate, which has made it difficult to establish preventative biosecurity or effective control. We used microsatellite markers to evaluate genetic variation within and among NFM populations to determine routes of introduction onto farms and long-term persistence. We compared NFM from flocks of chickens (Gallus gallus) on different farms in California, Washington, and Georgia, and we compared NFM collected over a 5-yr interval. On three farms we collected NFM from chickens and house sparrows (Passer domesticus) nesting on each farm, which we used to assess movement between host species.There was strong genetic structure among mites from different poultry farms and low estimates of migration between farms. There were significant differences between mites on chickens and house sparrows on two farms where sparrows nested near flocks, indicating no exchange of mites. Only one farm showed evidence of NFM movement between chickens and sparrows.There was high genetic similarity between mites collected 5 yr apart on each of two farms, indicating that NFM infestations can persist for long periods.The genetic patterns did not reveal sources of NFM infestations on chicken farms.The data suggest that NFMs are strongly differentiated, which likely reflects periodic population declines with flock turnover and pesticide pressure.

In the United States, tick-borne diseases are increasing in incidence and cases are reported over an expanding geographical area. Avoiding tick bites is a key strategy in tick-borne disease prevention, and this requires current and accurate information on where humans are at risk for exposure to ticks. Based on a review of published literature and records in the U.S. NationalTick Collection and National Ecological Observatory Network databases, we compiled an updated county-level map showing the reported distribution of the American dog tick, Dermacentor variabilis (Say). We show that this vector of the bacterial agents causing Rocky Mountain spotted fever and tularemia is widely distributed, with records derived from 45 states across the contiguous United States. However, within these states, county-level records of established tick populations are limited. Relative to the range of suitable habitat for this tick, our data imply that D. variabilis is currently underreported in the peer-reviewed literature, highlighting a need for improved surveillance and documentation of existing tick records.

Passive and active surveillance for the blacklegged tick, Ixodes scapularis Say, in the Canadian province of Saskatchewan was conducted over a 9-yr period (2009–2017). More than 26,000 ixodid ticks, representing 10 species, were submitted through passive surveillance. Most (97%) of these were the American dog tick, Dermacentor variabilis (Say). Of the 65 I. scapularis adults submitted, 75% were collected from dogs. Infection rates of Borrelia burgdorferi, Anaplasma phagocytophilum, and Babesia microti in I. scapularis were 12%, 8%, and 0%, respectively. Although the I. scapularis submitted by passive surveillance were collected from five of seven ecoregions in central and southern Saskatchewan, they were most frequent in the Moist Mixed Grassland and Aspen Parklands. In contrast, no I. scapularis were collected from the extensive field sampling conducted at multiple sites in different ecoregions across the province. Hence, there is no evidence of I. scapularis having established a breeding population in Saskatchewan. Nonetheless, continued surveillance for blacklegged ticks is warranted given their important role as a vector of medically and veterinary important pathogens, and because they have recently become established across much of the southern portions of the neighboring province of Manitoba.

Ecological succession of necrophilous insects follows a predictable sequence, related to their differential attraction to changing odor profiles associated with carrion and colonizing insects. However, the dependency of insect arrival on the duration of the carrion's residency at a location has not been investigated. To assess the fidelity of necrophilous insects to carrion of specific decomposition ages, independent of its location, we monitored the decomposition of neonate pigs in one field and then simultaneously relocated carcasses of different decomposition ages to an ecologically similar but remote field. We examined the effects of decomposition age and relocation on the assembly of the necrophilous insect community, using a novel vented-chamber trap, which excluded all sensory cues except odors. Community composition differed over a 4-d decomposition period, showing that insects were differentially attracted to pigs of different decomposition ages. There was overall concordance between respective decomposition ages in the two fields, with similar relative abundances of taxa before and after transfer. Although different decomposition ages continued to attract different insects, differentiation of the necrophilous insect communities relative to the age of decomposition was less pronounced after transfer. The results of this study demonstrate that translocating a decomposing body to a new, but geographically and ecologically similar location continues the predicted insect succession, albeit with greater variance, based on olfactory cues alone. Several rare taxa were sampled only prior to relocation, including the first documentation of the invasive hairy maggot blow fly, Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae), in central North Carolina.

Testing behavioral response to insecticidal volatiles requires modifications to the existing designs of olfactometers. To create a testing apparatus in which there is no chemical memory to confound tests, we detail the technical aspects of a new tool with design influences from other olfactometry tools. In addition, this new tool was used to evaluate a novel formulation of metofluthrin for use as an outdoor residual treatment. After sourcing materials to prioritize glass and metal construction, a modular wind tunnel was developed that hybridizes wind tunnel and olfactometer specifications. Volatile contaminants were removed by strong ultraviolet light within the chamber before and between trials. Repellent trials were conducted with an experimental formulation of metofluthrin and a commercial formulation of esfenvalerate, prallethrin, and piperonyl butoxide (Onslaught Fast Cap) against Aedes albopictus (Skuse). Toxicant vapors were delivered with attractants from a lure with behavioral responses scored 20 min post-exposure. Upwind attraction to the attractant lure and the Onslaught Fast Cap plus lure resulted in 90 and 75% capture, respectively. In contrast, metofluthrin vapors resulted in less than 10% attraction, while also causing repellency, disorientation, knockdown, and mortality effects. Our findings demonstrated that an inert modular wind tunnel was functional for mitigating toxic secondary exposures of spatial repellents amidst complex behavioral analysis in mosquitoes. The resulting observations with formulated metofluthrin positively reinforce the merit of transitioning metofluthrin into expanded roles in mosquito management.

Rhodnius prolixus (Stål, 1859) is the major vector of Trypanosoma cruzi in Colombia and Venezuela. The species is strongly associated with high-altitude ecotopes, such as sylvatic palms (Attalea butyracea), where spatially and temporally stable infestations are established. We investigated temporal variation in regards to the presence of R. prolixus in rural dwellings in the department of Casanare (eastern Colombia) over a period of 12 mo. Thirty houses were sampled from January to December 2017 by installing Maria sensors, collecting triatomines through community entomological surveillance, and conducting a monthly search in each house. The collection of specimens from the houses varied significantly by month with the higher number of collections occurring in the low-rainfall season and the lower number of collections occurring in the months of increased precipitation. The proportions of males, females, and nymphs also varied significantly throughout the time period: nymphs (fifth instar only) were reported only during May, July, and September and significantly greater numbers of females than males were reported in the inspected dwellings in all months. Density, crowding, and colonization indices varied according to the season. A bloodmeal analysis revealed 17 different hosts. A total of 42 randomly selected R. prolixus specimens were subjected to molecular analyses for detection of T. cruzi DNA with 22 found positive (infection prevalence of 52%). In conclusion, we observed a high presence of R. prolixus (infected with T. cruzi) in dwellings close to native palm plantations. These findings indicate a high risk of vector transmission of T. cruzi for people in the study areas and challenges for the current vector control schemes in the region.

Musca domestica L., 1758, is an important mechanical vector of several pathogens for humans and livestock, making it essential to study new alternatives of more efficient and safer control for this dipteran. This study evaluated the toxicity of the phenylpropanoids eugenol and (E)-cinnamaldehyde on its life stages. A contact test with 10 repetitions (n = 10) was performed for each substance concentration on each post-embryonic immature life stage. Both substances presented insecticidal activity on the immature life stages of the dipteran, and secondary effects on development caused by sublethal concentrations. Larvicidal activity was shown from the 1.25 mg/ml concentration by eugenol and from 2.5 mg/ml by (E)-cinnamaldehyde, and both substances had a 100% larval treatment efficacy (LTE) from the 5mg/ml concentration. For pupal treatment, (E)-cinnamaldehyde differed from the control from the 10 mg/ml concentration (P < 0.05), and both phenylpropanoids caused malformation in adults from 10 mg/ml. The highest pupal treatment efficacy (PTE) was obtained from the 30 mg/ml concentration, 67.2% for (E)-cinnamaldehyde, and 32% for eugenol. The products tested in this study showed high larvicidal potential, and both presented pupicidal effects and caused malformation in adults from treated pupae.

Common bed bug Cimex lectularius (L.) (Hemiptera: Cimicidae) infestations are on the rise and due to the development of pesticide resistance they are becoming more difficult to control, affordably. We evaluated a naturally occurring compound methyl benzoate (MB) and related analogs, previously reported to have insecticidal activity on several agricultural pests, for its fumigant action on the common bed bug, C. lectularius L. A discriminating concentration was used to determine the effectiveness of MB, and several of its analogs as fumigants in a laboratory assay. It was found that MB provided >90% control of adult bed bugs in this laboratory fumigant assay. LC₅₀ values were calculated for MB against both a pyrethroid-susceptible and a pyrethroid-resistant strain of common bed bugs. It was determined that both strains were susceptible in this laboratory assay. However, when MB was tested in a field-like assay and compared to a commercially available bed bug control product, it was found to be significantly less effective compared to the commercial product. Our study has found that while MB has the potential to be used as a bed bug control agent, refinements in the delivery system will be needed to increase efficacy under field-like conditions.

Excito-repellency activity of plant extracts have been increasingly studied as mosquito repellents. In this study, the crude extract of Andrographis paniculata was evaluated for its noncontact repellency, contact excitation (irritancy + repellency), and knockdown/toxicity response against five colonized mosquitoes; Aedes aegypti (L.), Aedes albopictus (Skuse), Anopheles dirus Peyton & Harrison, Anopheles epiroticus Linton & Harbach, and Culex quinquefasciatus Say (Diptera: Culicidae) using an excito-repellency assay system under laboratory-controlled conditions. The escape responses were observed at four different concentrations (0.5–5.0% w/v) with A. paniculata showing strong spatial repellency against Ae. albopictus (96.7% escape) and Ae. aegypti (71.7% escape) at the 2.5% and 0.5% concentrations, respectively. At 0.5% and 5.0% concentrations, the greatest repellency was seen for An. dirus (48.2% escape) and Cx. quinquefasciatus (59.7% escape), respectively. Comparatively, low repellency action was observed against An. epiroticus (1.6–15.0% escape). Escape in contact assays (before adjustment) was generally less pronounced compared to noncontact spatial repellency, with Ae. albopictus showing highest percent escape (71.4% escape) in the contact assay at 1.0% concentration. After adjusting for spatial repellency, escape due to contact irritancy alone was either not present or an insignificant contribution to the overall avoidance response for all species. No knockdown or mortality at 24-h postexposure was observed in any trials.These findings indicate that the A. paniculata crude extract is more active against day-biting mosquitoes; however, this may be a reflection of the time of testing.This study demonstrates compelling evidence that A. paniculata extract performs primarily as a spatial repellent. Further investigations exploring the use A. paniculata as a potential active ingredient in repellent products are needed.

Culex quinquefasciatus Say is an important pest species and a vector of multiple pathogens. Insecticide applications are necessary for the effective control of mosquitoes. In the current study, a laboratory population of Cx. quinquefasciatus was exposed to chlorpyrifos for 15 consecutive generations and then assessed for the changes in detoxification enzyme activities before and after exposure to Metarhizium anisopliae (Metschn.) Sorokin and Beauveria bassiana (Bals.) Vuill. during 14th–15th generations. Activities of acetylcholinesterase (AChE), glutathione S-transferase (GST), esterase (EST), acid phosphatases (ACP), and alkaline phosphatases (ALP) were increased in the chlorpyrifos-selected (Chlor-SEL) population in relation to an unselected (Un-SEL) population. The resistance ratio of Chlor-SEL 15th generation (G₁₅) was increased 3,583-fold against first generation (G₁) and 6,026-fold against the Un-SEL population. The results depicted maximum activities of ACP (83.48), ALP (65.54), GST (13.047), EST (10.42), and AChE (4.86) µmol/min of mg/ml protein at G₁₅ after consecutive chlorpyrifos applications. The Chlor-SEL populations at G₁₄–G₁₅ were treated with different concentrations of M. anisopliae and B. bassiana for possible suppression of enzymatic activities. Activities of ACP were suppressed to 24.22 µmol/min of mg/ml protein at G₁₅ when exposed to B. bassiana and 22.40 µmol/min of mg/ml protein at G₁₄ after exposure to M. anisopliae. The suppression of detoxification enzymes by application of fungi in resistant population of Cx. quinquefasciatus will aid in the mosquito's management programs.

Phlebotomine sand flies (Diptera: Psychodidae) are the vectors of human and canine leishmaniasis, sand fly fever, and other arboviruses and bacteria. The control of sand flies is recommended by World Health Organization throughout the world. In this study, we investigated the susceptibility of field-collected sand flies against thiamethoxam inTurkey. The adult sand flies collected were from five different locations in three provinces;Yeşilöz and Büyükpınar districts in Antalya province, Develi district in Kayseri province, and Üçpınar and Bayındırlık districts in Manisa province. They were investigated using two different doses (0.125 and 0.25 g ai/m²) of thiamethoxam under laboratory conditions. After 1-h exposure, all sand flies were found highly susceptible to thiamethoxam and both test doses caused 100% mortality after 24 h. Considering the KDT₅₀ time, flies collected fromYeşilöz district in Antalya province were found to be most sensitive and flies collected from Üçpınar district in Manisa province were found as the most resistance to thiamethoxam. The results show that Turkish sand flies were highly susceptible to thiamethoxam and it can be used for the control of sand flies in the field.

Aedes aegypti (L.) is the primary vector of the viruses that cause dengue, Zika, and chikungunya, for which effective vaccines and drugs are still lacking. Current strategies for suppressing arbovirus outbreaks based on insecticide use pose a challenge because of the rapid increase in resistance. The widespread and excessive use of pyrethroid-based insecticides has created a large selection pressure for a kdr-type resistance, caused by mutations in the para gene of the voltage-gated sodium channel (vgsc). Our objective was to evaluate the allelic frequency of natural populations of Ae. aegypti of Mexico at codon 410 of the para gene.Twenty-six Ae. aegypti populations from east and southern Mexico were genotyped for the codon 410 using allele-specific PCR.The frequencies of the L410 allele in Ae. aegypti ranged from 0.10 to 0.99; however, most of the frequencies were in the range of 0.36 to 0.64.The highest frequencies were found in three populations from the state of Veracruz, namely, Minatitlan with 0.99, Poza Rica with 0.82, and Jose Cardel with 0.97, along with populations from Cancun in Quintana Roo with 0.93, Frontera inTabasco with 0.91, and Ciudad del Carmen in Campeche with 0.86. The frequency of the L410 allele was high in all populations of Ae. aegypti with higher values in populations of the southeast of the country.The knowledge of specific substitutions in vgsc and their interaction to confer resistance is essential to predict and develop future strategies for resistance management in Ae. aegypti in Mexico.

Aedes albopictus (Skuse) is an important invasive species and vector of several important arboviruses across the globe. This species uses small water-holding cryptic containers as egg laying sites, which pose serious challenges to effective control of adult mosquito populations. Herein, we examined the response of gravid female Ae. albopictus to various features of common downspout extension tubes associated with human dwellings and the effectiveness of control efforts to eliminate larvae. Controlled field trials quantified oviposition in 1) extensions versus rubber bowls meant to mimic other container types, 2) among different shapes and materials of extensions, and 3) among different colors of extensions. We also investigated how flushing and use of Bti larvicides could control larvae. Females were more likely to lay eggs in flat plastic or metal extensions compared to rubber bowls. Eggs were also more plentiful in flat plastic extensions versus either corrugated or metal, and dark brown corrugated extensions had more eggs compared to tan or white. Flushing reduced nearly all larvae when the extensions were properly angled, and applications of Bti pellets or dunks were effective at killing most larvae. We show that dark extensions were preferred over other colors, and that larvae can be effectively removed with minimal effort. However, effective control will likely only come from better education of the public about proper installation of extensions.

Aedes mosquitoes are vectors of several emerging diseases and are spreading worldwide. We investigated the spatiotemporal dynamics of Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse) mosquito trap captures in Brownsville, TX, using high-resolution land cover, socioeconomic, and meteorological data. We modeled mosquito trap counts using a Bayesian hierarchical mixed-effects model with spatially correlated residuals. The models indicated an inverse relationship between temperature and mosquito trap counts for both species, which may be due to the hot and arid climate of southern Texas. The temporal trend in mosquito populations indicated Ae. aegypti populations peaking in the late spring and Ae. albopictus reaching a maximum in winter. Our results indicated that seasonal weather variation, vegetation height, human population, and land cover determine which of the two Aedes species will predominate.

Flood frequency is expected to increase across the globe with climate change. Understanding the relationship between flooding and arboviral disease can reduce disease risk and associated costs. South-eastern Australia is dominated by the flood-prone Murray-Darling River system where the incidence of Australia's most common arboviral disease, Ross River virus (RRV), is high. This study aimed to determine the relationship between riverine flooding and RRV disease outbreaks in inland south-eastern Australia, specifically New South Wales (NSW). Each study month from 1991 to 2013, for each of 37 local government areas (LGAs) was assigned ‘outbreak/non-outbreak' status based on long-term trimmed-average age-standardized RRV notification rates and ‘flood/non-flood’ status based on riverine overflow. LGAs were grouped into eight climate zones with the relationship between flood and RRV outbreak modeled using generalized estimating equations. Modeling adjusted for rainfall in the previous 1–3 mo. Spring–summer flooding increased the odds of summer RRV outbreaks in three climate zones before and after adjusting for rainfall 1, 2, and 3 mo prior to the outbreak. Flooding at any time of the year was not predictive of RRV outbreaks in the remaining five climate zones. Predicting RRV disease outbreaks with flood events can assist with more targeted mosquito spraying programs, thereby reducing disease transmission and mosquito resistance.

Laboratory rearing procedures of Culicoides stellifer Coquillett (Diptera: Ceratopogonidae) were evaluated with an aim towards colonization of this species. Eggs collected from field-collected gravid females were placed on 0.25% agar slants and given a diet of 1) nematodes (Panagrellus redivivus Linnaeus), 2) nematodes + lactalbumin and yeast (LY), 3) microbes from nematode medium, and 4) tap water (autoclaved). Complete larval development to adult stage occurred only in two treatments: 1) nematodes and 2) nematodes + LY. Culicoides stellifer larvae could not survive beyond 1 wk on a diet of microbes alone or in the sterile water treatment. Larval survival rates were high using nematode diet (79.2 ± 11.3% [mean ± SE]) but were slightly lower in the nematode + LY group (66.5 ± 19.6%). Larval stage lasted ∼21 d in both treatments. Sex ratio of F1 adults was ∼1:1 (M:F) using nematode diet but was male biased (∼2:1) with nematode + LY diet. These findings collectively suggest that a microbial community is required for midge larvae, either to support invertebrate prey base or as a potential food source. But in the present study, the supplied microbes alone were not sufficient to support midge survival/development. It appears that other nutritional components may also be essential to support the larval survival/development of C. stellifer. Overall, a simple diet of bacterial feeding nematodes and their associated microorganisms can be used to rear C. stellifer larvae under laboratory conditions. However, captive mating in F1 adults poses a major obstacle for successful colonization of this species currently.

Stable fly collections were conducted to study the species composition and daytime activity of Stomoxys spp. (Diptera: Muscidae) in Peninsular Thailand (Songkhla, Trang, Pattalung, Nakon SiThammarat, and Satun provinces). Vavoua traps were used for fly collections in wet and dry seasons each year. Four Stomoxys species were found, S. calcitrans (L.) (Diptera: Muscidae) being the most common with 2,512 specimens (87.43% of captures), followed by S. indicus (Picard) (Diptera: Muscidae) with 306 specimens (10.65%), S. sitiens (Rondani) (Diptera: Muscidae) with 44 specimens (1.53%), and S. uruma (Shinonaga and Kano) (Diptera: Muscidae) with 11 specimens (0.39%). Subsequently, Songkhla Province was further selected to be a potential collection site to conduct a 1-yr abundance study, due to mixed crop-livestock farming in one place. Stomoxys calcitrans was predominant from 0800 to 1000 h with 4,921 specimens (93.6%) while S. indicus with 317 specimens (6%) and S. sitiens with 19 specimens (0.4%) were numerically dominant from 0600 to 0800 and 1600 to 1800 h. A proportion of male and female of each species was also established. This overall finding could be used as an ideal for nationwide species distribution status for the guidance of appropriate fly control. This information can lighten the way for the future control measures program activity of stable flies in Thailand.

The study aims to make an update on the distribution and ecology of sand flies in the Quang Ninh province, Northern Vietnam, where Leishmania cases were reported in 2001. Seventeen sites were chosen in three districts of the province: Ha Long, Cam Pha, and Hoanh Bo. Phlebotomine sand flies were collected using 68 CDC light traps from May 30 to 3 June 2016. Captured specimens were transferred individually into Eppendorf tubes with 90% ethanol.The sand fly heads and genitalia were removed and were mounted in Euparal after successive different baths. Specimen identification was determined based on the morphology of the cibarium, pharynx, and/or male genitalia or female spermathecae. A total of 416 sand flies (125 females, 283 males) belonging to four genera were collected and 10 sand fly species were identified: Sergentomyia silvatica, Se. barraudi, Se. hivernus, Se. bailyi, Phlebotomus mascomai, Ph. stantoni, Ph. yunshengensis, Ph. betisi, Chinius junlianensis, Idiophlebotomus longiforceps.The Sergentomyia genus prevailed (79.7% of the collected sand flies), followed by the Phlebotomus genus (13.7%), the Chinius genus (6.1%), and the Idiophlebotomus genus (0.8%). Besides these well-defined taxa, five specimens, named sp1, showed unknown morphological characteristics, requiring further study.The majority of sand flies were collected in rock caves suggesting the cavernicolous character of the species in the Quang Ninh province. However, specimens were also collected in intra and peridomiciliary sites in which Ph. stantoni and Se. hivernus were found as the main species. It is worth noting that two Ph. stantoni were found in the house of a patient affected by Leishmania.

The use of insect markers, such as fluorescent powders, is a useful tool for studying ecological and epidemiological questions. Evaluating their effect on vectors of human disease agents, such as the invasive mosquito vector Aedes aegypti (Linnaeus), is crucial for their practical and reliable use, especially in parameters linked to the risk of disease transmission such as adult survival, dispersal, and host-seeking. Seven fluorescent powders (Hercules Radiant, DayGlo (DG), Risk Reactor (RR), and Angstrom Technologies), applied externally on cohorts of Ae. aegypti female mosquitoes, were tested to determine their impact on survival and recapture by baited mosquito traps, and their detectability after being exposed to controlled laboratory and semifield environments. There were no significant differences in survival among marked and unmarked females across all powders. Marked females were significantly less likely to be captured in baited traps relative to unmarked females, except for one of the DG powders. All females remained visibly marked on five parts of their body for 30 d (under both environments), except for one of the RR powders. The tested powders and application method are suitable for tracking mosquitoes throughout most of their lives under different environments, without significantly affecting their survival, but with potential impact on recapture by baited traps, possibly due to effects on senses or other physiological traits.

Lyme disease is the most commonly reported vector-borne illness and sixth most commonly reported notifiable infectious disease in the United States. The majority of cases occur in the Northeast and upper-Midwest, and the number and geographic distribution of cases is steadily increasing. The blacklegged tick (Ixodes scapularis Say) is the principal vector of the Lyme disease spirochete (Borrelia burgdorferi sensu stricto) in eastern North America. Although Lyme disease risk has been studied in residential and recreational settings across rural to urban landscapes including metropolitan areas, risk within U.S. cities has not been adequately evaluated despite the presence of natural and undeveloped public parkland where visitors could be exposed to B. burgdorferi-infected I. scapularis. We studied the occurrence of I. scapularis and infection prevalence of B. burgdorferi in four insular regional parks within the city of Pittsburgh to assess Lyme disease risk of exposure to infected adults and nymphs. We found that the density of I. scapularis adults (1.16 ± 0.21 ticks/100 m²) and nymphs (3.42 ± 0.45 ticks/100 m²), infection prevalence of B. burgdorferi in adults (51.9%) and nymphs (19.3%), and density of infected adults (0.60 ticks/100 m²) and nymphs (0.66 ticks/100 m²) are as high in these city parks as nonurban residential and recreational areas in the highly endemic coastal Northeast. These findings emphasize the need to reconsider, assess, and manage Lyme disease risk in greenspaces within cities, especially in high Lyme disease incidence states.

In urban ecotourism parks, the life cycle of American cutaneous leishmaniasis (ACL) agents can remain established, where phlebotomines may comprise potential risks for visitors. The present study aimed to survey the phlebotomine fauna of a forest park ‘Bosque Rodriques Alves-Jardim Botânico da Amazônia’ (BRAJBA), in the urban area of Belém, Brazil. The park was monthly surveyed in 2018 using CDC light traps placed in ground and canopy strata. Leishmania spp. isolated from dissected females were characterized by polymerase chain reaction-restriction fragment length polymorphism analysis (PCR-RFLP) analysis. Fluctuations in specimen capture were correlated with rainfall. Nyssomyia antunesi (Coutinho, 1939) was predominant for all surveyed ecotopes and capture methods in both areas. Females of Ny. antunesi resting on tree bases were observed attempting to bite researchers during early morning. One Bichromomyia flaviscutellata (Mangabeira, 1942) and one Trichophoromyia brachipyga (Mangabeira, 1942) were found naturally infected by flagellates. Only the strain from Th. brachipyga was isolated and characterized as Leishmania (Viannia) lainsoni Silveira, Shaw, Braga and Ishikawa, 1987. Monthly fluctuations of the three most abundant species, Ny. antunesi, Trichophoromyia ubiquitalis (Mangabeira, 1942) and Th. brachypiga, had statistically significant negative correlations with rainfall. The present study provided further information to better understand ACL ecology in the Belém urban area, where the urban parks surveyed appeared to offer potential risk of contracting the disease, thus requiring environmental management. These observations highlighted the need for including Ny. antunesi, Bi. flaviscutellata, Th. ubiquitalis, and Th. brachypiga in the priority list for continuous entomological surveillance.

First introduced into the United States in 1999,West Nile virus (WNV) has become endemic and has established itself as the predominant mosquito-borne arbovirus in North America. Transmitted by mosquitoes of the genus Culex, regional landscapes influence local vector species abundance, creating different mosquito ecologies that drive local transmission dynamics. In central Iowa, two mosquito species, Culex restuansTheobald and Culex pipiens Linnaeus, serve as the predominant mosquito vectors. Importantly, these mosquito populations are influenced by seasonal patterns in their abundance, with Cx. restuans preferring cool, early spring temperatures, while Cx. pipiens prefer the warmer, mid- to late-summer months. The point of the season at which Cx. pipiens becomes the dominant species is generally referred to as a ‘crossover’ period. To better understand the influence of crossover dynamics on WNV transmission, we examined environmental and mosquito abundance data, as well as mosquito infection rates and human disease cases from 2016 to 2018. We demonstrate that temperature influences the timing and duration of the crossover period, influencing mosquito abundance and human disease transmission. Together, these results suggest that Culex species crossover is an important variable of WNV transmission dynamics, which may provide an early warning indicators of increased WNV transmission.

Leptoglossus occidentalis (Heidemann) is an invasive species introduced in Europe, Asia, and most recently South America. In the present study, we report the overreaction situation caused by this bug in Chile, as it has been confused with kissing bugs (Reduviidae: Triatominae), Chagas' disease vectors. During 2018 and first months of 2019, we received 74 alleged cases of kissing bugs to confirm identification. From these, a total of 63 were identified as L. occidentalis, representing a 85% of the total denounces. Additionally, the first bite case in a human is described.The situation caused by L. occidentalis in Chile is discussed, and an illustrated table is provided to correctly identify this species and tell it apart fromTriatomines. It is concluded that L. occidentalis is well established in Chile, and it is necessary to educate the population on recognition of the bug and to avoid overreaction as the species can inflict painful bites, but not transmit any disease.

The blacklegged tick, Ixodes scapularis Say, is the primary Lyme disease vector in the eastern United States. Both immature stages of I. scapularis take blood meals from mice belonging to the genus Peromyscus. Mice are active during the night and spend the majority of diel periods in nests. Thus, immature I. scapularis have a greater opportunity to drop from Peromyscus hosts while in nests compared with the forest floor. Here, we collected 11 Peromyscus nests during a 3-mo period during which the immature I. scapularis are known to be active. We then examined nesting materials for the presence of I. scapularis. Immature I. scapularis were detected in 64% of Peromyscus nests examined. Additionally, 55% of the nests contained at least one Dermacentor variabilis Say larva. Eighty-seven percent of all larval ticks found within nests were blood-fed. Because Peromyscus spp. are highly competent reservoirs of numerous tick-borne pathogens, the ticks that detach in their nests may be important for the maintenance of tick-borne diseases. However, further studies are needed to determine the fate of the I. scapularis that detach in Peromyscus nests.

The bacterium Rickettsia rickettsii is the agent of Brazilian spotted fever (BSF), a highly fatal disease that is transmitted in Brazil mainly by the tick Amblyomma sculptum Berlese, which uses capybaras (Hydrochoerus hydrochaeris Linnaeus) as major hosts. In 2015, we captured nine capybaras in a BSF-endemic area of southeastern Brazil. From each capybara, we collected blood sera that were tested through the immunofluorescence assay using Rickettsia spp. antigens, and A. sculptum ticks, processed for isolation of R. rickettsii through guinea pig inoculation. All capybaras (100%) were seroreactive to Rickettsia spp., with highest titers to R. rickettsii. A total of 166 A. sculptum ticks were macerated and inoculated into nine guinea pigs, from which only one presented high fever and seroconverted to R. rickettsii. Blood from this febrile animal was inoculated into additional guinea pigs (guinea pig passages), which also became febrile and seroconverted, or when euthanized during the fever period, their internal organs (spleen, lung) were shown to contain R. rickettsii DNA. The present rickettsial isolate has been maintained cryopreserved as infected guinea pig organs. There was at least one R. rickettsii-infected tick among the 166 macerated ticks, giving a minimal infection rate of 0.6% (1/166). This infection rate is within the range of previous studies, which reported that only 0.05% to at most 1.28% A. sculptum ticks were infected by R. rickettsii in other BSF-endemic areas. These low infection rates support the low incidence of BSF, despite of A. sculptum being the most frequent human-biting tick in southeastern Brazil.

Hydroelectric power stations may affect the population dynamics of mosquitoes and sand flies, a group with impact on public health due to the possibility to transmit pathogens to humans. This work characterized and compared the fauna of mosquitoes and sand flies in a hydroelectric power station and peridomicile areas in the State of Minas Gerais, Brazil. Insect collections were performed in August 2015 at dry season and February 2016 in rainy season. Ten HP light traps were set at each of two sites for three consecutive days in each of two seasons (dry and rainy). Furthermore, collections with Shannon traps were made in each sampling area (hydropower plant and peridomicile area) from 4:00 p.m. being shut down at 8:00 p.m. for two consecutive days in each of two seasons (dry and rainy). In total, 1,222 insects from 13 genera and 27 species were collected. The most plentiful species were respectively Culex declarator (Dyar and Knab, 1906) and Pintomyia pessoai (Coutinho & Barretto, 1940). A high number of insects (78.5%) were collected during the rainy period (P < 0.05). About equitability, statistical significance was observed in the peridomicile area (dry season J = 0.75 and rainy season J = 0.82). The highest values of species diversity were observed in the hydropower plant (H = 2.68) and peridomicile area (H = 2.38) both in the rainy season with statistical significance comparing with dry season. Our results demonstrate that the occurrence of vector species in this region increases the potential risk of transmission of pathogens, especially arbovirus and Leishmania Ross, 1903.

Fleas are ectoparasites of various animals, including Homo sapiens Linnaeus, 1758 (Primates: Hominidae). Among the species relevant to the human health field, either due to their dermatopathological potential or because of their role as vectors of microorganisms responsible for infectious diseases, such as plague or murine typhus, are the human flea, oriental rat flea, closely related cat and dog fleas, and chigoe flea. However, other species can accidentally infest humans. We have herein reported two unusual cases of humans infested and bitten by Archaeopsylla erinacei, the hedgehog flea. This species has been identified using stereomicroscopy, on the base of key characteristics. Furthermore, a brief literature review has revealed that hedgehog fleas could carry human-infectious agents, such as Rickettsia felis Bouyer et al. 2001 (Rickettsiales: Rickettsiaceae) or Bartonella henselae Regnery et al.1992 (Rhizobia les: Bartonellaceae). Using molecular biology, we thus tested nine A. erinacei specimens taken from these patients, for several bacteria species commonly associated with hematophagous arthropods, implicated in human pathology. However, all our samples were proven negative. The role of A. erinacei in human epidemiology has never been evaluated to date. This report sought to remind us that these fleas can be accidental parasites in humans. In addition, recent findings pertaining to bacteria of medical interest that are present in these insects should be brought to the fore, given that the question of their role as vectors in human infections remains unanswered and deserves further investigation.

This study reports the third collection of Triatoma nitida Usinger in Mexico, with a brief description of the collection area and an investigation of parameters related to its vectorial capacity. Whether a triatomine (Hemiptera: Reduviidae) species is a primary or secondary vector is determined by factors that include vectorial capacity, anthropophilic habits, geographic distribution, and capacity to invade and colonize human dwellings. However, when the primary vectors are removed, secondary vectors, such as T. nitida, can become important transmitters of Trypanosoma cruzi Chagas to humans.To estimate the vectorial capacity of T. nitida, the egg-to-adult development time, number of blood meals required to molt to the adult stage, accumulative mortality, onset time for feeding, and feeding and defecation times were examined. Triatoma nitida (n = 100) required a median of 590 d to complete its development time, with a median of 31 blood meals. Almost half (46.5%) of the nymphs died during the cycle.The onset of feeding time exceeded 5 min in all nymphal instars (except on fourth-instar) and adults and feeding times exceeded 22 min in all instars, except on first-instar nymphs. No defecation was observed for 65.6% (n = 383) of the triatomines during a 30-min observation period. Based on the six parameters, the vectorial capacity of T. nitida should be considered as low. However, surveillance programs should include this species because the potential importance of T. nitida as a vector has been demonstrated in other countries.

Insect age estimates can be useful for estimating the postmortem interval when certain assumptions are met. Such estimates are based on species-specific development data that are temperature-dependent and variable, and therefore prone to different degrees of error depending on the combination of data sets, calculations, and assumptions applied in a specific instance. Because of this potential error, validating the methods employed is necessary for determining accuracy and precision of a given technique. For forensic entomology, validation of development data sets is one approach for identifying the uncertainty associated with insect age estimates. Cochliomyia macellaria (Fabricius) is a primary colonizer of remains across the United States and is commonly encountered in forensic investigations. A development study for this species was produced for a centralTexas, U.S. population; the variation associated with this data set and the pre-appearance interval were previously explored in an ecological model.The objectives of this study were to determine the accuracy of the development data and the validity of the ecological model when applied to immatures of known age developing under field conditions. Results indicate this data set is an accurate predictor of insect age when using development stage, supporting the validity of the ecological model in centralTexas. Age predictions made with all stages present in a sample were more accurate than predictions made with the most developed stage in a sample, and estimates of age when using the prepupal stage were overestimated regardless of prediction method, though thermal requirements for total development were similar.

Climate change is an important factor affecting the dynamics of the vectors population and, hence, the risk of vector-borne diseases. This study aimed to predict the environmental suitability for malaria vectors in Iran under climate change scenarios in 2030s and 2050s. Literature search was performed to find documents on the spatial distribution of Anopheles stephensi Liston, 1901, Anopheles culicifacies s.l. Giles, 1901, Anopheles fluviatilis s.l. James, 1902, Anopheles superpictus s.l. Grassi, 1899, Anopheles dthali Patton, 1905, Anopheles maculipennis s.l. Meigen, 1818, and Anopheles sacharovi Favre, 1903 (Diptera: Culicidae) published between 1970 and 2017. The bioclimatic data under three climate change scenarios (representative concentration pathway 2.6 [RCP2.6], RCP4.5, and RCP8.5) and MaxEnt model were used to predict the ecological niches for each species. Comparison between the two study periods under the three scenarios for each species revealed that RCP8.5 would reduce the area at risk for An. culicifacies s.l., An. dthali and An. superpictus s.l. in the 2050s compared to the 2030s, but the reverse will be induced by RCP2.6 and RCP4.5 scenarios. For An. fluviatilis s.l., RCP2.6 will reduce the risk areas in the 2050s, whereas an increase is expected under the two other scenarios. Moreover, all scenarios would decrease the high-risk areas of An. maculipennis s.l. in the 2050s. For An. sacharovi, RCP2.6 would increase its high-risk areas, whereas RCP4.5 and RCP8.5 would decrease its exposure. The high-risk area of An. stephensi is expected to increase under RCP8.5 in the 2030s and RCP4.5 in 2050s, but it will be almost unchanged or reduced under other scenarios.

Sarcophaga peregrina is an important flesh fly species for estimating the minimum postmortem interval (PMI_min) in forensic entomology. The accurate determination of the developmental age is a crucial task for using necrophagous sarcophagids to estimate PMI_min. During larval development, the age determination is straight forward by the morphological changes and variation of length, weight, and width; however, the age estimation of sarcophagid intrapuparial is more difficult due to anatomical and morphological changes not being visible. The analysis of differentially expressed genes (DEGs) during sarcophagid metamorphosis is a potential method for age estimation of intrapuparial. In the present study, real-time quantitative polymerase chain reaction (RT-qPCR) was used to analyze the differential gene expression level of S. peregrina intrapuparial in different constant temperatures (35°C, 25°C, and 15°C). In addition, the appropriate reference genes of S. peregrina were selected in the intrapuparial and at different temperatures to obtain reliable and valid gene expression profiles. The results indicated that two candidate genes (18S rRNA and 28S rRNA) were the most reliable reference genes, and four DEGs (Hsp90, A-alpha, AFP, AFBP) have the potential to be used to more accuracy estimate the age of S. peregrina intrapuparial.

The area in and around Chicago, IL, is a hotspot of West Nile virus activity. The discovery of a Culex pipiens form molestus Forskӓl population in Chicago in 2009 added to speculation that offspring from hybridization between Cx. pipiens f. pipiens L. and f. molestus could show a preference for feeding on humans. We collected blood-fed female mosquitoes (N = 1,023) from eight residential sites and one public park site in Chicago in July and August 2012. Bloodmeal analysis using the COI (cytochrome c oxidase subunit I) gene was performed to ascertain host choice. Almost all (99%) bloodmeals came from birds, with American Robins (Turdus migratorius L.) and House Sparrows (Passer domesticus L.) making up the largest percentage (74% combined). A forage ratio analysis comparing bird species fed upon and available bird species based on point count surveys indicated Northern Cardinals (Cardinalis cardinalis) and American Robins (Turdus migratorius) appeared to be over-utilized, whereas several species were under-utilized. Two human bloodmeals came from Culex pipiens complex mosquitoes. Admixture and population genetic analyses were conducted with 15 microsatellite loci on head and thorax DNA from the collected blood-fed mosquitoes. A modest amount of hybridization was detected between Cx. pipiens f. pipiens and f. molestus, as well as between f. pipiens and Cx. quinquefasciatus Say. Several pure Cx. quinquefasciatus individuals were noted at the two Trumbull Park sites. Our data suggest that Cx. pipiens complex mosquitoes in the Chicago area are not highly introgressed with f. molestus and appear to utilize avian hosts.

Vector feeding behavior can have a profound influence on the transmission of vector-borne diseases. In the case of black-legged ticks, Ixodes scapularis Say, which vectors the agents of Lyme disease, babesiosis, and other pathogens, the timing and propensity of questing can determine which hosts are fed upon as well as the risk of contact with humans.Yet we know little about the controls and constraints on tick host-finding behavior under natural conditions.Ticks must balance the need to quest for blood meal hosts with the risk of desiccation, all on a fixed energy budget. Prior research, primarily in the laboratory, has shown that questing activity varies with conditions (e.g., temperature, relative humidity), light-dark cycles, and energy reserves, but the findings have been idiosyncratic and the dominant factor(s) in nature remains unknown. We measured questing activity of nymphs and larvae throughout the day and night and over several weeks in enclosures across a range of suitable tick habitats within a site in the Northeast. Activity of nymphs increased slightly during dawn and dusk, opposite of larvae, and declined slightly with air temperature and rain, but these patterns were weak and inconsistent among replicate sites. Rather it appears a fraction of ticks were questing most of the time, regardless of conditions. Our study suggests neither climatic conditions or light-dark cycles have appreciable influence on tick questing behavior.

A new flea (Insecta: Siphonaptera) species belonging to the Palaeopsylla minor-group, Palaeopsylla (Palaeopsylla) beaucournui n. sp. is described and illustrated. Specimens (14 males and seven females) of this new species were collected from Talpa levantisThomas (Mammalia:Talpidae) in the deciduous mixed forest in Bursa province of Marmara Region, Turkey.

Males of cryptic or closely related species present great morphological variation in their genitalia, whereas females, such as those of the Chagasi Series of the Psychodopygus Mangabeira, 1941 genus, are more similar. Therefore, our aim was to study the fine structure of the male genitalia of five species of the Chagasi Series to better understand the variation in their morphology and its influence on the copulatory process. The sand fly species were captured in the following Brazilian states: Psychodopygus chagasi (Costa Lima, 1941) (Rondônia), Psychodopygus complexus (Mangabeira, 1941) (Tocantins), Psychodopygus squamiventris maripaensis (Floch & Abonnenc, 1946) (Amapá), Psychodopygus squamiventris squamiventris (Lutz & Neiva, 1912) (Amazonas), and Psychodopygus wellcomei Fraiha, Shaw & Lainson, 1971 (Pará and Ceará). Insects were stored in ethanol 70% (then dehydrated) and dry after they were sputtered with gold. The samples were observed under a scanning electron microscope. Microtrichiae, two types of trichoid sensilla, coeloconic and chaetic sensillae, were observed on the antenna of all species, with no difference between them. Only on the anepimeron of P. squamiventris squamiventris a modified ‘racket'-like scale was observed. As for the male genitalia, the setae and structures of each species were fully described, such as the small setae on the paramere apex of the P. squamiventris subspecies, and the grooves present in this region and on the paramere lobe of P. complexus and P. wellcomei, which are impossible to observe with optic microscopy. New information is thus provided on the male genitalia, which can contribute to future bionomic studies of these species.