Bernard Greenberg was a ground-breaking scientist in the worlds of medical-veterinary and forensic entomology, studying the ability of flies to serve as a vector of human and other vertebrate pathogens. His work also extended beyond these topics, creating key studies on flies and their associated microbial ecology.These efforts led to numerous research publications and two books on flies and their associated microorganisms. Greenberg served a pioneering role in establishing the field of forensic entomology in the USA later in his career, publishing key papers and a book that are highly cited to this day. We present a review of Dr Greenberg's scientific contributions concerning flies and disease, insect/microbe interactions, and insects as forensic indicators.

Geographic ranges of ticks and tick-borne pathogens within North America are shifting due to environmental changes and human-driven activities, with species of public health concern presenting a multifaceted risk to human health. Innovative strategies and continued collaboration to control tick populations are needed to combat this growing threat. We conducted a scoping review of the literature to describe the nature of applied tick control research conducted in North America (Canada, Mexico, and the United States) to date, with the goal of describing key concepts and identifying gaps in this research area. A total of 244 articles met our inclusion criteria and were reviewed for patterns in applied tick control authorship and funding, study location, target species, and control methodology. Most studies (83.6%) were conducted exclusively in the United States and 75% focused on ticks of public health concern, principally Amblyomma americanum (Linnaeus, Acari: Ixodidae), Dermacentor variabilis (Say, Acari: Ixodidae), Ixodes scapularis Say (Acari: Ixodidae), and Rhipicephalus sanguineus (Latreille, Acari: Ixodidae).The majority of funding was provided through US federal agencies, predominantly the Centers for Disease Control and Prevention and the United States Department of Agriculture. Ixodes scapularis was the target of over 50% of identified articles, with the majority of research conducted within 3 states in the Northeast region of the U.S. Only 8.2% of included studies evaluated integrated tick management interventions. We note gaps in tick control research regarding (i) non-Ixodes medically relevant tick species, (ii) endemic range coverage, and (iii) control methodologies evaluated.

Mosquito control using pyrethrins and synthetic pyrethroids (PSP) is important for preventing vector-borne diseases. Although the benefits associated with PSP use are well-documented, public concern exists regarding potential human adverse health effects.The aim of this scoping review was to describe adverse human health effects associated with PSP use for community adult mosquito control. A literature search using the databases MEDLINE, EMBASE, Agricultural and Environmental Science Collection, CAB Abstracts, and Scopus obtained 6,154 original peer-reviewed articles published during 1 January 2000 to 22 May 2024. Articles were independently reviewed for inclusion using predetermined exclusion and inclusion criteria. Data were extracted from 10 included articles. Study designs included cohort (n = 5), cross-sectional (n = 2), and risk assessment (n = 4). One article included 2 study designs. Of the cohort studies, one was prospective and the remainder were retrospective. A causal relationship between PSP application for adult mosquito control and adverse human health impacts was not identified. No increases in acute health manifestations were reported.The 4 risk assessments estimated that PSP exposures were not above the regulatory level of concern; a meta-analysis determined the likelihood of PSP exposures exceeding the regulatory level of concern was <0.0001. The limited evidence indicated that PSP applied appropriately for control of nuisance mosquitoes or mosquitoes that transmit arboviruses do not pose acute or chronic human health risks. Continued investigation into potential human health impacts of PSP would help inform guidelines for adult mosquito control and help inform public health decision making.

In response to notable increases in tick-associated illnesses in the United States, recent public health policies encouraged multi-sector collaborative approaches to preventing vector-borne diseases. Primary prevention strategies focus on educating the public about risks for tick-borne diseases and encouraging adoption of personal protection strategies. Accurate descriptions of when and where people are at risk for tick-borne diseases aid in the optimization of prevention messaging.Tick and tick-borne pathogen data can be used to fill gaps in epidemiological surveillance. However, the utility of acarological data is limited by their completeness. National maps showing the distribution of medically important tick species and the pathogens they carry are often incomplete or non-existent. Recent policies encourage accelerated efforts to monitor changes in the distribution and abundance of medically important ticks and the presence and prevalence of human pathogens that they carry, and to provide actionable, evidence-based information to the public, health care providers and public health policy makers. In 2018, the Centers for Disease Control and Prevention initiated a national tick surveillance program focused on Ixodes ticks. The national program coordinated and expanded upon existing efforts led by public health departments and academic institutions. Here, we describe experiences of state public health departments engaged in Ixodes tick surveillance, including information on why they initiated Ixodes surveillance programs, programmatic objectives, and strategies for maintaining tick surveillance programs. We share experiences and challenges in interpreting or communicating tick surveillance data to stakeholders and explore how the acarological data are used to complement epidemiological data.

Little is known about the behaviors of African equatorial rain forest mosquito species and their potential role as sylvatic and bridge-vectors of various pathogens of animal and public health. In 2016 and 2017, the diversity and sources of water supporting immature development of mosquitoes inTalangaye Rainforest (South West Cameroon) before, during and after deforestation were investigated. Mosquito eggs, larvae and pupae were collected from 12 natural, seminatural, and artificial water sources and reared to adults. A total of 595 adult mosquitoes belonging to seven genera and at least 43 species were identified. Culex was the most abundant (56.3%) and was encountered in the majority in bamboo pots. Aedes and Uranotaenia species were mostly found in rock pools, while Anopheles and Hodgesia species solely prefer stream pools. In terms of mosquito abundance, rock pools were the most productive (29.91%) followed by bamboo pots (24.7%). Natural sites such as rock pools, tree holes, and stream pools recorded a greater number of species (S = 21, 14 and 12 respectively). During the rainy season, rock pools (46.23%) and bamboo pots (18.7%) were the most productive water bodies, while in the dry season, bamboo pots (35.71%) and stream pools (35.71%) harbored the most mosquitoes. The disturbed and pristine-like habitats had the greatest number of mosquitoes and breeding sites compared to palm plantation. This study provides some useful data on water sources used for immature development of forest mosquito species in Southwest Cameroon and how some species might adapt to changing landscapes, especially due to deforestation.

A comprehensive study was conducted on the life history parameters of an important vector Culicoides oxystoma Kieffer (Diptera: Ceratopogonidae), to standardize potential rearing procedures. Data on life history traits and rearing conditions are crucial for establishing laboratory colony and conducting vector competence-based studies utilizing specimens with a known rearing history. Six different substrate compositions were used to rear the larvae: S1: habitat mud containing cattle manure + nutrient broth + yeast, S2: yeast, S3: habitat mud containing cattle manure + nutrient broth, S4: nutrient broth, S5: sterile (habitat mud consisting cattle manure + nutrient broth + yeast) and S6: tap water. Gravid females preferred ovipositing on beds moistened with tap water compared to distilled water. Egg hatching recorded minimal (3%) in the sterile substrate (S5), hinting at the role of live microbial load. Progression of larval instars got disrupted at 1st instars in S5 and S6. Larval survival and adult emergence were the highest in S1 and the lowest in S4, indicating that S1 is highly effective in the rearing of this species.The life cycle parameters and duration between transitional stages were evaluated at 15 °C, 20 °C, 26 °C, 30 °C, and 35 °C using rearing substrate S1.The highest larval survival (>70%) and adult emergence (69%) were achieved at 26 °C.The duration from egg to adult was 16 to 20 d at 35 °C, 18 to 24 d at 26 °C, but up to 36 d at 15 °C. Elucidating the effective rearing conditionalities of this important vector species will be helpful to study the transmission cycles of pathogens.

Graphical Abstract

Developmental data for necrophagous Diptera are frequently used in medico-legal investigations to estimate portions of the postmortem interval and interpret periods of insect activity. These applications require baseline developmental data for local populations from geographic locations of interest. For the widely distributed blow fly Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae), detailed developmental data does not exist for many locations in the mid-Atlantic region of the United States.This study examined development of C. vicina collected from a large, metropolitan city (Baltimore) in Maryland utilizing 11 ambient temperatures.The developmental threshold and thermal range of growth and tolerance were also estimated, as well as critical thermal minima and maxima based on thermal injury. For this population, linear growth was observed between 10°C and 25°C, whereas flies failed to complete development at temperatures below 7°C or above 28°C. Growth at low temperatures was not curvilinear, which contrasts with other developmental studies using C. vicina and other calliphorids.The lower developmental threshold was estimated to be 5.9°C and corresponds closely with experimental observations.The implications of these result in reference to phenotypic plasticity in populations of C. vicina and applications in forensic entomology are discussed.

Iran is a biodiversity hotspot of scorpions with 80 recorded species. Thus, scorpion envenomation is a serious public health problem in the country. Here, we used habitat suitability modeling to assess the spatial distribution of scorpions in Iran. Only 45 species had sufficient georeferenced data. We used bioclimatic variables, soil temperature layers, and 9 modeling algorithms to perform habitat suitability modeling. We employed an ensemble approach to obtain the final models. We calculated the richness map and drew distribution maps for genera with more than 1 species. Also, we assessed the scorpions' species richness inside and outside of national parks. Finally, we created a risk map of encountering a venomous scorpion. The results showed that the highest scorpion richness is in the southern and southwestern parts of Iran, especially in the coastal areas of the Persian Gulf. We observed 3 biodiversity hotspots for scorpions that are located in the south and southwestern, central parts, and eastern parts of Iran. Except for northern parts, there is a possibility of encountering a venomous scorpion in other parts of Iran. The 3 biodiversity hotspots are also the areas with the highest chance of encountering a venomous species. We found that the hotspots are not protected and are located in areas facing land-use changes. Thus, hotspots have the highest human–scorpion conflicts. Our results provide new insight into the distribution of scorpion species in Iran. Conservation actions that ensure both human safety and species richness are essential and can be achieved by halting further land degradation in scorpion habitats and providing easy-to-understand manuals for local people.

Competition between mosquito species during the larval phase is a well-established mechanism structuring container mosquito communities, with invasive species often outperforming natives. We assessed the competitive outcome between 2 species that occur on the island of Puerto Rico, the historic invasive Aedes aegypti (L.) and the endemic Aedes mediovittatus (Coquillett) (Diptera: Culicidae). Trials were conducted under intra- and interspecific densities crossed with 2 amounts of 4 different leaf types serving as detrital resources for developing larvae; leaf types were representative of either urban or rural locations. Response variables included survival, male and female mass and development time, and a composite index of population growth (λ'). We also measured tannin levels in detrital environments, a secondary metabolite that can negatively influence mosquito development and survival. The co-occurrence of Ae. aegypti and Ae. mediovittatus generally did not affect survival or population growth of Ae. mediovittatus, however the converse was not true. Specifically, Ae. aegypti suffered lower survival and lower population growth in the presence of Ae. mediovittatus compared to when it was alone. Tannin concentrations did not correspond to competitive outcomes, as the highest tannin levels occurred under the detrital conditions where mosquitoes had highest growth and survival, with no evidence of differences between urban or rural leaf types. This is the first study to quantify the competitive outcomes between these species, both of which are part of the dengue transmission cycle on the island, and our findings suggest that Ae. mediovittatus is capable of outcompeting Ae. aegypti under some resource environments.

Comparative studies of the microbiota in whole-body mosquitoes from natural populations and laboratory-reared specimens are scarce, particularly in tropical countries like Colombia, where understanding microbial patterns is critical for effective disease control and vector management. This study examines the bacterial microbiota of Aedes aegypti by comparing field-collected mosquitoes from 3 Colombian regions (Southern Amazon, Central Andean region, and Northern Caribbean coast) with laboratory strains (Rockefeller, Otanche, andTolima).These regions are highly endemic for dengue and are associated with lineage 1 of Ae. aegypti, known for its elevated vector competence. Using next-generation sequencing of the 16S rRNA gene with Illumina technology, we found that field-collected mosquitoes exhibited significantly higher alpha and beta diversity compared to laboratory-reared specimens. Field mosquitoes were enriched with bacterial families such as Acetobacteraceae, Lactobacillaceae, and Bacillaceae, while laboratory mosquitoes showed a greater abundance of Enterobacteriaceae. Differential abundance analysis revealed that Acetobacter and Bacillus predominated in field mosquitoes, whereas Asaia, Cedacea, and Chryseobacterium were more common in laboratory specimens. Notably, Pseudomonas and Acinetobacter were consistently abundant across all samples. Our findings suggest that environmental factors, such as habitat and diet, significantly influence the bacterial composition and diversity of Ae. aegypti in Colombia. Future research should further explore how these factors, alongside genetic components, shape mosquito–micro-biota interactions and their implications for disease transmission and vector competence.

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Chagas disease is one of the most important vector-borne diseases in Mexico. Triatoma pallidipennis (Stål) is one of the most epidemiologically important vector species. Despite being classified as a single species, various studies (molecular, morphometric, and biological) on populations across its distribution suggested it is composed of a group of cryptic species.This study examined reproductive isolation among 5 populations of T. pallidipennis originating from the western, southern, and central regions of Mexico to help clarify the potential existence of a cryptic species complex of T. pallidipennis in Mexico. A generation of hybrids was analyzed for fertility and fecundity. Fertility rates varied from 50% to 100% in the parental crosses and from 20% to 100% in the F1 × F1 crosses. Fecundity ranged from 1.4 to 3.2 eggs/female/day in the parental crosses, which decreased to 0.9–2.9 in the F1 × F1 crosses (except in Jalisco × Morelos). The fertility of the eggs ranged from 61.4% to 85.4% in the parental crosses, dropping to 44% to 90.1% in some F1 × F1 crosses, indicating partial reproductive isolation among these populations.

Graphical Abstract

Malaria remains a major public health threat in Burkina Faso, as in most sub-Saharan Africa countries. Malaria control relies mainly on long-lasting insecticide-treated nets (LLINs) and indoor residual spraying. In Burkina Faso, an escalating of insecticide resistance has been observed over the last decades.This study aimed to investigate insecticide resistance and the underlying mechanisms in Anopheles gambiae complex in Ouagadougou. Anopheles gambiae s.l. larvae were collected from gutters and ponds, in Zogona,Tampouy andTanghin, 3 localities in Ouagadougou from July to October 2018.The larvae were reared in the laboratory to adults stage and susceptibility profile to pyrethroid, carbamate, and organophosphate insecticides was assessed using WHO tube assays. Mosquito species and mutations linked with insecticide resistance, were identified through PCR. More than 95% of the collected An. gambiae s.l. were An. arabiensis. An. arabiensis displayed high resistance to permethrin and deltamethrin, with mortalities below 30%, but was fully susceptible to bendiocarb, fenitrothion, and malathion. A high-frequency of the pyrethroid resistance-associated kdr mutation 1014F (0.81) was recorded, while the frequency of 1014S mutation (0.18) was lower. However, the carbamate and organophosphate-associated Ace-1 119S mutation was not detected. Localities and breeding site type appear to influence pyrethroid resistance in the An. arabiensis population of Ouagadougou. The high resistance to pyrethroids in An. arabiensis of urban Ouagadougou is underpinned, at least in part by high-frequency kdr mutations.This result supports the switch to next-generation LLINs, in well-established pyrethroid resistance zones of Burkina Faso including Ouagadougout

Aedes aegypti (Linnaeus) is the principal mosquito vector for many of the most medically significant arboviruses that threaten global public health. A better understanding of time-of-day variation in insecticide resistance mediated by detoxifying enzymes in Ae. aegypti could allow for targeted insecticide applications when susceptibility is highest and the upregulation of detoxification enzymes is lowest. Using a susceptible and metabolically resistant field Ae. aegypti strain from Florida, we investigated simulated photoperiodic changes in permethrin susceptibility and upregulation of detoxification enzymes by measuring permethrin LD₅₀ and expression of detoxification genes (GSTE7, GSTE2, CCEae3A, CYP9J28, and CYPBB2) for both strains every 4 h over a 24 h (12:12 h light: dark) cycle. We found that in both Ae. aegypti strains, permethrin susceptibility was lower during the day as compared to evening, with susceptibility lowest at dusk (18:00) and highest between 02:00 and 14:00. Although no significant changes in gene expression over time were observed in the susceptible Ae. aegypti strain, we documented increased expression of all investigated detoxification genes in the metabolically resistant field Ae. aegypti strain during the night (18:00 to 02:00) as compared to the day (06:00 to 14:00). These data suggest that permethrin applications made between midnight and dawn (06:00) may be more effective against Ae. aegypti as compared to applications made at dusk (approximately 18:00).

Pacific Coast tick fever is a recently described zoonotic disease in California caused by a spotted fever group rickettsia, Rickettsia rickettsii subsp. californica (formerly Rickettsia 364D) and transmitted by the Pacific Coast tick, Dermacentor occidentalis. Like many emerging vector-borne diseases, knowledge regarding the transmission cycle, contribution from potential amplifying hosts, and geographic distribution of R. rickettsii californica is limited. We paired molecular analysis with comparative spatial niche modeling to identify vertebrate hosts potentially involved in the transmission cycle of this pathogen. We identified R. rickettsii californica DNA in three mammal species (Otospermophilus beecheyi, Lepus californicus, and Sylvilagus audubonii). This is the first record of R. rickettsii californica detected in mammals and may indicate potential amplifying hosts for this human pathogen. Species niche modeling of uninfected and infected D. occidentalis identified areas of high suitability along the coast and Sierra Nevada foothills of California. These findings support the hypothesis that amplifying host(s) may support higher infection prevalence in the infected tick regions compared to other parts of the tick's range. Potential host species distribution models (SDMs) were constructed from museum records and niche overlap statistics were used to compare habitat suitability with R. rickettsii californica-infected tick SDMs. We found higher than null overlap of infected ticks with California ground squirrels (O. beecheyii) and trending, but nonsignificant, overlap with two lagomorph species. Pairing molecular and niche modeling may be a useful approach to identify species that are involved in the maintenance of emerging tick-borne zoonoses.

Black flies (Diptera: Simuliidae) are significant pests and vectors transmitting pathogens to humans and other animals. However, knowledge of species diversity as well as their role as pests and vectors in Laos is limited, despite the country having abundant suitable lotic habitats, that is, running water. In this study, we collected wild adult black fly specimens from Laos. Both morphology and genetic data supported that they were Simulium khelangense Takaoka, Srisuka and Saeung, and therefore, a new distribution record for this species. Screening of the blood protozoa from 106 females detected Leucocytozoon (n = 7) and Trypanosoma (n = 9). Identifications of Leucocytozoon based on cytochrome b sequences in MalAvi database indicated that 5 specimens had identical sequences to those of 4 lineages (GALLUS17 [n = 2], GALLUS35 [n = 1], GALLUS37 [n = 1], and GALLUS41 [n = 1]) of unidentified species (i.e., Leucocytozoon sp.).The remaining 2 had no identical sequences but were very similar (99%) to GALLUS34 and GALLUS41 lineages. Identifications of Trypanosoma based on the small subunit rRNA indicated that all were T. avium. The results presented here further support the role of S. khelangense as a potential vector of Leucocytozoon and Trypanosoma as well as being a possible pest of domestic avian species.

Host-seeking behavior of Culicoides species was examined from 2018 to 2019 in West Bengal, India, which elucidated diel activity, feeding success, attack rate, biting rate, and preferential landing of adult Culicoides on the cattle. A comparative assessment was done between the light trap and the aspirator.The host-seeking experiment involved a substantial timeframe of 297 h of catch collections over 27 nights.The number of adult Culicoides captured in the light trap was 1.3 times higher than the aspirator collections.The species in light trap catch were Culicoides oxystoma Kieffer Culicoides peregrinus Kieffer, and Culicoides fulvus Sen and Das Gupta (Diptera: Ceratopogonidae). However, only C. oxystoma and C. peregrinus were collected using the aspirator. The findings related to feeding success, attack rate, and biting rate carried significant implications for the vectorial potential of C. oxystoma and C. peregrinus.The light trap data suggest that Culicoides species displayed crepuscular behavior, while the aspirator collections peaked 1 h before sunrise, between 04:00 and 05:00 h, and gradually declined. A separate study evaluated the exophily and endophily of Culicoides in 2016 at Memari in West Bengal. To delve into the indoor–outdoor activity, 264 trap collections were made in 4 combinations: Light trap operated in the presence and absence of cattle, placed outdoors and indoors.The study revealed that the outdoor prevalence of midges was 14 times higher than the indoor.There was a 6-time increase in the prevalence of adult Culicoides in the presence of cattle, indicating a preference for outdoor locations for feeding.

Graphical Abstract

Filarial nematodes are parasitic roundworms transmitted by mosquitoes that can cause morbidity and mortality for their human and animal hosts.The filariae community, specifically infection prevalence of heartworm, Dirofilaria immitis (Filarioidea: Onchocercidae) (Leidy), and its primary mosquito vector species, has not been described in Connecticut since 1977. In light of the recent invasion and establishment of an important filariasis vector, Aedes albopictus (Diptera: Culicidae) (Skuse), we used molecular-based sequencing methods to identify filarial species infecting field-caught mosquitoes in Connecticut, United States.The filarial parasites identified include D. immitis, Aproctella sp., and Setaria sp. (Filarioidea: Setariidae).The total minimum infection rate for D. immitis for all mosquito species tested in 2020 was 0.97 [0.56 to 1.56] and in 2021 was 1.48 [0.93 to 2.24]. Aedes albopictus had the highest infection prevalence compared to other species during both years. We determined a low but persistent mosquito infection prevalence for D. immitis and suggest that Ae. albopictus is likely to be the primary vector in the region. Aproctella sp. and Setaria sp. had lower burdens compared to D. immitis. Persistent mosquito infection with filarial parasites, particularly in invasive species, poses a risk to veterinary and public health.

Mosquito-borne disease (MBD) incidence is increasing in the United States (U.S.), presenting an evolving health threat. Assessments of public perceptions have revealed limited awareness of MBDs among the U.S. population. Our team used focus groups to gain an in-depth understanding of risk perceptions regarding mosquito exposure and pesticide use, and benefit perceptions and motivators for bite prevention strategies. A total of 37 individuals participated in focus groups across 3 states: New Jersey (n = 14), NewYork (n = 15), and Massachusetts (n = 8). Most participants were unfamiliar with public mosquito control services and felt they were not at high exposure risk to any MBDs. Overall, participants were supportive of investing public funds for mosquito surveillance. However, participants across all focus groups expressed concerns over ecosystem health and long-term consequences of pesticide use for mosquito control. Participants in every focus group referenced a risk assessment that weighed the risk of MBD exposure against the use of chemical control: once participants perceived MBDs as negatively impacting human and/or animal health in their area, sentiment swung largely to supporting the use of pesticides. In the absence of an obvious MBD threat, participants preferred nonchemical control interventions. Participants felt communication from mosquito control agencies should be accessible, disseminated across multiple venues, and should include instructions for the public during spray events, resources for individual bite prevention, and information on control products used. Our research results can inform the development of improved, evidence-based MBD outreach and educational resources that are acceptable, actionable, and relevant to Northeast communities.

The mosquito species Aedes aegypti (Linneaus) is the vector of multiple arboviruses, including dengue, Chikungunya, Zika, and yellow fever. Risk of infections associated with these arboviruses continues to expand as the geographical range of Ae. aegypti extends into temperate regions. Although Ae. aegypti is abundant along the U.S.–Mexico border, the ecology of this mosquito species in this temperate/subtropical desert is not well understood. Our study objective was to estimate the seasonal population density in 2 urban communities: Sparks, El Paso, Texas and Anapra, Ciudad Juárez, Chihuahua, Mexico. Estimates of the population density of adult Ae. aegypti were obtained by month (June to December) and across years (2016 to 2018) using gravid traps. Mosquitoes were collected inside and outside a total of 108 and 101 participating homes in Sparks and Anapra, respectively. We determined multiple environmental and climatic factors influencing annual population trends. Generally, an increase in the abundance of Ae. aegypti was associated with an increase in precipitation, moderate temperatures, and high humidity, while months with temperatures below 4.4°C led to near absence of adults. Across months, we found low densities of Ae. aegypti during June and July, followed by near 100-fold increases in abundance from August to October before rapidly decreasing to near zero in subsequent cold season months. Our study sheds light on population dynamics and response variables at the leading edge of Ae. aegypti range, which require the development of targeted vector control measures for this mosquito species in this and other regions.

An aberrant bot fly specimen was removed from the scalp of a patient 3 wk after returning from Belize. The specimen showed little resemblance to the typical human bot fly larva, Dermatobia hominis, prompting a molecular identification using cytochrome oxidase I and II (COI and COII, respectively) mitochondrial DNA sequence regions. A BLAST search was subsequently performed, and both our COI and COII amplicon sequences showed 99–100% match with Dermatobia hominis, despite the specimen's clearly aberrant morphology.These findings suggest there is much wider variation in Dermatobia larval morphology than previously known or perhaps that there are new or cryptic species within this group.

Culex pipiens is an invasive mosquito found in temperate regions globally. It is considered among the most important disease vectors worldwide and is responsible for the transmission of a range of pathogens, including West Nile virus, avian malaria, Saint Louis encephalitis, and filarial worms. Throughout its northern temperate range, this mosquito is found in 2 ecotypes: form pipiens and form molestus. In Canada, this mosquito was previously thought restricted to the Pacific coast of British Columbia and the eastern provinces of Ontario, Quebec, and the Maritimes. Through routine mosquito surveillance and targeted trapping for Cx. pipiens, we detected this mosquito in 2 Albertan municipalities earlier than suggested by species distribution modeling based on climate change data. We confirmed the identity of putative Cx. pipiens specimens using DNA sequencing and found that alleles associated with form molestus were present, but at a low frequency compared to alleles associated with form pipiens. Furthermore, we compared the frequency of ecotype-related alleles in Alberta to elsewhere in North America and found a general trend of increased form pipiens in more northern latitudes, similar to previously reported results. We discuss our findings in the context of vector-borne disease activity in Canada, particularly West Nile virus.

The long-horned tick, Haemaphysalis longicornis Neumann (Ixodida: Ixodidae) was recently introduced to the United States from its native range in Asia. Although H. longicornis transmits numerous disease-causing pathogens in its native range, it is unclear to what extent H. longicornis will act as a disease vector in the United States. The ability of H. longicornis to acquire pathogens likely depends on overlap with resident tick species in both habitat and pathogens transmitted within its introduced range.To assess the potential overlap in habitat and pathogens between invasive H. longicornis and resident tick species, we field-collected ticks across southeastern Pennsylvania and tested them for pathogens. We then contextualized the risk of pathogen transmission to and by H. longicornis at sites where it overlaps with the current vector species using a network of vectored pathogens. None of the collected H. longicornis individuals tested positive for any pathogens. However, we found significant overlap in habitat use among H. longicornis and resident tick nymphs, as well as several overlaps in the pathogens vectored by resident ticks and those carried by H. longicornis in Asia. These findings indicate a high but yet-to-be-realized potential for H. longicornis to acquire North American tick-borne pathogens.

Myiasis is a parasitic infestation of soft vertebrate tissues by larval stages of Diptera. We briefly described the lesion-causing genus Cordylobia Grünberg (Diptera: Calliphoridae).Three Polish travelers to Uganda, Gambia, and Senegal returned with furuncular myiasis. To identify the third-instar larvae removed from their skin, we examined the morphological features of the 3 specimens and sequenced a 5' barcoding fragment of the cytochrome c oxidase subunit I gene (COI-5P). One larva was identified as C. rodhaini Gedoelst, and 2 larvae were identified as C. anthropophaga (Blanchard). We were the first to submit the COI-5P of C. rodhaini to GenBank and the Barcode of Life Database.This is the first record of the importation of C. anthropophaga and the second record of the importation of C. rodhaini to Poland.

A previous laboratory study using Haemaphysalis longicornis Neumann (Acari: Ixodidae) ticks of North American origin showed that larvae could acquire the Lyme disease spirochete, Borrelia burgdorferi sensu stricto (s.s.) (Spirochaetales: Spirochaetaceae) while feeding to completion on infected mice. However, the infection was lost during the molt to the nymphal stage. Nonetheless, questing H. longicornis nymphs and adults collected by drag sampling in the northeastern United States have been reported infected with B. burgdorferi s.s. DNA; occasionally these ticks appeared to be partially engorged. This raises the question of whether H. longicornis ticks can (i) acquire B. burgdorferi s.s. during an interrupted, partial blood meal on an infected host and (ii) transmit spirochetes while completing the blood meal on a second host. In this laboratory study, we demonstrated that H. longicornis nymphs could acquire B. burgdorferi s.s. from infected Mus musculus mice during a partial blood meal. Borrelia burgdorferi s.s. was detected by a multiplex polymerase chain reaction amplicon sequencing assay in 2 of 32 (6.3%) nymphs allowed to remain attached to infected mice for 48 h but, paradoxically, not in any of 25 nymphs that remained attached to infected mice for 72 h. Unfortunately, due to the low percentage of infected nymphs, we were not able to examine if such partially fed, infected nymphs were able to transmit B. burgdorferi s.s. while completing their blood meal on a second, naïve host.

Female ticks deposit large egg clusters that range in size from hundreds to thousands. These egg clusters are restricted to a deposition site as they are stationary, usually under leaf litter and other debris. In some habitats, these sites can be exposed to periodic flooding. When the clusters of tick eggs are disturbed, they may float to the surface or remain underneath organic debris entirely submerged underwater. Here, we examined the viability of egg clusters from winter ticks, Dermacentor albipictus, and lone star ticks, Amblyomma americanum, when partially or fully submerged in water and in relation to the developmental stages of the eggs under lab conditions. In general, egg clusters that were older and partially submerged had a higher viability than fully submerged, younger eggs. Of the two species, A. americanum was more resistant to water exposure. These studies highlight that egg clusters for certain tick species can remain viable when exposed to water for at least two weeks. These results also suggest that distribution by flooding of egg clusters could occur for some species and water submersion will differentially impact tick egg survival based on the specific developmental stage of exposure and species.

Dirofilariasis is a globally significant emerging-zoonotic-disease caused by nematode parasites belonging to the genus Dirofilaria (Rhabditida: Onchocercidae) and is transmitted by mosquitoes (Diptera: Culicidae) of the Culicidae family. A recent study on molecular prevalence of Dirofilaria sp. “hongkongensis” To, 2012 (nomen nudum) among the dog population in Kerala indicated a high infection rate. However, no data are currently available on the vectors involved in the transmission of this disease. In this study, an entomological survey was conducted to detect natural infection and to characterize the Dirofilaria parasite from Kani tribal settlements in Thiruvananthapuram, India. A total of 356 mosquitoes were collected, morphologically identified, and analyzed for natural infection of Dirofilaria from 4 different villages in the study area. The species composition of the collected mosquito specimens comprised 10 species belonging to 6 genera, namely Anopheles, Aedes, Armigeres, Culex, Uranotaenia, and Heizmannia. Aedes albopictus (Skuse, 1895) was found to be the predominant species, followed by Armigeres subalbatus Coquillett, 1898. Out of these, 200 female mosquitoes were grouped by species into 31 pools, for genomic DNA extraction. Detection of the nematode parasite was performed using nematode-specific primers via conventional PCR, and the species was subsequently confirmed by sanger sequencing. Natural-infection of Dirofilaria sp. “hongkongensis” was identified in Ae. albopictus and Ar. subalbatus, with a minimum infection rate of 17.6% and 13.3%, respectively. This study represents the first report of natural-infection of Dirofilaria sp. among field-collected mosquitoes in India. These findings underscore the need for robust entomological-surveillance system to prevent potential future outbreaks.

Graphical Abstract