Chagas disease is one of the most important vector-borne diseases in Latin America. Studying the biological parameters of each vector species or subspecies contributes to our understanding of their epidemiologic importan...Chagas disease is one of the most important vector-borne diseases in Latin America. Studying the biological parameters of each vector species or subspecies contributes to our understanding of their epidemiologic importance. The aim of our study was to compare the biological parameters and start to estimate the vectorial capacity of Ryckman, Ryckman, and their laboratory hybrids. Specifically, we estimated nine biological parameters to increase knowledge about the potential role of triatomine hybrids in the transmission of to reservoir hosts. Nine biological parameters related to the lifecycle, feeding and defecation patterns, number of females, fecundity, and egg eclosion rates in cohorts of , and their hybrids were evaluated and compared. Eight parameters (exception: number of laid eggs) indicated that was a potentially effective vector of Our results showed that the hybrid cohorts had better fitness and could potentially have higher vectorial capacity than the parental cohorts. The outstanding characteristics of the hybrids found in our study could lead to an increase in the epidemiologic risks caused by transmission of to humans.
Tick-borne diseases are an emerging public health threat in the United States, but surveillance is lacking in some regions. To advance current knowledge of the ecology of ticks and tick-borne diseases in South Dakota, we...Tick-borne diseases are an emerging public health threat in the United States, but surveillance is lacking in some regions. To advance current knowledge of the ecology of ticks and tick-borne diseases in South Dakota, we conducted a survey in the summer of 2019, focusing on the eastern counties of the state. We collected and identified 266 ticks and a subset were tested for the presence of by polymerase chain reaction (PCR). , a ubiquitous species in the state, was the most commonly identified tick, present in all counties surveyed. However, we also identified 15 from three different locations, providing the first evidence of established populations in the state and expanding the range of this species. In addition, we identified 22 from five different locations, confirming a previous report of an established population in the state. Two adult from two different sites were found to harbor including an individual from Lincoln County, suggesting the ongoing presence of the pathogen in tick populations in the state and representing its southwestern-most detection in the midwest United States. These findings provide important information for assessing and monitoring the public health risk from tick-borne diseases in an area where surveillance is lacking.
Blood sources used for insect colonies and their effects on fecundity and fertility have been studied in multiple mosquito species, but the effect of anticoagulants that prevent clotting of blood has received minimal att...Blood sources used for insect colonies and their effects on fecundity and fertility have been studied in multiple mosquito species, but the effect of anticoagulants that prevent clotting of blood has received minimal attention. Here, we identify the effect two anticoagulants have on the mortality, fecundity, and fertility of (Sebring and BCS strains) and Liverpool. Each mosquito species was provided with one of three treatments: direct feeding on live chicken (LC), blood from freshly exsanguinated chicken treated with heparin (EXS) or commercially purchased chicken blood treated with Alsever's solution (ART). No significant effect of treatment on mortality was observed. Both Sebring and BCS strains demonstrated a significant effect of treatment type on fecundity with the number of eggs laid for LC being 1.40-fold higher than EXS and 2.14-fold higher than ART for Sebring. For BCS strain mosquitoes, LC was 1.55-fold higher than ART, and EXS was 1.57-fold higher than ART, but there was no significant difference between LC and EXS. For mosquitoes, only a significant difference in mean egg counts was observed between LC and ART treatments, with LC laying 1.46-fold more eggs No significant effect on fertility was observed among any mosquitoes for any treatment. These results demonstrate the negative effect of anticoagulants on the fecundity for multiple mosquito taxa. This may affect the ability of labs to produce large numbers of mosquitoes or colonize wild mosquito populations and should be taken into account when considering colony maintenance or vector biology research.
We investigated the fauna in Turkey during the years 2016-2019 in the process of entomological surveillance for arboviral diseases. The entomological survey was conducted at 104 sampling stations in 51 provinces in Turk...We investigated the fauna in Turkey during the years 2016-2019 in the process of entomological surveillance for arboviral diseases. The entomological survey was conducted at 104 sampling stations in 51 provinces in Turkey during four consecutive years. There were approximately 450,000 specimens and 59 identified species collected during the surveillance. Ten species were newly recorded for Turkey: . , , , , , , , , , and . Identification of . and was confirmed using species-specific PCR and DNA sequencing. With our recent findings, previous data were critically reviewed and updated, and the number of species has been increased to 71 for Turkey. The presence of has particular importance due to its potential vector status for bluetongue virus (BTV) and Schmallenberg virus (SBV). This study presents result of the first large-scale integrated faunistic survey on species in Turkey.
(Skuse, 1894) has a widespread distribution that includes both temperate and tropical climates. It is a potential vector of several important worldwide arboviruses, including chikungunya, zika, and dengue, and its geogra...(Skuse, 1894) has a widespread distribution that includes both temperate and tropical climates. It is a potential vector of several important worldwide arboviruses, including chikungunya, zika, and dengue, and its geographical distribution expands rapidly. Despite its vectorial importance, the bioecological features of this species in newly established environments are still not very well known. Thus, this study investigated phenotypic variations among . populations from different regions in Turkey. This is the first comparative morphological study of . populations in Turkey. The procrustes distances phenogram derived from wing data indicates that the shape differences among some populations and the population from the Aegean coast differ from the Black Sea populations. Size differences were also detected between some populations.
We present the first records of () (Edwards, 1923) (n=15), () Ficalbi, 1890 (n=12), () Walker, 1856 (n=52), () (Stephens, 1825) (n=535), and () (Theobald, 1901) (n=54) in the Autonomous Community of Galicia (NW...We present the first records of () (Edwards, 1923) (n=15), () Ficalbi, 1890 (n=12), () Walker, 1856 (n=52), () (Stephens, 1825) (n=535), and () (Theobald, 1901) (n=54) in the Autonomous Community of Galicia (NW Spain), including the first evidence of the genus Dyar, 1904 in the northwest of Spain. The field research was carried out in different water ecosystems (ponds, streams, rivers, lakes, and lagoons) belonging to 39 zones throughout the entire Galician territory. The samples were collected intermittently and seasonally through different projects of water quality monitoring between 1998 and 2018. A total of 1,614 mosquito larvae have been analyzed, and 668 of them were identified as species not previously recorded in Galicia. Between 1999 and 2003, the first catches of these species were obtained and since then, more specimens have been detected in different wetlands of Galicia, mainly in spring and summer.
American trypanosomiasis is a zoonosis caused by the parasite and is transmitted mainly by blood-sucking insects belonging to the subfamily Triatominae. The importance of this parasite lies in its wide geographical dist...American trypanosomiasis is a zoonosis caused by the parasite and is transmitted mainly by blood-sucking insects belonging to the subfamily Triatominae. The importance of this parasite lies in its wide geographical distribution, high morbidity, and the fact that there has not yet been an effective treatment or vaccine. Previous studies have detailed the interactions between different triatomine species and strains. However, the factors necessary to establish infection in triatomines have not yet been fully elucidated. Furthermore, it is postulated that the coexistence between the parasite and triatomines could modulate the susceptibility to infection in these insects. Accordingly, in this study, we evaluated the susceptibility to infection in the species () , , and , which were infected with Ninoa, H8, INC-5, Sontecomapan, and Hueypoxtla strains. The criteria used to establish susceptibility were the amount of blood ingested by the insects, percentage of infected triatomines, concentration of parasites in feces, and percentage of metacyclic trypomastigotes in feces. These parameters were analyzed by fresh examination and differential count with Giemsa-stained smears. Our main findings suggest the following order of susceptibility concerning infection with : > > . () . Furthermore, the study concludes that an increased susceptibility to infection of triatomines that share the same geographic region with different strains of is not always a fact.
An important element of vector control and surveillance of mosquito-borne diseases is updated information on vector species distribution. The aim of this study was to collect available information about mosquito species...An important element of vector control and surveillance of mosquito-borne diseases is updated information on vector species distribution. The aim of this study was to collect available information about mosquito species reported in Extremadura between 1920 and 2020 and create a catalog that would combine both published data and our recent field identifications. An exhaustive list is hereby presented, including species status and detailed distribution maps at a municipal level as well as their importance for public health. A total of 33 species, classified into five genera: (five species), (14), (nine), (four), and (one) has been recorded, including 31 autochthonous, one invasive, () , and one disappeared since 1953, () . For the first time in Extremadura, we report the presence of important vectors such as () and () , and the new record of six species in the province of Badajoz, namely: () () () , () , () , and (. Nineteen of these species are potential vectors of medical and veterinary relevance.
Global climate change and the accompanying rise in temperature could affect the biology and ecology of a number of vectors, including mosquitoes. High altitude areas that were previously unsuitable for the spread of mosq...Global climate change and the accompanying rise in temperature could affect the biology and ecology of a number of vectors, including mosquitoes. High altitude areas that were previously unsuitable for the spread of mosquito vector populations could become suitable. The aim of this research was to study the distribution of mosquito species in higher altitude regions of Croatia. Samples were collected in three areas: Slavonian Mountains, Gorski Kotar, and Middle Velebit. Specimens were morphologically determined and confirmed by DNA barcoding and other genetic markers and showed the presence of 16 species belonging to six genera. The most abundant species were the complex with 50% of the collected specimens. Both (Linnaeus, 1758) and (Forskal, 1775) biotypes and their hybrids were identified within the complex, followed by (Martini, 1925) (20.2%), (Macquart, 1838) (8.5%), and the invasive species (Theobald, 1901) (7.8% of the total number of collected specimens). The remaining 12 species made up 14.7% of the collected specimens. Intraspecific COI p-distances were within the standard barcoding threshold for OTUs, while interspecific genetic distances were much higher, confirming the existence of barcoding gaps. Mosquito fauna of Croatian mountains showed a moderate variety and made 30.8% of the total number of recorded mosquito species in Croatia thus far.
Several important biological parameters for estimating the vectorial capacity of a triatomine species were determined on a Mexican population of the recently described Lima-Cordón, Monroy, Stevens, Rodas, Rodas, Dorn, J...Several important biological parameters for estimating the vectorial capacity of a triatomine species were determined on a Mexican population of the recently described Lima-Cordón, Monroy, Stevens, Rodas, Rodas, Dorn, Justi (Hemiptera: Reduviidae: Triatominae). The biological parameters were the egg-to-adult development time, number of blood meals required for molting, cumulative mortality, onset time for feeding, feeding and defecation behaviors, and fertility and fecundity of The median egg-to-adult development time was 253 days, with 11 blood meals required for molting. A cumulative mortality rate of 47.41% was observed. The time to begin feeding was between 2.5 and 3.5 min. Feeding times were longer than 15 min. The highest percentages of defecation delays were 1 to 10 min in all nymphal instars and also in males. In contrast, significantly ( < 0.01) more females defecated while eating. At the end of the cycle, the percentage of the obtained females was 54.9%. The mean number of eggs laid per day per female for a month was 2.08. These eggs had an eclosion rate of 98.08%, with an incubation period of 19 days. Our results contribute to estimations of the potential role of in the transmission of in its distribution area.
During the course of a plague epizootic, decimation of rodent host populations may result in the transfer of fleas to alternate or phoretic hosts, including to sympatric raptors that prey on rodents. We studied flea abun...During the course of a plague epizootic, decimation of rodent host populations may result in the transfer of fleas to alternate or phoretic hosts, including to sympatric raptors that prey on rodents. We studied flea abundance and flea species assemblages on burrowing owls () in southwestern Idaho before (2012 - 2014), during (2015 - 2016), and after (2017) an epizootic of plague in Piute ground squirrels (). We examined (1) if a larger proportion of burrowing owl nests contained fleas, (2) the likelihood that owls within a high flea abundance class increased, and (3) if owls harbored ground squirrel fleas during the epizootic. Using a flea abundance index assigned to 1,184 owls from 236 nests, the proportion of nests and the likelihood that owls had high flea abundance decreased rather than increased during epizootic years. Moreover, of 3,538 collected fleas from owls at 143 nests, no fleas were species that Piute ground squirrels typically harbor. Instead, was the predominant flea collected in all study years (> 99%). Thus, although raptors may play a role in plague, there was no evidence that the die-off of ground squirrels resulted in higher flea intensity in burrowing owls or that they served as frequent accidental or phoretic hosts for ground squirrel fleas that could potentially be infectious with .
Anthropogenic land-use change may affect the transmission risk for endemic vector-borne diseases such as La Crosse encephalitis. In this study, we applied a comparative ecological approach to evaluate differences in vect...Anthropogenic land-use change may affect the transmission risk for endemic vector-borne diseases such as La Crosse encephalitis. In this study, we applied a comparative ecological approach to evaluate differences in vector species abundance, gonotrophic status, and environmental variables among six residential habitats (historical case houses) and six paired adjacent forest patches in a La Crosse virus endemic area of North Carolina. A total of 93,158 container spp. eggs were obtained by ovistrips and 1,040 resting mosquito adults were collected by large-bore aspiration from 10 June through 8 October, 2010. At sites characterized by high densities of artificial containers, the totals of eggs and adult mosquitoes were higher in the peridomestic plots. At sites characterized by lower densities of artificial containers, the totals of eggs and adult mosquitoes were higher in the forested plots. Although , the primary La Crosse virus vector, was more commonly found in forested habitat overall, in sites characterized by high density of artificial containers, it was found in higher abundance in the peridomestic habitat. Similarly, the proportion of gonotrophically active (parous and gravid) mosquitoes was higher in the peridomestic habitat for sites with highartificial container density. Our study suggests that La Crosse virus transmission risk may be higher at peridomestic habitats with higher densities of artificial containers and thus reinforces the importance of public health measures to improve source reduction efforts
Attractive toxic sugar baits (ATSB) are a novel and effective mosquito control tool based on sugar-feeding behaviors and oral ingestion. In general, there is a demand from consumers for more novel control products with m...Attractive toxic sugar baits (ATSB) are a novel and effective mosquito control tool based on sugar-feeding behaviors and oral ingestion. In general, there is a demand from consumers for more novel control products with more effective active ingredients. (BTi) is a major larvicide for control of mosquito larvae. This study evaluated BTi as an active ingredient of toxic sugar baits (TSB) against adult , , and compared with a positive control of 1% boric acid toxic sugar bait. Ingestion of BTi TSB by female mosquitoes resulted in an average mortality at 48 h of 97% for , 98% for , and 100% for . The study findings suggest ingestible BTi TSBs could be a viable alternative to current mosquito control strategies and programs against adults of these three species of mosquitoes.
The colonization of the African malaria vector has been hampered by inadequate knowledge of its mating and development under laboratory conditions. Life-tables are routinely used to provide baseline biological character...The colonization of the African malaria vector has been hampered by inadequate knowledge of its mating and development under laboratory conditions. Life-tables are routinely used to provide baseline biological characteristics needed for colonization. This study characterized age-specific life-table attributes of an existing laboratory strain to gain insight into factors that are critical for its colonization. To achieve this, the laboratory strain was reared from eggs to adulthood under standard insectary conditions, monitoring and characterizing each developmental stage. The mean insemination rate of females was 74.8% with an average egg load of 67.1 eggs/female and a mean fertility of 86.7%. The mean developmental time from 1 instar larvae (L1) to pupation was 16.4 days. The mean proportion of L1 that survived to pupation was 72.9%. On average, 78.8% of the pupae successfully eclosed as adults. The median longevity for adult males and females was 44 and 28 days, respectively. This work constitutes the first report on life-table characterization of an strain. The larval developmental time was within the range reported for wild while adult longevity was higher compared to survivorship observed in wild populations. These data demonstrate that the colonized strain has potential to be re-colonized under standard insectary conditions. The study provides base-line information for further studies on identifying critical parameters for the maintenance of under artificial conditions.
Variation in vector traits can modulate local scale differences in pathogen transmission. Here, we compared seasonal variation in the wing length (proxy for body size) and energy reserves of adult wild-caught population...Variation in vector traits can modulate local scale differences in pathogen transmission. Here, we compared seasonal variation in the wing length (proxy for body size) and energy reserves of adult wild-caught populations from a dengue endemic (Kilifi) and non-endemic (Isiolo) area of Kenya. Vector sampling in the dengue endemic site was conducted during the dry and wet seasons. In the non-endemic area, it was limited to the dry season which characterizes this ecology where sporadic or no rainfall is commonplace during the year. We found variation by site in the body size of both sexes, with an overall smaller size of populations collected from Isiolo than those from Kilifi. Our results show that although total carbohydrates and lipids levels were highest in both sexes during the dry season, they were two-fold higher in males than females. However, we found weak correlations between body size and energy reserves for both sexes, with body size being more sensitive in identifying differences at a population level. These results provide insights into the determinants of the vectoring potential of populations in dengue endemic and non-endemic ecologies in Kenya.
Habitat preference and usage by disease vectors are directly correlated with landscapes often undergoing anthropogenic environmental change. A predominant type of land use change occurring in the United States is the exp...Habitat preference and usage by disease vectors are directly correlated with landscapes often undergoing anthropogenic environmental change. A predominant type of land use change occurring in the United States is the expansion of native and non-native woody plant species in grasslands, but little is known regarding the impact of this expansion on regional vector-borne disease transmission. In this study, we focused on the impact of expanding eastern redcedar (; ERC) and tested two hypotheses involving relationships between habitat preferences of adult tick species in rural habitats in central Oklahoma. Using CO traps, we collected ticks from two densities of ERC and grassland and screened adult ticks for the presence of pathogen DNA. We found support for our first hypothesis with significantly more (Linnaeus) and (Say) collected in ERC habitats than in grassland. Our second hypothesis was also supported, as - and -infected were significantly more likely to be collected from ERC habitats than grassland. As the first evidence that links woody plant encroachment with important tick-borne pathogens in the continental United States, these results have important ramifications involving human and companion animal risk for encountering pathogen-infected ticks in the southern Great Plains.
We present the first records of Anopheles (Anopheles) plumbeus Stephens, 1828 and Culex (Culex) torrentium Martini, 1925 in the autonomous region of Galicia (NW Spain), obtained through the Rede Galega de Vixilancia de V...We present the first records of Anopheles (Anopheles) plumbeus Stephens, 1828 and Culex (Culex) torrentium Martini, 1925 in the autonomous region of Galicia (NW Spain), obtained through the Rede Galega de Vixilancia de Vectores (ReGaViVec). This entomological surveillance network, which was initiated in 2017 by the Xunta de Galicia in collaboration with the University of Vigo and the University of Santiago de Compostela, aims to detect the arrival of invasive vectors as well as to improve the knowledge about mosquito populations (Diptera: Culicidae) in the Galician territory. This study shows the first findings of these species in Galicia, which have been reported in six different locations throughout the region: five in the province of Pontevedra and one in the province of Lugo. The 51 captured specimens were collected at different stages of development between July and September, 2018 and 2019 by using specialized traps arranged in favorable regions for the settlement and development of culicids.