Eradicating screwworm, Cochliomyia hominivorax (Coquerel), from continental North American via the sterile insect technique has provided huge economic benefit to livestock producers by eliminating screwworm myiasis. After confirmatory identification of fly samples from infested deer by the USDA National Veterinary Services Laboratory on September 30, 2016, an alert was issued that screwworm myiasis was discovered in the Florida Keys. Personnel from USDA Animal and Plant Health Inspection Service, Agricultural Research Service, the State of Florida, U.S. Fish and Wildlife Service and local officials responded to the outbreak focus on Big Pine Key. After witnessing infested Key deer (Odocoileus virginianus clavium Barboyr & Allen), screwworm adult sampling was initiated at 0930 h on October 5, 2016 using nets to collect flies arriving at putrid liver, with the first female collected within 1 h. Larval samples were collected from infested animals for DNA analyses and to develop a “Florida outbreak” colony to test mating compatibility with the mass-produced strain used for sterile fly releases. Ground release chambers for sterile screwworm releases were placed in favorable habitats based on satellite image analyses. Sterile pupae were first placed in the chambers on October 11, 2016. Further liver trapping showed that 13 Keys were infested. One case, presumably through animal movement, occurred near Homestead on the Florida mainland. Ultimately there were 35 sterile fly release stations, including 4 located around Homestead, but no further cases were identified. About 188 million sterile flies were released until successful eradication was declared on March 23, 2017. Containing the outbreak prevented economic losses to livestock producers and other wildlife on the mainland and kept eradication costs to a minimum.

Efforts to develop mosquito attractants using vertebrate host volatiles have been well made under laboratory conditions but their attractiveness to mosquitoes in the wild still needs to be evaluated. In the present study, we evaluated the attraction of female Culex pipiens pallens Coquillett (Diptera: Culicidae) to 11 individual chemical compounds found in vertebrate host odors, and to synthetic blends, consisting of different combinations of the compounds. These tests were conducted under laboratory and field conditions using a Y-tube olfactometer and odorbaited traps, respectively. When delivered at concentrations ranging from 0.1 to 10.0 μg/kg, 9 of the 11 compounds were attractive to female mosquitoes under laboratory conditions. We developed 47 synthetic blends composed of the 6 most attractive compounds (propionic acid, hexanal, myristic acid, benzaldehyde, 1-octen-3-ol, and geranyl acetone) and 18 of them were significantly attractive to mosquitoes in the olfactometer. Most of the attractive blends contained two to four attractive compounds. In the field, 5 of the 18 blends captured significantly more mosquitoes than did control traps. The findings demonstrate that female mosquitoes can be attracted by single chemical compounds as well as some of their synthetic blends. The effectiveness of synthetic blends depended on specific combinations of several compounds, rather than simply increasing the number of attractive compounds in the blends. Synthetic blends may have potential for use in odor-baited traps for mosquito surveillance.

Invasive container mosquito species Aedes aegypti (L.) and Ae. albopictus (Skuse) frequently co-occur in nature where they are typically segregated spatially by distinctive macrohabitat preferences that may select for different oviposition strategies. In a standard cage environment, we compared oviposition site selection by individual gravid females of these species exposed to variable numbers of water-holding cups and the presence or absence of a rugose wettable container lining. Offered plastic cups with and without lining, both species laid a significantly higher percentage of eggs in cups with lining (95.3% for Ae. aegypti, 88.4% for Ae. albopictus), than in cups without (4.7% for Ae. aegypti, 11.6% for Ae. albopictus). Linear regressions of container availability versus the number of lined cups colonized were similar for Ae. aegypti and Ae. albopictus. Rates of oviposition on the water surface differed by species for both cup types, with Ae. albopictus laying a higher percentage of eggs on the water surface in cups without lining (28.1% for Ae. aegypti, 51.3% for Ae. albopictus), than in cups with (5.3% for Ae. aegypti, 2.5% for Ae. albopictus).The more varied oviposition strategies of Ae. albopictus are interpreted in the context of its broader macrohabitat use and inferior egg desiccation resistance.

Laboratory experiments intended to test the effects of a purported ovipositional deterrent pheromone of Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) led instead to the finding that egg cannibalism by fourth-instar larvae explained the ‘deterrent effect’ rather than chemical signals from larvae. Virtually no eggs were counted from cups containing fourth-instar larvae, after oviposition. Numbers of eggs from cups containing younger, conspecific larvae, or pupae did not differ significantly from water only control. Video recording of larval behavior revealed that fourth-instar larvae consumed entire eggs in one continuous ingestive bout. Egg output in the presence of fourth-instar larvae with their mouthparts sealed was similar to the larvae-absent treatment, but nearly 100-fold greater than that counted in the presence of fourth-instar larvae that could eat freely. Thus, the huge egg reduction in eggs counted in the presence of fourth-instar larvae was due to egg cannibalism, not because presence of these larvae deterred oviposition as has been reported in previous studies.Third and especially fourth-instar larvae also cannibalized newly hatched first-instar larvae. Artificial food availability did not eliminate but did reduce cannibalism during first several hours of exposure. The rate at which fourth-instar larvae consumed conspecifics rose significantly and linearly with prey density, generating a non-plateauing, type I functional response curve.These results clearly show that care must be taken such that mosquito ovipositional experiments are not confounded by presence of cannibalizing larvae.

Simulium quinquestriatum Shiraki (Diptera: Simuliidae), a human-biting fly that is distributed widely across Asia, is a vector for multiple pathogens. However, the larval development of this species is poorly understood. In this study, we determined the number of instars in this pest using three batches of field-collected larvae from Guiyang, Guizhou, China. The postgenal length, head capsule width, mandibular phragma length, and body length of 773 individuals were measured, and k-means clustering was used for instar grouping. Four distance measures—Manhattan, Euclidean, Chebyshev, and Canberra—were determined. The reported instar numbers, ranging from 4 to 11, were set as initial cluster centers for k-means clustering. The Canberra distance yielded reliable instar grouping, which was consistent with the first instar, as characterized by egg bursters and prepupae with dark histoblasts. Females and males of the last cluster of larvae were identified using Feulgen-stained gonads. Morphometric differences between the two sexes were not significant. Validation was performed using the Brooks–Dyar and Crosby rules, revealing that the larval stage of S. quinquestriatum is composed of eight instars.

The goal of this study was to evaluate the use of stable isotope labeled compounds to better understand factors influencing energy turnover in larval Culex quinquefasciatus (Say; Diptera: Culicidae). Three isotope labeled compounds were evaluated in this study, including ¹⁵N-labeled potassium nitrate, ¹³C-labeled glucose, and ¹³C-labeled leucine. Conditions were first optimized in the laboratory to determine the most appropriate concentration of isotope, as well as the half-life of enrichment. Once optimum conditions were established we used standard equations to predict and determine temperature and density-dependent energy turnover rates. Our results showed that higher concentrations of isotope had an impact on mosquito survivability, overall enrichment, and adult wing length. We predicted the half-life of to be around 0.614 to 0.971 d, and our observed half-lives were determined to be 0.72 to 1.44 d depending on temperature, larval density, and isotope compound. Both density and temperature had a strong influence on isotopic turnover rates in all isotopes evaluated. Our results suggest that stable isotopes can provide a useful tool in understanding how different stress factors influence energy turnover in larval Cx. quinquefasciatus. These data can also help lay a foundation on ways to improve larvicide efficacy under different biotic and abiotic conditions.

Insects display different patterns of development, and blow flies have one of the most specialized patterns of intrapuparial development of all. In forensic entomology, pupae can be used as a tool to estimate the minimum postmortem time interval (_minPMI). We analyzed the intrapuparial development of Chrysomya albiceps (Diptera: Caloricidade) whose larvae had been fed pig lungs and reared in a climate-controlled room at 28°C day/26°C , night, 70 ± 10% RH, and 12 h of photophase and monitored daily. After the third-instar larvae abandoned their diet, the process of pupariation and pupation was monitored. At pre-established times, five pupae were collected, euthanized, and fixed in 5% formaldehyde, inside polypropylene test tubes with caps. Since they were the first, they were classified as 0 h pupae.Twelve collections occurred until the emergence of the adults, at 0, 2, 4, 6, 8, 10, 24, 30, 48, 54, 72, 78, 96, and 99 h (n = 84).The fixed pupae were dissected under the microscope, with the aid of anatomical tweezers and hypodermic needles, and photographed. The stages of metamorphosis and the morphological alterations occurring during the process were identified, described, and recorded before and after pupation. These phases were: pupation, larval pupal apolysis, cryptocephalic, phanerocephalic, pharate adult, emergence, and adult.The cryptophalic phase occurred between 4 and 6 h after pupation; the phanerocephalic phase between 6 and 10 h after; the pharate adult phase between 24 and 96 h after; and the imago/emergence phase 99 h after pupation.

Insecticidal indoor residual wall treatment is a major tool for the control of malaria, with the goals of reducing indoor vector density and vector life span, in addition to reducing transmission rates of disease. Dynamics of the malaria vector, Anopheles gambiae, in the Emutete region in the Western Kenya highlands are based on an already existing model in the literature. In this paper, the framework is used to predict vector reduction due to four types of indoor wall treatments: two cases of indoor residual spraying of DDT and two types of pyrethrin-based INESFLY insecticidal paint. These treatments differ primarily in the duration of their persistence on walls. The model shows the extent of suppression of vector abundance over time due to each of the four treatments. It predicts that indoor residual spraying may have no noticeable effect at all if the percent coverage is not high enough or the persistence of the mortality effect is low, but will have a substantial effect at higher coverage rates and/or higher persistence. For treatments with longer persistence of mortality, the model predicts a coverage threshold above which extra treatment has little to no effect. For treatments of short persistence of mortality, the seasonal timing of treatment has a noticeable effect on the duration of vector suppression. Overall, the model supports claims in the literature that wall treatments have the capacity to reduce the vector burden.

Sand fly fever is caused by Naples (SFNV) and Sicilian viruses (SFSV) and the closely related Toscana virus of the Phlebovirus genus in the family Bunyaviridae, and transmitted by Phlebotomine sand flies. Phlebotomus papatasi Scopoli, 1786 is known as the main vector of the disease. This study aimed to investigate the distribution of Phlebotomine sand flies as vector of sand fly fever viruses, and the effects of some environmental variables on their potential dispersion to new areas in some provinces of Iran. Sand flies were collected during their active season in the region using CDC light traps. Ecological parameters were recorded for each collection site. Arc GIS 10.3 software was used for data analysis and mapping the distribution of sand flies. Sampling in the study areas was carried out in six different climatic zones. Seventeen sand fly species were collected including eight species of genus Phlebotomus and nine species of genus Sergentomyia.The Medium Semi-Arid climatic zone had the highest species diversity. Fourteen species of sand flies were collected at altitude between 2 and 325 m, and seven species were collected between 326 and 1380 m above sea level.There was significant correlation between sand fly density and all tested environmental variables. Phlebotominae sand flies have wide distribution in Iran and have a major public health concern in the country. P. papatasi and Sergentomyia sintoni Pringle, 1933 prefers hot summers and rainfall.This poses a threat of transmission of sand fly fever caused by SFSV and SFNV across the country.

Tsetse flies (Glossina) are vectors of African trypanosomiasis. Olfaction plays a critical role in Glossina behavior, including larviposition, feeding, and reproduction. Odorant receptors (ORs) are important in insect chemoreception as they bind volatile odorants and transport them to olfactory receptor neurons to elicit behavioral response.To better understand Glossina chemoreception, we used quantitative polymerase chain reaction to examine the expression levels of ORs in female and male Glossina morsitans morsitans Wiedemann, 1850 (Diptera: Glossinidae) antennae and legs. Results showed that G. m. morsitans ORs code for a transmembrane domain and are involved in odorant binding. The ORs had homologs in Drosophila, mosquitoes, other Glossina species, and the reduced number of tsetse ORs could be linked to its restricted blood-feeding diet. The OR genes were more highly expressed in antennae than the legs with GmmOR33 and GmmOR45 transcript levels being high in the female and male antennae, respectively, whereas GmmOR26 and GmmOR34 levels were high in female and male G. m. morsitans legs, respectively. These findings identified sex- and tissue-specific G. m. morsitans ORs. The expression levels of OR genes in female and male G. m. morsitans could be conserved in function with the antenna being the main olfactory organ.Thus, this study provides a blueprint to explore the functional roles of tsetse ORs with the potential to identify molecular targets that can be used to control the vector based on disruption of its chemosensory system.

G-protein-coupled receptors (GPCRs) are a large family of seven-transmembrane domain proteins that exist in plants and animals, playing critical physiological functions through intracellular cascades. Previous studies revealed an important regulation pathway of GPCR/Guanine nucleotide-binding protein (G-protein)/Adenylyl Cyclase (AC)/ cAMP-dependent protein kinase A (PKA) in the insecticide resistance and regulation of resistance-related P450 gene expression in highly resistant southern house mosquitoes, Culex quinquefasciatus Say (Diptera: Culicidae). However, the function of this regulation pathway in field-collected and laboratory-susceptible mosquitoes is still unknown. In the current study, we characterized the function of each effector (GPCR, G-protein, AC, and PKA) in this GPCR intracellular pathway in both field-collected and laboratory Cx. quinquefasciatus strains, showing that knockdown of the expression of each effector gene can cause 1) decreased expression of their downstream respective genes and 2) increased sensitivity of the mosquitoes to permethrin insecticide. These results, together with our previous findings, strongly suggest the universal function of the GPCR-regulation cascade in the mosquito's sensitivity to insecticides and its regulation of resistance development through P450-mediated detoxification.

Dermacentor parumapertus Neumann (Acari: Ixodidae), a tick primarily associated with rabbits which occurs over much of the western United States, has a fairly large north-to-south distribution, being found from central Idaho southward into northern Mexico. This mostly obscure tick species has recently been the focus of attention due to the discovery of a unique strain of Rickettsia parkeri associated with it which appears closely related to a Rickettsia sp. found in the Atlantic rainforest of Brazil. Historically, a morphological variety of this species was reported in the literature based on significant variation in ornamentation of the tick throughout its range. This study examines several key morphological characters to determine if there are indeed more than one distinct population of this species throughout its range.

The fourth instar larva and pupa of Culicoides trilineatus Fox (Diptera, Ceratopogonidae), a species considered as potential vector of the bluetongue virus in Central and South America, are described, illustrated, and photomicrographed for the first time by using binocular, phase-contrast, and scanning electron microscopy. The immatures were collected by using a siphon bottle in tree holes in Salta Province, Argentina, transported to the laboratory, and there reared to the adult's emergence. They are compared with the immatures of Culicoides debilipalpis Lutz (Diptera, Ceratopogonidae), another Neotropical species that develops in tree holes. Details on larval biology and habitat are given.

A new black fly species, Simulium haiduanenseTakaoka, Low & Huang (Diptera: Simuliidae), is described on the basis of females, males, pupae, and mature larvae from Taiwan. This new species is placed in the Simulium argentipes species-group of the subgenus Simulium (Diptera: Simuliidae) and is characterized by the yellowish female legs, ovipositor valves rounded apically and with its inner margin concave, claw with a small subbasal tooth, male style without a basal protuberance, pupal gill with eight filaments, corbicular cocoon, and larval abdomen lacking paired protuberances. It represents the first record of the S. argentipes species-group from Taiwan. Taxonomic notes are given to separate this new species from all eight species in the same species-group.The phylogenetic relationships of this new species with four related species are presented.

Sand fly (Diptera: Psychodidae) taxonomy is complex and time-consuming, which hampers epidemiological efforts directed toward controlling leishmaniasis in endemic regions such as northeastern Brazil. Here, we used a fragment of the mitochondrial cytochrome c oxidase I (COI) gene to identify sand fly species in Maranhão State (northeastern Brazil) and to assess cryptic diversity occurring at different spatial scales. For this, we obtained 148 COI sequences of 15 sand fly species (10 genera) from Maranhão (fine spatial scale), and joined them to COI sequences from other Brazilian localities (distant about 2,000 km from Maranhão, broad spatial scale) available in GenBank.We revealed cases of cryptic diversity in sand flies both at fine (Lutzomyia longipalpis (Lutz and Neiva) and Evandromyia termitophila (Martins, Falcão and Silva)) and broad spatial scales (Migonemyia migonei (França), Pressatia choti (Floch and Abonnenc), Psychodopygus davisi (Root), Sciopemyia sordellii (Shannon and Del Ponte), and Bichromomyia flaviscutellata (Mangabeira)). We argue that in the case of Bi. flaviscutellata, the cryptic diversity is associated with a putative new species. Cases in which DNA taxonomy was not as effective as morphological identification possibly involved recent speciation and/or introgressive hybridization, highlighting the need for integrative approaches to identify some sand fly species. Finally, we provide the first barcode sequences for four species (Brumptomyia avellari (Costa Lima), Evandromyia infraspinosa (Mangabeira), Evandromyia evandroi (Costa Lima and Antunes), and Psychodopygus complexus (Mangabeira)), which will be useful for further molecular identification of neotropical species.

A new species of phlebotomine sand fly is described and illustrated based on male and female specimens collected in rural and semi-urban areas of the Chaco Province, Argentina. A separation of the Cortelezzii series in two species complexes is proposed, as is a species key for its identification. The morphological characters of the new species permit its inclusion in the Cortelezzii series of genus Evandromyia, subgenus Barrettomyia (Diptera: Psychodidae). The species is named Evandromyia chacuensis sp. nov. Szelag, Rosa, Galati, Andrade Fhilo & Salomón (Diptera: Psychodidae).

Lemurpediculus madagascariensis sp. nov. (Phthiraptera: Anoplura: Polyplacidae) is described from the Gray Mouse lemur, Microcebus murinus (J. F. Miller) (Primates: Cheirogaleidae), from Ankarafantsika National Park, Madagascar. Lemurs were trapped using Sherman Live Traps and visually inspected for lice, which were preserved in 90% ethanol. Adults of both sexes and the third-instar nymph of the new species are illustrated and distinguished from the four previously known species of Lemurpediculus: L. verruculosus (Ward); L. petterorum Paulian; L. claytoni Durden, Blanco, and Seabolt; and L. robbinsi Durden, Blanco, and Seabolt. It is not known if the new species of louse is a vector of any pathogens or parasites.

Forensic entomology is a complementary tool for penal procedures, mainly on estimating postmortem interval. Study of cadaveric fauna in various environments is primary as source of information to support this science. This study collected information about the fauna of Calliphoridae associated to carcasses of Rattus rattus in the Tijuca National Park, RJ. Four collections were conducted, one for each season of 2015, exposing six carcasses at georeferenced points in each collection. The carcasses were placed 550 m from the boarder and equidistant by 100 m. Five decomposition stages were identified, and 10,559 individuals of Calliphoridae belonging to 10 species were collected. The most abundant species were Hemilucilia semidiaphana (Rondani) (Diptera: Calliphoridae) and Lucilia eximia (Wiedemann) (Diptera: Calliphoridae). L. eximia was the most abundant species during the Swelling and Black Putrefaction stages, succeeded in the next stages by two species of the genera Hemilucilia. H. semidiaphana was the dominant species in the last two stages, followed by Hemilucilia segmentaria (Fabricius) (Diptera: Calliphoridae). The genus Mesembrinella (Diptera: Calliphoridae) occurred mainly during the Black putrefaction stage. Mesembrinella bellardiana (Aldrich) was more abundant, with higher occurrence during the Black putrefaction and Dry decay stages. Mesembrinella peregrina (Aldrich) occurred in the two last stages with low abundance. Huascaromusca aeneiventris (Wiedemann) (Diptera: Calliphoridae) occurred during all the observed stages, mainly during the Butyric fermentation stage. Huascaromusca purpurata (Aldrich) (Diptera: Calliphoridae) occurred only during the Dry decay stage and in low abundance. A succession pattern in the carcasses colonization was observed, providing relevant information for the resolution of criminal investigations in this environment.

For over two decades, the bed bug, Cimex lectularius L. (Hemiptera: Cimicidae) has been undergoing a dramatic global resurgence, likely in part to the evolution of mechanisms conferring resistance to insecticides. One such mechanism is knock-down resistance (kdr), resulting from nonsynonymous mutations within the voltage-gated sodium channel (VGSC) gene. To date, three mutations have been identified in C. lectularius, V419L, L925I, and I936F. Using Sanger sequencing, the frequency and distribution of these VGSC mutations across 131 populations collected from the bat-associated and human-associated lineages of C. lectularius found in Europe are documented. All populations from the bat-associated lineage lacked mutations at the three sites. In contrast, the majority of populations associated with humans (93.5%) possessed the mutation at the L925I site. The I936F mutation, previously only reported in Israel and Australia, was found in nine populations spread across several European countries, including the Czech Republic and Switzerland. The high frequency of kdr-associated resistance already reported in C. lectularius and the occurrence and broad geographic distribution of this additional VGSC mutation, questions the continued use of pyrethroids in the treatment of infestations.

Head lice infest millions of school-age children every year, both in developed and developing countries. However, little is known about the number of lice transferred among children during school activities, because direct methods to study this are almost impossible to implement. This issue has been addressed following an indirect method, which consist in collecting data of real infestation from several children groups and using a mathematical model of lice colonies to infer how the infestation observed might have evolved. By determining the events that would most likely lead to infestations as those observed, we find that severe infestations are most likely initiated by a relatively large number of lice transferred at the same moment or within relatively short time spans. In turn, analysis of the data obtained from screenings of the same groups of children a few days apart shows evidence of such transmission events. Interestingly, only children with severe infestations could harbor the lice necessary for this type of transmission.Thus, they play the same role as ‘superspreaders' in epidemiology. As part of our experimental study it is also shown that a simple procedure of combing can be very effective to remove all mobile lice, and thus could be used as an effective preventive measure against those severe infestations that are responsible for the spread of pediculosis.

New World screwworm (NWS), Cochliomyia hominivorax (Coquerel 1858) (Diptera: Calliphoridae), is a myiasis-causing fly that can be a serious threat to the health of livestock, wildlife, and humans. Its progressive eradication from the southern United States, Mexico, and Central America from the 1950s to 2000s is an excellent example of successful pest management using sterile insect technique (SIT). In late 2016, autochthonous NWS were detected in the Florida Keys, representing this lspecies' first invasion in the United States in >30 yr. Rapid use of quarantine and SIT was successful in eliminating the infestation by early 2017; however, the geographic source of this infestation remains unknown. Here, we use amplicon sequencing to generate mitochondrial and nuclear sequence data representing all confirmed cases of NWS from this infestation, and compare these sequences to preexisting data sets sampling the native distribution of NWS. We ask two questions regarding the FL Keys outbreak. First, is this infestation the result of a single invasion from one source, or multiple invasions from different sources? And second, what is the geographic origin of this invasion? We found virtually no sequence variation between specimens collected from the FL Keys outbreak, which is consistent with a single source of introduction. However, we also found very little geographic resolution in any of the data sets, which precludes identification of the source of this outbreak. Our lack of success in answering our second question speaks to the need for finer-scale genetic or genomic assessments of NWS population structure, which would facilitate source determination of potential future outbreaks.

Studies of the pre-colonization interval and mechanisms driving necrophilous insect ecological succession depend on effective sampling of adult insects and knowledge of their diel and successional activity patterns. The number of insects trapped, their diversity, and diel periodicity were compared with four sampling methods on neonate pigs. Sampling method, time of day and decomposition age of the pigs significantly affected the number of insects sampled from pigs. We also found significant interactions of sampling method and decomposition day, time of sampling and decomposition day. No single method was superior to the other methods during all three decomposition days. Sampling times after noon yielded the largest samples during the first 2 d of decomposition. On day 3 of decomposition however, all sampling times were equally effective. Therefore, to maximize insect collections from neonate pigs, the method used to sample must vary by decomposition day. The suction trap collected the most species-rich samples, but sticky trap samples were the most diverse, when both species richness and evenness were factored into a Shannon diversity index. Repeated sampling during the noon to 18:00 hours period was most effective to obtain the maximum diversity of trapped insects. The integration of multiple sampling techniques would most effectively sample the necrophilous insect community. However, because all four tested methods were deficient at sampling beetle species, future work should focus on optimizing the most promising methods, alone or in combinations, and incorporate hand-collections of beetles.

Aedes aegypti (L.; Diptera: Culicidae) has been established in the southwestern United States for several decades, but relationships between humans and mosquitoes in this arid region are not well-characterized. In August 2012, the outdoor premises of 355 houses within 20 neighborhoods in Tucson, Arizona were surveyed for containers that could provide larval habitat for Ae. aegypti mosquitoes. At the same time, a knowledge, attitudes and practices (KAP) questionnaire was administered to a resident of each house surveyed for immature mosquitoes. The KAP questionnaire assessed respondents' knowledge and concerns about vector-borne illnesses as well as practices they used to avoid mosquitoes. Of the houses surveyed, 91% had at least one container present, and 64% had at least one container with standing water. On average, each house had 2.2 containers with water at the time of the survey. The overall House Index (proportion of premises surveyed with at least one container with Ae. aegypti immatures present) was 13%. Based on questionnaire responses, there was a significant positive association between the number of residents in the home and the odds of finding Ae. aegypti positive containers on the premises, while household income showed a significant negative association. The reported frequency of checking for standing water was also significantly associated with the odds of finding immatures, although the nature of this association was ambiguous. Flower pots were the principal type of container with Ae. aegypti larvae. These findings show that larval habitat is widely available even in an arid environment and city with good housing and sanitation infrastructure.

Triatoma infestans Klug (Hemiptera: Reduviidae) is the main vector of Chagas disease in Latin America. This insect has been controlled with pyrethroids since the 1980s, although the emergence of resistance to deltamethrin has decreased control success in some areas of the Gran Chaco ecoregion. The response of T. infestans to deltamethrin was evaluated per developmental stage. In addition, we evaluated the possible stage-dependent expression of deltamethrin resistance. The bioassays were conducted by topical application of the insecticide in acetone. The drop size, age at the time of exposure, and mortality measuring time were standardized per stage. The lethal dose of deltamethrin moderately increased with the developmental stage. The resistance to deltamethrin was expressed in every instar, and was the highest in the fourth- and fifth-instar nymphs. While increasing, weight plays a relevant role in lethal dose stage dependency, a number of contributing factors such as degradative metabolism are probably involved in the variability of insecticide effect and resistance described for different T. infestans developmental stages. Possible explanations for these differences and their implications on resistance management and chemical control are discussed.

The culture filtrate of a plant pathogenic fungus that infects English ivy (Hedera helix L., Araliaceae) was investigated for mosquitocidal constituents by bioassay-guided isolation. The fungus responsible for pathogenic effects on the plant H. helix has been identified as Diaporthe eres Nitschke by molecular techniques. The mosquito adulticidal constituent in the culture filtrate was identified as 3,4-dihydro-8-hydroxy-3,5-dimethylisocoumarin (1) by spectroscopic techniques. Laboratory bioassays showed that (1) had larvicidal activity against permethrinsusceptible and -resistant Aedes aegypti strains. This compound was not active as an adulticide when tested by topical bioassay. Several analogs of (1) were synthesized and had better mosquitocidal activities than the naturally occurring (1) constituent.

Mutation of the voltage-gated sodium channel genes or knockdown resistance (kdr) and metabolic resistance in Aedes aegypti (L.) (Diptera: Culicidae) are important resistance mechanisms against pyrethroids.The present study investigated the effect of relaxation of deltamethrin selection pressure on the level of mixed-function oxidases (MFO), when the allele frequency of S989P+V1016G mutations is fixed in a resistant Ae. aegypti strain (UPK-R) from Chiang Mai,Thailand.The mosquitoes were divided into two groups, exposure and nonexposure groups, and maintained for 12 generations in an insectary room. Adults of the exposure group (F3 to F12) were treated with 0.05% deltamethrin-impregnated papers. The median lethal concentrations (LC₅₀) of deltamethrin of larvae were determined by World Health Organization (WHO) bioassay. MFO activity was determined in F0 and F12. The results revealed that there was a decreasing trend of adult mortality rates in the exposure group over time. The larval LC₅₀ values of the exposure group were gradually increased, whereas those of the nonexposure group were gradually decreased. The level of MFO activity in the nonexposure group (F12) was lower than the parent and exposure groups (F12) by 1.5 and 4-fold in the larvae, respectively, and 1.5 and 2.5-fold in the adult females, respectively. However, the frequency of P989+G1016 alleles in both groups was 100% up to F12 when the experiment ended. This study indicates that there was a significant but small reduction in the activity levels of MFOs when pyrethroid selection pressure is relaxed in this kdr strain of Ae. aegypti.

The lone star tick, Amblyomma americanum Linnaeus (Ixodida: Ixodidae), is emerging as an important human disease vector in the United States. While some recent studies have modeled broad-scale (regional or county-level) distribution patterns of A. americanum, less is known about how local-scale habitat characteristics drive A. americanum abundance. Such local-scale information is vital to identify targets for tick population control measures within land management units. We investigated how habitat features predict host-seeking A. americanum adult and nymph abundance within a 12-ha oak-hickory forest plot in the Missouri Ozarks. We trapped ticks using CO₂-baited traps at 40 evenly spaced locations for three 24-h periods during the summer of 2015, and we measured biotic and abiotic variables surrounding each location. Of 2,008 A. americanum captured, 1,009 were nymphs, and 999 were adults. We observed spatial heterogeneity in local tick abundance (min = 0 ticks, max = 112 ticks, mean = 16.7 ticks per trap night). Using generalized linear mixed models, we found that both nymphs and adults had greater abundance in valleys as well as on northern-facing aspects. Moreover, nymph abundance was negatively related to temperature variance, while adult abundance had a negative relationship with elevation. These results demonstrate that managers in this region may be able to predict local tick abundance through simple physiognomic factors and use these parameters for targeted management action.

Sand flies are very common in the region of Lençóis Maranhenses National Park, an important tourist attraction in Brazil. However, the role of some species and their relative importance locally in Leishmania Ross 1903 transmission is unclear. The objective of this study was to identify Leishmania infection in phlebotomine sand flies collected around the Lençóis Maranhenses National Park, an important conservation area and popular international/national tourist destination with a high incidence of leishmaniasis. Sand flies were collected in peridomiciliary areas on the tourist route from September 2012 to August 2013. The captured females were subjected to molecular analyses for the detection of Leishmania DNA. Sand flies were infected with four Leishmania species: Leishmania (Viannia) braziliensis (Vianna, 1911) was found in Lutzomyia whitmani (Antunes and Coutinho, 1939) (2.1%) and Lutzomyia longipalpis (Lutz and Neiva, 1912) (1.7%); Leishmania (Leishmania) infantum (Nicole, 1908) infected Lutzomyia wellcomei (Fraiha, Shaw, and Lainson, 1971) (20%), Lutzomyia sordellii (Shannon and Del Ponte, 1927) (4.3%), Lu. longipalpis (3.7%), and Lu. whitmani (0.8%); Leishmania (Leishmania) amazonensis (Lainson & Shaw, 1972) was found in Lu. whitmani (0.58%), while Leishmania (Viannia) lainsoni infected Lutzomyia evandroi (Costa Lima and Antunes, 1936) (3.4%), Lu. longipalpis (1.06%), and Lu. whitmani (0.29%). The occurrence of these parasites requires control measures to reduce the incidence of cutaneous leishmaniasis and to contain a possible epidemic of visceral leishmaniasis, the most severe form of the disease.

The San Joaquin kit fox (Vulpes macrotis mutica Merriam (Carnivora, Canidae)) is an endangered small carnivore endemic to the San Joaquin Valley of California. Commercial and agricultural land expansion has contributed to the lspecies' decline and invasion of more cosmopolitan species, providing means for potential ecological shifts in disease vector and host species. Fleas are common ectoparasites that can serve as important indicators of cross-species interactions and disease risk. We compared flea load and species composition on kit foxes inhabiting urban and nonurban habitats to determine how urbanization affects flea diversity and potential disease spillover from co-occurring species. We identified Echidnophaga gallinacea (Westwood) (Siphonaptera, Pulicidae) and Pulex spp. (L.) in both urban and nonurban populations, and Ctenocephalides felis (Bouche) (Siphonaptera, Pulicidae) only in the urban population. Flea load scores differed significantly across capture sites and with respect to concomitant sarcoptic mange infestation in the urban population, with milder flea infestations more typical of healthy foxes. All observed flea species are known vectors for pathogens that have been detected in mesocarnivores. Further examination of kit fox fleas and their associated pathogens will help to direct conservation and disease preventive measures for both wildlife and humans in the region.

Two species of mice, the white-footed mouse, Peromyscus leucopus (Rafinesque; Rodentia: Cricetidae) and the woodland deer mouse, Peromyscus maniculatus (Wagner; Rodentia: Cricetidae), serve as reservoirs of tick-borne pathogens in many parts of North America. However, the role P. maniculatus plays in the amplification and maintenance of Anaplasma phagocytophilum (Rickettsiales: Ehrlichiaceae) and Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) is not well understood. In northern Wisconsin, from 2012 to 2014, 560 unique mice were captured at 83 sites distributed across five forests. P. leucopus was more likely infested with immature Ixodes scapularis compared to P. maniculatus (60.1 vs. 28.3%). Abundance of immature I. scapularis on P. leucopus (M = 2.69; SD = 3.53) was surprisingly low and even lower for P. maniculatus (M = 0.717; SD = 1.44). Both P. leucopus and P. maniculatus were infected with B. burgdorferi, 24.0 and 16.8%, respectively. The prevalence of A. phagocytophilum infection in P. leucopus (1.69%) was similar to that observed in P. maniculatus (4.73%). Nine of 10 mice co-infected with both pathogens were P. maniculatus, and there were more co-infections in this species than expected by chance (3.07 vs. 0.82%). Differences in the behavior and biology between these two mice species may contribute to the variation observed in the abundance of host-attached ticks and pathogen prevalence. These differences highlight a potential hazard of the failure to differentiate between these visually similar mice, but there is evidence that these two mice species can each serve as reservoirs for tick-borne pathogens that cause human disease in Wisconsin.

Aedes aegypti (L.) and Aedes albopictus (Skuse) are known vectors of dengue, chikungunya, and other pathogens; however, their ecology and role in virus transmission has not been well studied in Pakistan. Here, we report on an intensive survey of potential breeding sites of Ae. aegypti in Rawalpindi, Punjab Province, Pakistan. The study continued for 11 mo and was divided into three seasons: January to June (pre-monsoon), July to September (monsoon), and October-November (post-monsoon). Larval mosquitoes were collected from all wet containers present in and around the houses. Altogether 5,570,418, 2,930,508, and 1,507,111 water-filled containers were examined during each season, of which 2,703, 8,843, and 3,439 were found positive for Ae. aegypti larvae or pupae, yielding Breteau indices of 0.46, 2.92, and 1.99%, respectively. Among 14 container types examined, the breeding preference ratio during all seasons was highest for roof-top water tanks and room evaporative coolers, followed by discarded tires and urban trash. The study concluded that increased urbanization, insufficient water supply and inefficient removal of urban trash resulted in increased numbers of nonbiodegradable containers around human dwellings, thereby creating ideal breeding habitats for Ae. aegypti. Measures such as integrated vector management, minimization of the breeding potential of Ae. aegypti by water management, proper disposal of discarded tires and urban trash, and health education were recommended for control of Ae. aegypti.

Lyme disease is an emerging public health threat in Canada. In this context, rapid detection of new risk areas is essential for timely application of prevention and control measures. In Canada, information on Lyme disease risk is collected through three surveillance activities: active tick surveillance, passive tick surveillance, and reported human cases. However, each method has shortcomings that limit its ability to rapidly and reliably identify new risk areas. We investigated the relationships between risk signals provided by human cases, passive and active tick surveillance to assess the performance of tick surveillance for early detection of emerging risk areas. We used regression models to investigate the relationships between the reported human cases, Ixodes scapularis (Say; Acari: Ixodidae) ticks collected on humans through passive surveillance and the density of nymphs collected by active surveillance from 2009 to 2014 in the province of Quebec. We then developed new risk indicators and validated their ability to discriminate risk levels used by provincial public health authorities. While there was a significant positive relationship between the risk signals provided all three surveillance methods, the strongest association was between passive tick surveillance and reported human cases. Passive tick submissions were a reasonable indicator of the abundance of ticks in the environment (sensitivity and specificity [Se and Sp] < 0.70), but were a much better indicator of municipalities with more than three human cases reported over 5 yr (Se = 0.88; Sp = 0.90). These results suggest that passive tick surveillance provides a timely and reliable signal of emerging risk areas for Lyme disease in Canada.

The biting behavior of anophelines is an important determinant of malaria transmission. Understanding the local vector host-seeking behavior, its outdoor/ indoor biting preference, and nocturnal biting periods is essential for effectively applying and improving vector control methods, such as Long Lasting Insecticidal Nets (LLINs) and personal protective measures. To better understand the biting and host-seeking patterns of Anopheles mosquitoes in Northwestern Burkina Faso, we performed biweekly Human Landing Catches (HLC) in six villages during the period of highest mosquito abundance and malaria transmission. We applied a negative binomial regression framework to statistically analyze the host-seeking activities of Anopheles species and test for differences across hours, months, and villages, as well as for differences between indoor and outdoor capture points. Anopheles gambiae s.l. was identified as the main malaria vector in this region, representing about 90% of the total anopheline population. Biting activity was significantly different across hours and showed a peaked plateau between 2000 and 0200 hours. Differences in the pattern of biting cycles were observed between the early and late rainy season. This study shows that anopheline biting activity in Northwest Burkina Faso is high throughout the night, at indoor and outdoor posts alike. Consequently, bed nets alone may not provide sufficient protection against early biting anophelines and should be complemented with additional strategies such as indoor residual spraying (IRS) and larval source management (LSM) to meet the WHO's ambitious goals that are reflected in the global technical malaria strategy for 2030.

Between May and June 2015, 512 bats, six rodents, and six tree-shrews were examined for ectoparasites in Vientiane and Khammouane Provinces, Laos. Thirty-seven ticks (33 females and four males) identified as Ixodes granulatus Supino were collected from four individuals of the Northern tree-shrew, Tupaia belangeri (Wagner) (Scandentia:Tupaiidae), and one female of Ixodes vespertilionis Koch was collected from one individual of the Intermediate Leaf-nosed Bat, Hipposideros larvatus (Horsfield) (Chiroptera:Hipposideridae). This appears to be the first record of I. vespertilionis from Laos, as well as the first record of this host–parasite relationship in the Southeast Asia region.

Cutaneous leishmaniasis is a vector-borne infection caused by flagellated parasitic protozoans in the genus Leishmania. Promastigotes are the infective stage, which are transmitted by the bite of female sand flies of the genera Phlebotomus or Lutzomyia. Three clinical forms of Leishmania infection are recognized in humans, and they are caused by different Leishmania species. They are cutaneous leishmaniasis (CL), mucocutaneous leishmaniasis (ML), and visceral leishmaniasis (VL). Up to 2 million cases of leishmaniasis are reported annually worldwide. In Pakistan, CL is widely distributed in endemic areas. In the current study, a survey was conducted to investigate the occurrence of CL in an endemic area of the metropolitan city of Multan, Pakistan. The material for diagnosis of CL was obtained from 461 patients from 239 clinical laboratories and health care centers in Multan. Of these patients, 42.9% (198 of 461) having positive findings of amastigotes in Giemsa stained tissue impression smears. The distribution of CL skin lesions was highly variable. Most patients (76.2%) had a single lesion. Most CL lesions were found on a single hand (23.7%). The prevalence of two CL lesions per patient was 21.7%, while three or more positive CL lesions were observed in 2.0% of patients. The 198 CL-positive patients ranged in age 10–40 yr old, 101 were males, and 97 were females. Logistic regression analysis of leishmaniasis versus age and gender showed that both the age and gender had a significant (P < 0.05) effect on the occurrence of infection. Outbreaks of CL were reported in 14 of the 68 Union Councils of Multan.

Haematophagous biting midges of the genus Culicoides are pests of humans, livestock, and wildlife, and some also serve as vectors of bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) worldwide. In North America, there are only two Culicoides spp. proven to transmit BTV and/or EHDV—Culicoides (Hoffmania) insignis Lutz (Diptera: Ceratopogonidae) and Culicoides (Monoculicoides) sonorensis Wirth and Jones (Diptera: Ceratopogonidae). Culicoides sonorensis is considered the primary vector due to its wide distribution across much of North America, whereas C. insignis has a neotropical distribution historically limited to peninsular Florida. However, Culicoides surveys conducted 2007 to 2015 have detected the presence of C. insignis in five southeastern states (Florida, Georgia, Alabama, Mississippi, and Louisiana), suggesting C. insignis has or is currently experiencing a northwestward range expansion in the southeastern United States. Because C. insignis has a neotropical distribution and is a known vector of BTV serotypes exotic to North America, an expanding range could pose an introduction risk of virus serotypes new to the region and/or increased transmission of circulating endemic serotypes.

Two species of the ixodid tick genus Dermacentor Koch, 1844 (Acari: Ixodidae) have previously been documented from Laos: D. auratus Supino, 1897 and D. steini (Schulze, 1933). Between 2012 and 2017, we recorded four additional Dermacentor species from this country: D. bellulus (Schulze, 1935); D. compactus Neumann, 1901; D. filippovae Apanaskevich & Apanaskevich, 2015; and D. tamokensisApanaskevich & Apanaskevich, 2016. In addition, seven specimens in the tick collection at the Institut Pasteur du Laos may represent new species and are currently under taxonomic investigation.

Aedes albopictus (Skuse) (Diptera: Culicidae) is a vector of several arboviruses impacting human health, including dengue, chikungunya, and potentially Zika. Vector control strategies that deploy modified males into the field are in use or under development and require a solid understanding of male biology; unfortunately, there has been limited effort to understand male Ae. albopictus reproductive biology, including sperm production and capacity. We tested whether body size and age affect spermatogenesis in Ae. albopictus. In general, older and larger males produced more sperm than their younger or smaller counterparts. Large males continued spermatogenesis well after 10-d post-eclosion (dpe), augmenting their reserves by 39%. By contrast, small males stopped producing sperm at 10 dpe. These results contribute to a deeper understanding of Ae. albopictus reproductive physiology. We discuss the usefulness of these findings in the context of Ae. albopictus life history and their utility in optimizing male mosquito release strategies.

Here, we analyze 248 DNA barcode sequences of 35 fly species of forensic importance in Brazil. DNA barcoding can be effectively used for specimen identification of these species, allowing the unambiguous identification of 31 species, an overall success rate of 88%. Our results show a high rate of success for molecular identification using DNA barcoding sequences and open new perspectives for immature species identification, a subject on which limited forensic investigations exist inTropical regions. We also address the implications of building a robust forensic DNA barcode database. A geographic bias is recognized for the COI dataset available for forensically important fly species in Brazil, with concentration of sequences from specimens collected mainly in sites located in the Cerrado, Mata Atlântica, and Pampa biomes.

West Nile virus (WNV) and Flanders virus (FLAV) co-occur in regions of North America. Because both viruses are maintained in a transmission cycle involving Culex mosquitoes and birds, screening mosquitoes for FLAV has been suggested as an enhancement to WNV surveillance and epidemic prediction. Using samples collected in 2010 and 2012 in Chicago, IL, USA, we demonstrate the presence of FLAV in four out of 287 (1.4%) Culex pools. We estimated minimum infection rates for WNV and FLAV to be 5.66 and 1.22 in 2010 and 8.74 and 0.61 in 2012, respectively. FLAV occurred 1 and 3 wk prior to the peak of WNV transmission in 2010 and 2012, respectively. FLAV sequences from Chicago were genetically diverse and phylogenetically representative of lineage A viruses from across the United States.