Forensic entomology is an inferential science because postmortem interval estimates are based on the extrapolation of results obtained in field or laboratory settings. Although enormous gains in scientific understanding and methodological practice have been made in forensic entomology over the last few decades, a majority of the field studies we reviewed do not meet the standards for inference, which are 1) adequate replication, 2) independence of experimental units, and 3) experimental conditions that capture a representative range of natural variability. Using a mock case-study approach, we identify design flaws in field and lab experiments and suggest methodological solutions for increasing inference strength that can inform future casework. Suggestions for improving data reporting in future field studies are also proposed.

Lyme disease is the most commonly reported vector-borne disease in the United States, with the majority of cases occurring in the Northeast. It has now been three decades since the etiological agent of the disease in North America, the spirochete Borrelia burgdorferi, and its primary North American vectors, the ticks Ixodes scapularis Say and I. pacificus Cooley & Kohls, were identified. Great strides have been made in our understanding of the ecology of the vectors and disease agent, and this knowledge has been used to design a wide range of prevention and control strategies. However, despite these advances, the number of Lyme disease cases have steadily increased. In this article, we assess potential reasons for the continued lack of success in prevention and control of Lyme disease in the northeastern United States, and identify conceptual areas where additional knowledge could be used to improve Lyme disease prevention and control strategies. Some of these areas include: 1) identifying critical host infestation rates required to maintain enzootic transmission of B. burgdorferi, 2) understanding how habitat diversity and forest fragmentation impacts acarological risk of exposure to B. burgdorferi and the ability of interventions to reduce risk, 3) quantifying the epidemiological outcomes of interventions focusing on ticks or vertebrate reservoirs, and 4) refining knowledge of how human behavior influences Lyme disease risk and identifying barriers to the adoption of personal protective measures and environmental tick management.

Tunga bossii new species of tungid sand flea belonging to the caecata group is described with illustrations of the adult female, parasitizing the wild rodent Delomys dorsalis (Hensel) from Brazilian Atlantic Forest. Tunga bossii differs from the ten other known species of Tunginae by the size of the first segment of the maxillary palp and the presence of two bristles at the base of the maxilla. Tunga bossii also can be differentiated from other species of the T. caecata group by the eye morphology. A key to the adult species and neosomes of the genus Tunga also is included.

Mini-mark-release-recapture experiments were conducted in suburban Cairns, Australia to establish the sampling rate of the Biogents-Sentinel (BGS) trap for adult Aedes aegypti (L.). Small cohorts of marked mosquitoes (30 females and 15 males) were released at typical Cairns residences, and the number of marked mosquitoes recaptured in the BGS trap after 24 h was recorded. The sampling rate was compared between two seasons and two common housing styles (high-set ‘Queenslander-style’ timber and low-set brick houses), between old gravid and young nulliparous females, and between mosquitoes released in different areas of a house. Overall, the BGS traps recaptured a mean (±SEM) of 24.6% (±1.9) of the released marked female mosquitoes in 24 h. The mean recapture rate for females was significantly higher in the dry season (30.4% ± 2.8) compared with the wet (18.8% ± 2.2). The overall recapture rates did not differ significantly between the two house types, but variability between the individual premises was high. An overall mean of 18.2% (±1.7) of males was collected. Recapture rates of young nullipars and older gravid females were similar. These recapture rates can be used to estimate the population density of Ae. aegypti females in north Queensland, although it will provide an underestimate as trap sample was largely representative of mosquitoes present in the same area as the trap, and not from other areas of the house.

A mark-recapture project examined dispersal and flight distances of Culex mosquitoes from a wastewater treatment plant in Albany, NY, during 2007 and 2008. A self-marking device was constructed to mark egressing mosquitoes with fluorescent marking powder. Mosquitoes were recaptured using 30 CDC miniature light traps located within a 2.0 km radius of the marking site. A total of 13 and 10 marked Culex mosquitoes were recaptured in 2007 and 2008, respectively. Culex mosquitoes traveled a minimum of 0.16 km, a maximum of 1.98 km and, following correction for decreasing trap density with distance, had a mean distance traveled of 1.33 km. Characterizing the dispersal patterns of these mosquitoes is important for understanding the distribution of West Nile virus and other pathogens.

Aspects of phlebotomine behavior were investigated in the city of Campo Grande, Mato Grosso do Sul state. The insects were captured weekly during December 2003 to November 2005, with Centers for Disease Control light traps at seven different sites including forests and residential areas. In total, 11,024 specimens (7,805 males and 3,219 females) were collected, from which 9,963 (90.38%) were identified as Lutzomyia longipalpis, the proven vector of American visceral leishmaniasis agent. The remaining 9.62% comprised 21 species. L. longipalpis was the most frequent species in all sampled sites, and the first in the ranking of standardized species abundance index. In residential areas this species clearly predominated in the peridomicile (90.96%), in contrast to the intradomicile (9.04%); in animal shelters, it was more numerous in hen houses and prevailed at ground level, inside, and at forest edge around the residences; this aspect is worrying because this insect may remain sheltered in forested environments during the use of insecticides in homes. In the forest environment, other probable or proven vector of cutaneous leishmaniasis agents were also captured such as Lutzomyia whitmani (=Nyssomyia whitmani, sensu Galati), Lutzomyia antunesi (= Nyssomyia antunesi, sensu Galati), and Lutzomyia flaviscutellata (=Bichromomyia flaviscutellata, sensu Galati).

Adult numbers and sizes of mosquitoes were monitored for 2 yr in neighboring habitats on the western coast of Raiatea (Society Archipelago) in anticipation of testing new vector control technologies. Aedes polynesiensis Marks females comprised the overwhelming majority (≈99%) of the three species of mosquitoes captured in Biogent Sentinel traps placed at fixed sites on three small satellite islands (motus) of the western lagoon and on the shoreline of Raiatea. Aedes polynesiensis males, Aedes aegypti (L.), and Culex quinquefasciatus Say rarely were collected. Numbers of Ae. polynesiensis females per collection differed among trapping dates and locations, with the majority of females captured on two motus, Horea and Toamaro. Shoreline and Horea females had significantly longer mean wing lengths than females from Tiano and Toamaro. Thus, wing lengths were influenced more by local developmental conditions than overall numbers of adults. Significantly more females were captured during the wet season than the dry season. Nonetheless, at least on the two highly productive motus, dry-season females had larger wing lengths than their wet season counterparts. Local weather patterns predicted about half the variation in mosquito numbers. Differences in vector abundance observed when comparing neighboring motus are likely because of differences in human activity and mosquito suppression.

Understanding mosquito dispersal is critically important for vector-borne disease control and prevention. Mark—release—recapture methods using various marking techniques have made substantial contributions to the study of mosquito biology. However, the ability to mark naturally breeding mosquitoes noninvasively and with life-long retention has remained problematic. Here, we describe a method to mark naturally breeding mosquitoes with stable isotopes. Culex pipiens f. molestus mosquitoes were provisioned as larvae in laboratory experiments with ¹⁵N-labeled potassium nitrate and ¹³C-labeled glucose. Larval enrichment was sufficient to differentiate marked adult mosquitoes from unmarked control mosquitoes and the natural source population from Chicago Illinois, using either δ15N or δ13C. Isotopic retention lasted for at least 55 d for adult male and females mosquitoes. There were no consistent effects of isotopic enrichment on immature mosquito survival or adult mosquito body size. We then applied this marking technique to naturally breeding Culex pipiens mosquitoes in suburban Chicago, IL, and for the first time, report successful isotopic enrichment of mosquitoes in the field. This stable isotope marking technique will facilitate studies of mosquito dispersal.

Oviposition choice is a well-studied aspect of the mosquito life cycle, and offers a potential avenue for species-specific surveillance and control. In container inhabiting mosquitoes, there has been a focus on how the components of the aquatic media determine choice, with little work on the physical characteristics of the containers themselves. We performed five experiments examining the effect of physical container parameters on oviposition choice by Aedes albopictus. We examined containers of three different surface areas (small, 496 cm²; medium, 863 cm²; and large, 1,938 cm²) at the same water depth and the same or different heights in a series of binary choice assays. We also examined different depths with the same surface area in clear containers (where the depth may be perceived by the darkness of the water) and in opaque containers, which appear uniformly dark at different depths. We found a significant preference for medium containers over large containers, whether the containers were different or the same heights, and a trend toward a preference for small containers over medium containers. There was a preference for deeper water regardless of whether containers were clear or opaque. These behaviors suggest mosquitoes take into account physical aspects of their habitats and their oviposition choices are consistent with minimizing the risk of habitat drying.

The population genetic structure of Lutzomyia verrucarum (Townsend), a sand fly disease vector of Carrion's disease and cutaneous leishmaniasis in the Peruvian Andes, was characterized by sequencing 653 bp of cytochrome b and 1,125 bp of the NADH dehydrogenase subunit 4 genes of its mitochondrial genome. DNA sequence variation within and between valleys was compared in a sample of 220 sand flies from three valleys (Purisima, Huaylas, and Conchucos) and five departments (Amazonas, Cajamarca, Piura, Lima, and Huancavelica). Gene network and phylogenetic analyses indicated a high similarity of haplotypes collected within a single valley (0–0.52% nucleotide divergence). Flies from each valley had unique genotypes not shared with specimens from other valleys or from more distant regions (0.8–3.1% nucleotide divergence). Mountain ranges and geographic distance appear to have impeded migration (N_m=<0.18) between valleys and separated populations into discrete genetic units.

To track Aedes aegypti (L.) egg-laying behavior in the field in Iquitos, Peru, we developed methods for 1) sampling DNA from live mosquitoes and 2) high through-put parentage analysis using microsatellite markers. We were able to amplify DNA extracted from a single hind leg, but not from the pupal exuvia. Removal of a leg from teneral females caused no significant changes in female behavioral or life history traits (e.g., longevity, blood feeding frequency, fecundity, egg hatch rate, gonotrophic cycle length, or oviposition behavior). Using a panel of nine microsatellite markers and an exclusion-based software program, we matched offspring to parental pairs in 10 Ae. aegypti test families in which parents originated from natural development sites in Iquitos. By mating known individuals in the laboratory, retaining the male, sampling the female's DNA before release, and collecting offspring in the field, the technique we developed can be used to genotype large numbers of Ae. aegypti, reconstruct family relationships, and track the egg-laying behavior of individual Ae. aegypti in nature.

A better understanding of the visual attraction of house flies to colors and patterns is needed to improve fly trap performance. This study combined physiological responses measured with electroretinogram studies of the house fly's compound eyes and ocelli with behavioral attraction of flies to reflective colors and patterns in light tunnel assays. Compound eye and ocellar electroretinogram responses to reflected light were similar, with the largest responses to white and blue followed by yellow, red, green, and black. However, data from light tunnel behavioral assays showed that flies were attracted to white and blue light but were repelled by yellow. The addition of a black line pattern enhanced the attractiveness of blue visual targets, whereas yellow lines decreased attractiveness. Sensory input from the compound eye and the ocellus seems to be integrated to direct fly behavior. There is a direct correlation of house fly attractiveness to visual targets and the intensity of electrophysiological response, except for the yellow targets, which repel flies despite of intense electrophysiological response.

We conducted field trials to compare the relative repellent activity of two natural product compounds (nootkatone and carvacrol) with commercially available plant-derived (EcoSMART organic insect repellent) and permethrin-based (Repel Permanone) repellents against adult Ixodes scapularis Say and Amblyomma americanum (L.) (Acari: Ixodidae) by using treated coveralls. One day after treatment, nootkatone and carvacrol provided 100% repellency of I. scapularis adults, with nootkatone maintaining complete protection through 3 d, whereas carvacrol showed steadily declining repellency against I. scapularis during the 7-d course of the trials. Nootkatone was at least as effective against host-seeking A. americanum as against I. scapularis through 3 d. Carvacrol provided little protection against A. americanum adults. Roth natural compounds performed well initially in comparison with the commercial products. After 7 d, nootkatone was the most effective against both species followed in order of activity by Permanone, EcoSMART, and carvacrol. Nootkatone seems to have offer considerable potential as a clothing repellent against both I. scapularis and A. americanum.

The toxicity of pellitorine alone or in combination with (-)-asarinin, α-asarone, methyleugenol, or pentadecane (1:1, 1:2, 1:3, 2:1, and 3:1 ratios) to third instars from an insecticide-susceptible KS-CP strain and -resistant DJ-CP colony of Culex pipiens pallens Coquillett was evaluated using a direct-contact mortality bioassay. The binary mixture of pellitorine and (-)-asarinin (3:1 ratio) was significantly more toxic against KS-CP larvae (0.95 mg/liter) and DJ-CP larvae (1.07 mg/liter) than either pellitorine (2.08 mg/liter for KS-CP and 2.33 mg/liter for DJ-CP) or (-)-asarinin (11.45 and 12.61 mg/liter) alone. The toxicity of the other binary mixtures (1:1, 1:2, 1:3, and 2:1 ratios) and pellitorine did not differ significantly from each other. Based on the co-toxicity coefficient (CC) and synergistic factor (SF), the three binary mixtures (1:3, 2:1, and 3:1) operated synergistically (CC, 250–390 and SF, 1.4–2.2 for KS-CP; CC, 257–279 and SF, 1.1–2.1 for DJ-CP). The binary mixtures of pellitorine and (-)-asarinin merit further study as potential larvicides for the control of insecticide-resistant mosquito populations.

The host kairomones carbon dioxide (CO₂) and 1-octen-3-ol elicit a host seeking response in a wide range of haematophagous Diptera. This study investigates the response of Culicoides biting midges (Diptera: Ceratopogonidae) to these cues using field-based experiments at two sites in the United Kingdom with very different species complements. Traps used for surveillance (miniature CDC model 512) and control (Mosquito Magnet Pro) were modified to release ratios of (R)- and (S) -1-octen-3-ol enantiomers in combination with CO₂ and, in the case of the latter trap type, a thermal cue. Abundance and species diversity were then compared between these treatments and against collections made using a trap with a CO₂ lure only, in a Latin square design. In both habitats, results demonstrated that semiochemical lures containing a high proportion of the (R)-enantiomer consistently attracted a greater abundance of host-seeking Culicoides females than any other treatment. Culicoides collected using an optimal stimulus of 500 ml/min CO₂ combined with 4.1 mg/h (R)-1-octen-3-ol were then compared with those collected on sheep through the use of a drop trap. While preliminary in nature, this trial indicated Culicoides species complements are similar between collections made using the drop trap in comparison to the semiochemical-baited CDC trap, and that there are advantages in using (R)-1-octen-3-ol.

German cockroaches (Blattella germanica L.) have significant impacts on human health, most notably they are implicated as causes of childhood asthma. Gel bait formulations of fipronil, a phenylpyrazole insecticide, have been in use for German cockroach control in the United States since 1998. Previously, dieldrin resistant German cockroach strains were shown to have 7- to 17-fold cross-resistance to fipronil. More recently, a field-collected strain (GNV-R) displayed ≈36-fold resistance to topically applied fipronil at the LD₅₀ level, which is the highest level of fipronil resistance reported to date in the German cockroach. The aim of the current research was to identify mechanism (s) responsible for high-level fipronil resistance in the GNV-R strain. Synergist bioassays conducted using topical and injection application methods implicated cytochrome P450-mediated detoxification in resistance. Electrophysiological recordings using the suction-electrode technique revealed the nervous system of the GNV-R strain is insensitive to fipronil. In agreement with electrophysiology results, the alanine to serine (A302S) mutation encoded by the γ-amino butyric acid-gated chloride channel subunit gene resistance to dieldrin, which confers limited cross-resistance to fipronil, was detected in 95% of GNV-R strain individuals. Logistic regression analysis showed that A302S mutation frequency correlates with neurological insensitivity as shown by electrophysiology data. Overall, results of synergism bioassays, electrophysiological recordings, and A302S mutation frequency measurements suggest that fipronil resistance in the GNV-R strain is caused by the combined effects of enhanced metabolism by cytochrome P450s and target-site insensitivity caused by the A302S-encoding mutation in the resistance to dieldrin gene.

Culex pipiens quinquefasciatus Say fed blood containing 6.8 ± 0.3 logs (mean ± SE) plaque-forming units of West Nile virus (WNV)/ml were maintained at 28°C for incubation periods (IP) of 7, 14, or 21 d. Several attributes of vector competence were determined at each IP using quantitative real-time reverse transcriptase polymerase chain reaction to estimate plaque forming unit equivalents including: infection rate (WNV-positive abdomens), dissemination rate (WNV-positive legs or thoraces), combined dissemination rate (WNV-positive legs and thoraces), transmission rate (WNV-positive saliva), and WNV titers in abdomens, legs, thoraces, and saliva. Each rate increased or was equivalent with increasing IP. Mosquitoes transmitting WNV in saliva also had significantly higher IP-dependent WNV titers in abdomens, legs, and thoraces. Titers of WNV in abdomens were significantly correlated with titers in legs and thoraces, but the degree of association changed with IP. However, titers of abdomens, legs, and thoraces were not correlated with WNV presence or titer in the saliva. The results show that WNV presence or titer in the saliva of infected Cx. p. quinquefasciatus was not directly influenced by processes involved in WNV replication in other tissues. The processes controlling midgut infection and escape are, in part, independent from the infection processes in other tissues. The relationship between infection, dissemination, and transmission varied over time. The infection and replication of WNV in different tissues is likely influenced by different barriers encountered during the extrinsic incubation period. The significance of these observations for understanding vector competence is discussed.

Determining the bloodmeal hosts of the Culex vectors of encephalitis viruses such as West Nile virus is essential for understanding the role of these mosquitoes in enzootic and epidemic transmission. Although molecular techniques have increased our knowledge of blood feeding patterns by allowing host identification to the species level, few studies have focused on the role that sampling methods may play in determining these patterns. In the current study, we identified 644 bloodmeals from Culex tarsalis Coquillett and Culex quinquefasciatus Say females collected in CO₂ traps (dry ice-baited Center for Disease Control traps), in gravid traps, and aspirated from resting sites. There was no significant difference in the bloodmeal host apportionment in sampling methods such as gravid traps and resting collections that collected fully engorged females. However, CO₂ traps that collected partially fed females had a significantly different apportionment of hosts than either gravid or resting collections. Bloodied females from CO₂ traps had either fed on only a small subset of available host species or were biased toward more mammalian and fewer nonpasserine avian feeds than females from other collections. Because both full and partial bloodmeals can contribute to viral transmission, obtaining Culex bloodmeal collections from multiple sampling methods may be important to fully interpret the role of these mosquitoes as maintenance and/or bridge vectors.

Enterococcus faecalis is an important nosocomial pathogen and house flies have been implicated in the dissemination of this bacterium. In this study, GFP-expressing E. faecalis OG1RF:pMV158 was used to track the fate of the bacterium in the digestive tract of the house fly, Musca domestica (L.) to assess the vector potential of this insect for E. faecalis. Colony forming unit (CFU) counts were obtained from viable fluorescing E. faecalis recovered from mouthparts and digestive tract regions (labelum, foregut, midgut, and hindgut) at 1, 4, 8, 24, 48, 72, and 96 h after the bacterial exposure. Bacterial counts were significantly highest in the midgut at 1 h and 4 h and declined during the first 24 h. In the labelum, E. faecalis concentrations were low within the first 24 h and then greatly increased. Bacterial counts and direct observations of the digestive tract under a dissecting microscope with ultra violet light revealed that E. faecalis peaked in the crop after 48 h and remained high until the end of the experiment. Concentrations of E. faecalis in the hindgut were low when compared with other parts of the digestive tract. Microscopy and CFU counts suggest that E. faecalis was digested in the midgut but proliferated in the crop. Both drinking water and feed (flaked corn) sampled at the end of the assay (96 h) were contaminated by fluorescing E. faecalis, demonstrating that the flies disseminated E. faecalis. Our data support the notion that house flies can act as a bioenhanced vector for bacteria.

Tick-borne encephalitis virus (TBEV) is the causative agent of tick-borne encephalitis (TBE) and causes neurological disease in humans in Eurasia. TBEV is transmitted by ticks of the genus Ixodes. Currently 10,000–12,000 clinical cases are reported annually in ≈30 TBE endemic countries. Since 1990 the epidemiology of TBE is characterized by a global increase of clinical cases and an expansion of risk areas. Similar trends are also observed in Switzerland but few studies confirmed the emergence of new TBE foci by detecting viral RNA in field-collected ticks. In this study, free-living Ixodes ricinus (L.) ticks from one nonendemic and three new TBE endemic regions located in the Western part of Switzerland were screened during four consecutive years (2007–2010) for the presence of TBEV. A total of 9,868 I. ricinus ticks (6,665 nymphs and 3,203 adults) were examined in pools for TBEV by real-time reverse transcription polymerase chain reaction. Our results confirmed the presence of viral RNA in 0.1% (6/6120) of questing ticks collected in one new endemic region. Among TBE endemic sites, the minimal infection rate per 100 ticks tested ranged from 0.21 (1/477) to 0.95 (1/105). Four positive samples were sequenced and phylogenetic analysis of the NS5 gene showed that all TBEV nucleotide sequences belonged to the European subtype and were split into two distinct lineages originating probably independently from two distinct foci located North-East and East of the study region.

Little is known of the interactions between insect-only flaviviruses and other arboviruses in their mosquito hosts, or the potential public health significance of these associations. The specific aims of this study were to describe the geographic distribution, prevalence, and seasonal infection rates of Culex flavivirus (CxFV) and West Nile virus (WNV) in Culex quinquefasciatus Say in the Southeastern United States, investigate the potential association between CxFV and WNV prevalence in Cx. quinquefasciatus and describe the phylogenetic relationship among CxFV and WNV isolates from the Southeastern United States and around the world. Using ArboNET records, 11 locations were selected across Georgia, Mississippi, and Louisiana that represented a range of WNV human case incidence levels. Cx. quinquefasciatus were trapped weekly throughout the summer of 2009 and pools were screened for flavivirus RNA by reverse transcriptase polymerase chain reaction. Cx. quinquefasciatus from Georgia had significantly higher CxFV infection rates than either Mississippi or Louisiana. CxFV was not detected in Mississippi after July, and no CxFV was detected in Cx. quinquefasciatus in Louisiana. In Georgia, CxFV infection rates were variable between and within counties and over time. WNV infection rates were not significantly different across states or months, and WNV sequences from all three states were identical to each other in the envelope and NS5 gene regions. Phylogenetically, NS5 and E gene sequences from Georgia CxFV isolates clustered with CxFV from Japan, Iowa, and Texas. Multiple CxFV genetic variants were found circulating simultaneously in Georgia. No evidence was found supporting an association between WNV and CxFV infection prevalence in Cx. quinquefasciatus.

To investigate the possible spread of West Nile virus (WNV) into Japan, we carried out entomological surveillance for flaviviruses at migratory bird stopover sites in Hokkaido, Japan, during 2003–2006. A total of 3,826 mosquitoes, identified as 15 species in five genera, were collected and 2,465 of these were grouped into 123 pools that were assayed for cytopathic effects on mosquito and mammalian cell cultures and for flavivirus RNA by reverse transcription-polymerase chain reaction using flavivirus universal primer sets for fragments of the NS3 and NS5 genes. Neither WNV nor other mosquito-vertebrate transmitted flaviviruses were detected in mosquitoes collected at any of the sites in Hokkaido, but five Culex flaviviruses and one novel Aedes galloisi flavivirus were identified from Culex pipiens L. s. l. and Aedes galloisi Yamada, respectively. Genetic and phylogenetic analyses based on the partial NS5 nucleotide sequences classified Aedes galloisi flavivirus with the insect flavivirus, but distant from Cell fusing agent, Kamiti river virus, and Culex flaviviruses, showing <74% sequence identities. Polymerase chain reaction-based bloodmeal analysis of 79 females showed that all of the Aedes and Ochlerotatus mosquitoes fed on mammals (deer and humans), whereas, Cx. pipiens s. 1. mosquitoes fed on both of avian (ducks and sparrows, 85.7%) and mammalian hosts (dog, 14.3%). We suggest that to date WNV has not become established in Japan.

Two species of Microcerella Macquart were obtained from pig and llama corpses during a decomposition field experiment in highlands desert landscapes of Catamarca, Argentina. We sampled four pig and two llama carcasses. Microcerella antofagastensis sp. nov. is described, and M. quimaliensis (Lopes, 1982) is redescribed. Illustrations of male and female terminalia of both species are provided and should allow a correct identification. Notes on the biology of both species are given.

Genome size estimates for both sexes of forensically relevant Diptera from 17 species (four families) are reported herein. Average genome sizes ranged from 425.8 Mb for female Chrysomya rufifacies to 1,197.4 Mb for male Haematobia irritans. These estimates are useful not only for molecular studies, but also for determination of the species and sex of immatures. Species in three of the sampled families had sexually dimorphic genome sizes, presenting a new tool useful for the determination of sex in these species, especially in the immature stages where sexes are morphologically difficult or impossible to identify. In addition, closely related species had significantly different genome sizes, suggesting the use of flow cytometry as a new tool for species identification of some species of forensically relevant larvae.

Stable flies, Stomoxys calcitrans (L.), are among the most damaging arthropod pests of cattle worldwide. The last estimate of their economic impact on United States cattle production was published 20 yr ago and placed losses at $608 million. Subsequently, several studies of effects of stable flies on beef cattle weight gain and feed efficiency have been published, and stable flies have become increasingly recognized as pests of cattle on pasture and range. We analyzed published studies and developed yield-loss functions to relate stable fly infestation levels to cattle productivity, and then estimated the economic impact of stable flies on cattle production in the United States. Four industry sectors were considered: dairy, cow-calf, pastured stockers, and feeder cattle. In studies reporting stable fly infestation levels of individual herds, median annual per animal production losses were estimated to be 139 kg of milk for dairy cows, and 6, 26, and 9 kg body weight for preweanling calves, pastured stockers, and feeder cattle, respectively. The 200,000 stable flies emerging from an average sized winter hay feeding site reduce annual milk production of 50 dairy cows by an estimated 890 kg and weight gain of 50 preweanling calves, stockers, or feeder cattle by 58, 680, or 84 kg. In 2009 dollars, the value of these losses would be $254, $132, $1,279, or $154, respectively. Using cattle inventories and average prices for 2005–2009, and median monthly infestation levels, national losses are estimated to be $360 million for dairy cattle, $358 million for cow-calf herds, $1,268 million for pastured cattle, and $226 million for cattle on feed, for a total impact to U.S. cattle industries of $2,211 million per year. Excluded from these estimates are effects of stable flies on feed conversion efficiency, animal breeding success, and effects of infested cattle on pasture and water quality. Additional research on the effects of stable flies on high-production dairy cows and nursing beef calves is needed to increase the reliability of the estimates.

Quantifying the abundance of host-seeking fleas is critical for assessing risk of human exposure to flea-borne disease agents, including Yersinia pestis, the etiological agent of plague. Yet, reliable measures of the efficacy of existing host-seeking flea collection methods are lacking. In this study, we compare the efficacy of passive and active methods for the collection of host-seeking fleas in both the laboratory and human habitations in a plague-endemic region of northwest Uganda. In the laboratory, lighted “Kilonzo” flea traps modified with either blinking lights, the creation of shadows or the generation of carbon dioxide were less efficient at collecting Xenopsylla cheopis Rothchild and Ctenocephalides felis Bouché fleas than an active collection method using white cotton socks or cotton flannel. Passive collection using Kilonzo light traps in the laboratory collected significantly more X. cheopis than C. felis and active collection, using white socks and flannel, collected significantly more C. felis than X. cheopis. In field studies conducted in Uganda, Kilonzo traps using a flashlight were similar in their collection efficacy to Kilonzo traps using kerosene lamps. However, in contrast to laboratory studies, Kilonzo flea traps using flashlights collected a greater number of fleas than swabbing. Within human habitations in Uganda, Kilonzo traps were especially useful for collecting C. felis, the dominant species found in human habitations in this area.

The soft bodies and aquatic habitats of mosquito larvae pose a challenge for applying standard RNA-interference techniques to silence expression of target genes. Here we describe a novel technique for delivering double-stranded RNA into mosquito larvae by exploiting the larva's dehydration tolerance. Larvae were dehydrated in a NaCl solution and then rehydrated in water containing double-stranded RNA. Using larvae of Culex pipiens (L.) we demonstrated the principle by knocking down expression of the gene encoding heat shock protein 90. The knockdown persisted through the pupal stage and into adulthood, with a knockdown of ≈77% still evident on the third day of adult life. We anticipate that this relatively simple procedure will prove useful for knocking down expression of other genes as well, in larvae of this mosquito and in others.

During November 2010, three ticks were collected from three dogs living in the rural area of Arica, northern Chile. Morphological analyses of the ticks in the laboratory revealed that they were most similar to Amblyomma maculatum Koch and Amblyomma triste Koch. However, because of unique metatarsal spurs, neither of the Chilean specimens could be assigned with certainty to A. maculatum or A. triste, based on external morphology. The mitochondrial 16S rRNA gene partial sequences obtained from two Chilean specimens were 99.5% identical to A. triste from Uruguay, and 99.0% identical to A. maculatum from the United States. Through phylogenetic analysis inferred from partial 16S rBNA sequences, the Chilean specimens were classified as A. triste. Molecular analyses also showed that one of the three Chilean ticks was infected by Candidatus ‘Rickettsia andeanae’. These findings extend the geographical distribution of A. triste to Chile, where no tick-associated rickettsia had been reported previously.

Human biting catches of sylvatic yellow fever (SYF) vectors were conducted at eight stations in the influence area of the Manso hydroelectric power plant (Central Brazil) in sampling campaigns every 2 mo from July 2000 to November 2001. In total, 206 individuals were captured and classified as one of three species important for the transmission of SYF in Mato Grosso state: Haemagogus (Haemagogus) janthinomys (Dyar, 1921); Haemagogus (Conopostegus) leucocelaenus (Dyar & Shannon, 1924); and Sabethes (Sabethoides) chloropterus (Humboldt, 1819). The highest vector abundance was observed during the rainy season (November through March) and SYF vectors were present in all sampling points throughout the year, mainly in riparian and shadowed transitional forests at shadowed ramps.

The objective of this study was to evaluate the use of the trace element rubidium (Rb) as a long-lasting systemic biomarker for bloodfeeding females of the sand fly Phlebotomus papatasi Scopoli Baits containing Rb chloride were found to be palatable to hamsters in this study. We were able to detect Rb using a portable X-ray fluorescence analyzer in all sand flies that fed on Rb-treated hamsters for at least 14 d postbloodmeal. We also detected Rb in sand flies that took a bloodmeal from hamsters up to 10 d after the hamsters were withdrawn from a Rb-treated diet. Results of this study constitute proof of concept for the incorporation of Rb chloride into rodent baits for marking bloodfeeding sand flies, and suggest that Rb marking could be used as a technique for evaluating rodent-targeted sand fly control methods and in ecological studies on sand flies.

One genus, Ornithoica Rondani, and two species, Ornithoica momiyamai Kishida, and O. unicolor Speiser, are reported for the first time from the Republic of Korea. A total of six species, including two new records, of louse flies were collected from 78 birds belonging to 35 species from Seoul and Incheon Metropolitan Areas and Gyeonggi, Gangwon, Gyeongsangbuk, Jeollabuk, and Jeollanam Provinces, 2005–2010. An updated checklist of Korean hippoboscids consisting of seven genera (Hippobosca L., Icosta Speiser, Lipoptena Nitzsch, Ornithoica Rondani, Ornithoctona Speiser, Ornithomya Lattreille, and Ornithophila Rondani) and 11 species is presented, including hosts, collection records, and repositories.