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In 2022, the dramatic reduction of applied and extension urban entomology positions was highlighted and widely discussed by seasoned and nascent urban entomologists alike. In fact, many urban entomologists are calling for a “paradigm shift” within the discipline given the reduction in niche urban entomology-specific positions. Specifically, many individuals are insisting that movement toward a framework where urban entomologists address complex, cross-disciplinary issues and advocate for research funding through science policy is critical for the endurance of the discipline. In this new model, the purpose of urban entomology does not necessarily change, but rather expands to attack questions that may be of interest to the broader scientific community. In addition, this paradigm shift would necessitate increased engagement of urban entomologists with bureaucratic and administrative agencies to communicate the importance of urban pest management, especially in a landscape where funding opportunities and endowments have been reduced, reallocated, or eliminated. To reflect the ongoing transformation within the field of urban entomology, the objectives of this review were to highlight papers published in 2022 that exemplify the broader impacts of urban entomological studies and urban pest management. Studies with ties to global public health and Entomological Society of America science policy initiatives are highlighted to encourage urban entomologists to consider the far-reaching influence of their research.

Malaria is responsible for over 435,000 deaths annually, mostly occurring in sub-Saharan Africa. Detecting Plasmodiumspp. sporozoites (spzs) in the salivary glands of Anopheles(Diptera: Culicidae) vectors with circumsporozoite enzyme-linked immunosorbent assay (csELISA) is an important surveillance method. However, current technological advances are intellectual property and often require of distribution and highly trained users. The transition into paper-based rapid plataforms would allow for decentralization of survillance, especially in areas where it was virtually eliminated. The addition of bio-based materials have shown the potential to improve binding of target antigens, while being widely available. Here, we evaluate the use of chitosan and cellulose nanocrystals (CNC) as antibody carriers and substrate coatings on 96-well plates and on wax hydrophobized paper plates for the detection of Plasmodium falciparum(Pf), P. vivaxVK210 (Pv210), and P. vivax VK247(Pv247). To further improve the user-friendliness of the paper plates a quantitative photograph image-based color analysis was done. Interactions between the materials and the assay antibodies were studied by quartz crystal microbalance with dissipation monitoring (QCM-D). Overall, the addition of chitosan increased the interaction with antibodies and enhanced signaling in all tests. This work demonstrated that the adaptation of a PcsELISA shows potential as a cost-effective alternative assay platform easily adaptable in deployable testing sites that also showed reduction in reagent volumes by 80% and assay run time by seventh. While dipstick assays were previously developed, paper-based assays are a cost-effective and field-deployable alternative, reducing volumes of reagents that could be used in malaria control and elimination settings.

House fly (Musca domesticaL.) (Diptera: Muscidae) populations can negatively impact poultry layer facilities, posing a risk to human and animal health and egg food safety. House flies quickly develop resistance to traditional chemical control methods; therefore, improved biological control may provide opportunities for improved integrated pest management (IPM) programs. Biological control methods currently used include augmentative releases of pteromalid pupal parasitoids and application of the fungal entomopathogen Beauveria bassiana(Balsamo) Vuillemin. This study used bioassays to compare the impact of different B. bassianastrains on survival of house flies and of 3 species of filth fly parasitoids. The B. bassianathat were compared were 3 new field-collected isolates, an older field-collected isolate (L90), and a common commercially available strain (GHA). Flies and parasitoids were exposed to filter paper treated with 1.5 × 109spores of each strain and a control. All field-isolated strains induced lower mean survival times in house flies than GHA did. The results for all species of parasitoids demonstrated less difference among the treatment groups and the control than in-house flies. Although there was some effect of B. bassianaexposure on parasitoid mortality, the expected spatial separation of parasitoids from areas of application may offer some protection. Using the most effective tested strains of B. bassianaand filth fly parasitoids jointly could be a biological component of an IPM plan for fly control in poultry facilities.

Transgenesis has emerged as a powerful tool to control arthropod vectors and the diseases they transmit. Here, we highlight the latest developments on transgenic approaches in ticks, Anophelesand Aedesmosquitoes, based on recent findings and significant papers from 2022. We survey topics ranging from population replacement, population suppression, gene drive, sex ratio distortion, public engagement and capacity building, and gene editing in ticks. While presenting these advancements, we discuss the current challenges surrounding the application of arthropod transgenesis for the development of novel vector control strategies.

The field of veterinary entomology is primarily associated with the study of arthropods that impact the health of animals. Papers featured in the compilation of highlighted research from 2020 focused on studies conducted by scientists from the federal government that sought to understand and manage arthropods associated with wild and domesticated animals. The topics of these articles included research from the basic tenets of veterinary entomology: 1) biology and ecology of economically important pests, 2) novel control tactics and resistance management, 3) genomics, and 4) pathogen transmission. Key findings of the highlighted papers are presented and discussed to serve as a presentation record.

We report the presence of a male Haemaphysalis semermiscollected from the domestic cat, Felis catusin an aboriginal village located in Pahang, Malaysia. This paper constitutes a new host record of this tick species, and also the first documentation of the infestation of companion animals other than domestic dogs (Canis lupus) by H. semermisin Malaysia. Additionally, we have included an updated host index of the tick species in Southeast Asia.

The 2019 Entomological Society of America annual meeting was held in St. Louis, Missouri, just blocks away from the iconic Gateway Arch. Representing a ‘gateway to the West’, this inspired the theme of the Highlights in Medical Entomology to reflect on the accomplishments of the past year as we move into a ‘new frontier’ of vector biology research. Papers were selected broadly across arthropods that influence public health, focusing on topics ranging from West Nile virus transmission, ticks and tick-borne disease, to advances in genetics and ‘big data’ studies. This included current perspectives on West Nile virus ecology and epidemiology, which has now been endemic in the United States for 20 yr. Additional topics such as the advantages of citizen science and the importance of scientific communication were also discussed. Together, these papers demonstrate the achievements of the vector community while emphasizing the challenges that we collectively face to reduce the burden of vector-borne disease.

In this paper, we review the quill mite fauna of the family Syringophilidae Lavoipierre, 1953(Acariformes: Prostigmata) associated with New World and African parrots (Aves: Psittaciformes: Psittacidae), and describe eight new species including: Neoaulobia unsoeldiMarciniak-Musial & Sikora sp. nov. from the Burrowing Parakeet Cyanoliseus patagonusin Argentina; Lawrencipicobia ariniMarciniak-Musial & Sikora sp. nov. from the Black-headed Parrot Pionites melanocephalusin Surinam; L. araraunaMarciniak-Musial & Sikora sp. nov. from the Black-headed Parrot Ara araraunain Brazil; L. touitiMarciniak-Musial & Sikora sp. nov. from the Golden-tailed Parrotlet Touit surdusin Brazil; Rafapicobia valdivianaMarciniak-Musial & Sikora sp. nov. from the Burrowing Parrot Cyanoliseus patagonusin Brazil; R. pyrrhuraMarciniak-Musial & Sikora sp. nov. from the Green-cheeked Parakeet Pyrrhura molinaein Bolivia; R. xanthopterygiusMarciniak-Musial & Sikora sp. nov. from the Blue-winged Parrotlet Forpus xanthopterygiusin Brazil; and R. trainidadiMarciniak-Musial & Sikora sp. nov. from the Lilac-tailed Parrotlet Touit batavicusin Trinidad and Tobago. Additionally, we note fifteen new host species and many new locality records for the previously described taxa, and provide the keys for all species associated with psittaciform birds. Finally, we discuss the host–parasite relationships between syringophilid mites and parrots.

The mosquito-borne yellow fever virus (YFV) is the cause of a zoonotic disease, with both sylvatic and urban cycles. Some mosquito species have been associated directly with transmission of the virus in South America, although the importance given to each species varies depending on the bibliography, geographical location, or year of publication. For Argentina, few publications have assessed the involvement of mosquito species, especially those included in the sylvatic cycle. Therefore, the goal of our paper was to gather all the information available in South America and categorize all mosquito species potentially involved in the YFV transmission cycle in Argentina according to incriminating vector criteria. Based on three main characteristics (‘Hosts’, ‘Mosquito vector’, and ‘YF outbreak’), we generated scales of importance by species, one exclusively for Argentina and another for all of South America, Sabethes albiprivusTheobald, 1903 was the most important species in Argentina; whereas the most important species in South America were Haemagogus janthinomysDyar 1921, Hg. leucocelaenusDyar and Shannon, 1924, and Sa. chloropterusVon Humboldt, 1819. Our review highlights the lack of research that evaluates the importance of these species for YFV transmission in Argentina, while serving as a starting point to establish priorities for research on the bionomics and vector status of these species.

This paper deals with species A, C, D, and E of the Lindesayi Complex of Anophelessubgenus Anopheles(Diptera: Culicidae) that were recently recorded from Bhutan. Species B is not included due to insufficient data. Species A is Anopheles lindesayisensu stricto, and species C, D, and E are new species that are formally described and named herein as Anopheles drukiSomboon, Namgay & Harbach, Anopheles himalayensisSomboon, Namgay & Harbach and Anopheles thimphuensisSomboon, Namgay & Harbach, respectively. Morphological characteristics of the adults, larval and pupal stages of each species are provided and compared with An. lindesayifrom Bhutan.

The tick genus AmblyommaKoch, 1844 (Acari: Ixodidae) has received little attention in Malaysia; therefore, its associated hosts and distribution records are poorly known. In this study, we collected six Amblyommasp. individuals (two larvae and four adults) that infested a common treeshrew, Tupaia glis(Diard, 1820) (Scandentia: Tupaiidae) caught in a recreational area in Sungai Lembing, Pahang (West Malaysia). The adult female ticks were morphologically identified according to taxonomic keys prior to molecular identification using cytochrome oxidase subunit I (COI) and 16S rDNA genes. The ticks were genetically verified as Amblyomma geoemydae(Cantor, 1847) with 98%–99% similarity to the available GenBank sequences. Neighbor-joining (NJ) trees indicated that A. geoemydaewas clearly distinguished from other Amblyommaticks and this was supported with high bootstrap values. This paper is the first to report A. geoemydaeticks infesting T. glisand provides a new tick-host record from West Malaysia. This information is significant for further investigation, specifically on this tick species as potential vector of tick-borne disease (TBD) agents.

The aim of the present study was to explore resistance markers and possible biochemical resistance mechanisms in the Phlebotomine sand fly Phlebotomus papatasiin Esfahan Province, central Iran. Homogenous resistant strains of sand flies were obtained by exposing P. papatasicollected from Esfahan to a single diagnostic dose of DDT. The adults from the colony were tested with papers impregnated with four pyrethroid insecticides: Permethrin 0.75%, Deltamethrin 0.05%, Cyfluthrin 0.15%, and Lambdacyhalothrin 0.05% to determine levels of cross-resistance. To discover the presence of mutations, a 440 base pair fragment of the voltage gated sodium channel (VGSC) gene was amplified and sequenced in both directions for the susceptible and resistant colonies. We also assayed the amount of four enzymes that play a key role in insecticide detoxification in the resistant colonies. A resistance ratio (RR) of 2.52 folds was achieved during the selection of resistant strains. Sequence analysis revealed no knockdown resistance (kdr) mutations in the VGSCgene. Enzyme activity ratio of the resistant candidate and susceptible colonies were calculated for α-esterases (3.78), β-esterases (3.72), mixed function oxidases (MFO) (3.21), and glutathione-S-transferases (GST) (1.59). No cross-resistance to the four pyrethroids insecticides was observed in the DDT resistant colony. The absence of kdrmutations in the VGSCgene suggests that alterations in esterase and MFO enzymes are responsible for the resistant of P. papatasito DDT in central Iran. This information could have significant predictive utility in managing insecticide resistant in this Leishmaniavector.

The horn fly, Haematobia irritans irritans(L.) (Diptera: Muscidae), is an important bloodsucking ectoparasite of cattle throughout much of the world. The fly is mostly controlled using conventional synthetic insecticides but as concerns about resistance increase, alternative tactics have come under heightened scrutiny. Four desiccant dust products: Surround WP, a kaolin clay-based wettable powder; CimeXa, comprised of silica aerogel; Drione, silica aerogel + pyrethrins; and EcoVia, silica aerogel + thyme oil, were assessed for their lethal effects against horn fly eggs, larvae, pupae, and adults, under laboratory conditions. Although Surround WP and CimeXa did not prevent egg hatching and (when mixed with manure substrate) pupal development, the two products were associated with moderate reductions of emerged adults, and with complete adult contact mortality within 6 hr and 24 hr, respectively. Drione and EcoVia eliminated egg hatching, pupal development, and adults within 15 min to 1 hr, respectively, whether the flies were exposed to treated filter paper substrate or exposed by immersion in the dusts. Implications for horn fly control and advantages of inert desiccant dust formulations are discussed.

Successful monitoring of physiological resistance of malaria vectors requires about 150 female mosquitoes for a single set of tests. In some situations, the sampling effort is insufficient due to the low number of field-caught mosquitoes. To address this challenge, we demonstrate the feasibility of using the forced oviposition method for producing F1from field-caught Anophelesmosquitoes. A total of 430 and 598 gravid Anophelesfemales from four laboratory strains and five field populations, respectively, were tested. After blood feeding, gravid mosquitoes were individually introduced into transparent plastic vials, containing moistened cotton balls topped with a 4 cm2piece of filter paper. The number of eggs, hatching larvae, pupation, and adult emergence were recorded daily. The mean number of eggs per female mosquito ranged from 39.3 for Anopheles cracensto 93.6 for Anopheles dirusin the laboratory strains, and from 36.3 for Anopheles harrisonito 147.6 for Anopheles barbirostriss.l. in the field populations. A relatively high egg hatching rate was found in An. dirus(95.85%), Anopheles minimus(78.22%), and An. cracens(75.59%). Similarly, a relatively high pupation rate was found for almost all test species ranging from 66% for An. minimusto 98.7% for Anopheles maculatus, and lowest for An. harrisoni(43.9%). Highly successful adult emergence rate was observed among 85–100% of pupae that emerged in all tested mosquito populations. The in-tube forced oviposition method is a promising method for the production of sufficient F1progeny for molecular identification, vector competence, insecticide resistance, and bioassay studies.

Pest management professionals aim to answer two primary questions for their customers: 1) ‘Where/What is the pest?’ and 2) ‘How do I kill it?’. These two questions drive at the core of any pest management program. 2020 was an exciting year for entomology research, with much work being done on novel technologies and methods for detecting and controlling pests. The objectives of the current publication were to discuss papers published in 2020 that addressed the key pest management objectives of 1) monitoring and 2) controlling pest populations.

We conducted a baseline characterization of the abundance and seasonality of Aedes aegypti(Linnaeus, 1762)—a vector of dengue, chikungunya, and Zika—in two suburban localities of Yucatan, Mexico, as the first step in the implementation of an integrated vector management (IVM) plan combining ‘traditional Aedescontrol’ (source reduction/truck-mounted ultra-low volume [ULV] spraying) and incompatible insect technique/sterile insect technique for population suppression in Yucatan, Mexico. Weekly entomological collections with ovitraps and BG-sentinel traps were performed in 1-ha quadrants of both localities for 1 yr. Three distinct periods/phases were identified, closely associated with precipitation: 1) a phase of low population abundance during the dry season (weekly average of Aedeseggs per ovitrap and adults per BG trap = 15.51 ± 0.71 and 10.07 ± 0.88, respectively); 2) a phase of population growth and greatest abundance of Aedes(49.03 ± 1.48 eggs and 25.69 ± 1.31 adults) during the rainy season; and finally 3) a phase of decline among populations (20.91 ± 0.97 eggs and 3.24 ± 0.21 adults) after the peak of the rainy season. Seasonal abundance and dynamics of Ae. aegyptipopulations suggest that it is feasible to develop and implement time-specific actions as part of an IVM approach incorporating integrating novel technologies (such as rear-and-release of Wolbachia-infected males) with classic (insecticide-based) approaches implemented routinely for vector control. In agreement with the local vector control program, we propose a pilot IVM strategy structured in a preparation phase, an attack phase with traditional vector control, and a suppression phase with inundative releases, which are described in this paper.

From 2008 to 2017, the city of Abidjan, Côte d’Ivoire experienced several Aedes-borne disease epidemics which required control of the vector mosquito population based on the reduction of larval habitats and insecticidal sprays for adult mosquitoes. This study was undertaken to assess the insecticide susceptibility status of Aedes aegypti(Linnaeus) in the city of Abidjan. Immature Ae. aegyptiwere sampled from several larval habitats within seven communes of Abidjan and reared to adults. Three to five days old F1 emerged adults were tested for susceptibility using insecticide-impregnated papers and the synergist piperonyl butoxide (PBO) following WHO bioassay guidelines. The results showed that Ae. aegyptipopulations from Abidjan were resistant to 0.1% propoxur, and 1% fenitrothion, with mortality rates ranging from 0% to 54.2%. Reduced susceptibility (93.4–97.5% mortality) was observed to 0.05% deltamethrin, 0.75% permethrin, 0.05% lambda-cyhalothrin, 5% malathion, and 0.8% chlorpyrifos-methyl. This reduced susceptibility varied depending on the insecticide and the collection site. The restoration of mortality when the mosquitoes were pre-exposed to the synergist PBO suggests that increased activity of oxidases could be contributing to resistance. Three kdr mutations (V410L, V1016I, and F1534C) were present in populations tested, with low frequencies for the Leu410 (0.28) and Ile1016 (0.32) alleles and high frequencies for the Cys1534 allele (0.96). These findings will be used to inform future arbovirus vector control activities in Abidjan.

This study reports the first baseline information on tropical bed bug, Cimex hemipterus(F.) (Hemiptera: Cimicidae), infestations in Ghana. The purpose of this study was to assess bed bug infestation levels, and the efficacy of locally available insecticides and long-lasting insecticidal nets (LLINs) in controlling field bed bugs populations in the Cape Coast region. A survey was undertaken to assess bed bug infestation levels and current control practices by residents. In total, 205 bed bug affected households were identified in 20 communities and live bed bug infestations were associated with most of these premises. Many homeowners knew of other households (from 1 to 3) with a bed bug infestation. Residents reported itching and swelling of the skin from the bed bug bites and the bites were considered severe. The most common household bed bug control strategy was the application of insecticides. However, LLINs and commercially formulated insecticides commonly used by households (notably chloropyrifos and pyrethroid-based formulations) did not efficaciously suppress field collected strains of C. hemipterus. Using a dipping bioassay, mean mortality ranged from 0 to 60% for eggs, nymphs, and adults, and less than 40% mortality was observed in bed bugs placed on insecticide-treated filter paper. Each LLINs (all are pyrethroid based) produced a mean mortality of less than 20% in adult bed bugs. For a more effective response to the global bed bug resurgence in developing countries, government and supporting agencies need to render assistance to bed bug affected residents through the provision of improved pest management strategies.

Entomopathogenic fungi such as Beauveria bassiana(Balsamo) Vuillemin and Metarhizium anisopliae/brunneum(Metchnikoff)/Petch have shown promising results for managing the house fly, Musca domesticaL. A primary challenge of using these biological control agents (BCAs) in field situations is the time required to induce high adult house fly mortality, typically 6–7 d post-exposure. In this study, virulence of M. anisopliae(strain F52) and four B. bassianastrains were compared. The B. bassianastrains GHA and HF23 are used in commercial products and those were compared with two strains that were isolated from house flies on dairy farms (NFH10 and L90). Assays were conducted by exposing adult house flies to fungal-treated filter paper disks for 2 h. The lethal time to 50% mortality (LT50) at the high concentration of 1 × 109conidia ranged from 3.8 to 5.2 d for all five strains. GHA, NFH10, and L90 killed flies faster than M. anisopliaestrain F52; HF23 did not differ from either the M. anisopliaeor the other B. bassianastrains. Attempts with the NFH10 strain to induce faster fly mortality through selection across 10 fungal to fly passages did not result in shorter time to fly death of the selected strain compared with the unselected strain.

Madagascar has an important diversity of fleas (Siphonaptera), which almost species do not exist elsewhere. Scientists have provided huge efforts to improve knowledge on Malagasy fleas since the middle of 1900s particularly by investigating topics such as taxonomy, systematics, biogeography, and flea vector role. Since then, new species discovery has increased and currently, 48 species are recorded which the majority is endemic. Therefore, it becomes necessary to have updated keys to identify species membership. This paper presents morphological-based keys to identify at genus and species levels adult fleas reported as occurring in Madagascar. Illustrations are proposed to make easier the observation of morphological criteria, which may be tricky for sibling species.

The incidence of tick-borne diseases has increased in recent decades and accounts for the majority of vector-borne disease cases in temperate areas of Europe, North America, and Asia. This emergence has been attributed to multiple and interactive drivers including changes in climate, land use, abundance of key hosts, and people’s behaviors affecting the probability of human exposure to infected ticks. In this forum paper, we focus on how land use changes have shaped the eco-epidemiology of Ixodes scapularis-borne pathogens, in particular the Lyme disease spirochete Borrelia burgdorferisensu stricto in the eastern United States. We use this as a model system, addressing other tick-borne disease systems as needed to illustrate patterns or processes. We first examine how land use interacts with abiotic conditions (microclimate) and biotic factors (e.g., host community composition) to influence the enzootic hazard, measured as the density of host-seeking I. scapularisnymphs infected with B. burgdorferis.s. We then review the evidence of how specific landscape configuration, in particular forest fragmentation, influences the enzootic hazard and disease risk across spatial scales and urbanization levels. We emphasize the need for a dynamic understanding of landscapes based on tick and pathogen host movement and habitat use in relation to human resource provisioning. We propose a coupled natural-human systems framework for tick-borne diseases that accounts for the multiple interactions, nonlinearities and feedbacks in the system and conclude with a call for standardization of methodology and terminology to help integrate studies conducted at multiple scales.

In the search for new strategies to control Aedes aegyptiLinnaeus (Diptera: Culicidae), several studies have successfully related pyriproxyfen (PPF) tarsal transference to breeding sites (autodissemination), as well as the sterilization potential of females exposed to PPF. Potential PPF autodissemination by mosquito feces after the ingestion of sugar baits has also been proposed. Therefore, the present work evaluated several parameters, e.g., fecal production, residuality under dry and aqueous conditions, PPF excretion affecting emergence inhibition (EI) by fecal deposits of Ae. aegyptifed with attractive toxic sugar baits (ATSBs) containing PPF as well as their reproductive potential. Females were fed with ATSBs offered as droplets and the feces were collected using filter paper and transferred to plastic cups with L3 larvae to evaluate EI. The residual effect of feces in aqueous and dry conditions and PPF excretion on EI was obtained by keeping the feces in water or dried for different time intervals and using feces collected at 24-h intervals, respectively. Females received a bloodmeal after feeding on ATSBs, eggs and larval counting expressed the reproductive potential. The fecal mass was not affected by PPF concentration, but EI increased from 33 to 54% as the PPF concentration increased. The PPF excretion in the feces exceeded 96 h. The residual effect in the EI for feces kept in water was reduced by more than 60% after 30 d but was not affected under dry conditions. The fecundity and fertility of the females were reduced up to 51% and 97%, respectively.

The juvenile hormone analog S-methoprene is the only synthetic biopesticide that is registered with the United States Environmental Protection Agency to control arthropods of economic importance in public health, livestock, pets, urban, and stored products. The high activity, relative target specificity, and benign environmental profile of S-methoprene have been well documented. While the risk of resistance in mosquitoes to S-methoprene is generally low, there is a lack of information regarding cross resistance in S-methoprene-resistant mosquitoes to other pesticides. In this paper, a population of the southern house mosquito Culex quinquefasciatusSay from southern California acquired low levels of resistance to S-methoprene in the field, where the resistance ratios ranged 7.0- to 8.8-fold as compared with a laboratory reference colony. After 30 generations of laboratory selections by S-methoprene when resistance was elevated to 57.4- to 168.3-fold relative to an unselected population, various levels of cross resistance to other commonly used pesticides were revealed in the selected population. Cross resistance to the microbial mosquito larvicide Lysinibacillus sphaericus(Meyer & Neide) (Bacillales: Bacillaceae) was the most profound, amounting to 77.50- to 220.50-fold. The mechanism and potential management tactics toward cross resistance are discussed to preserve the unique value of this synthetic biopesticide.

Insecticide-impregnated traps and visual targets are used for tsetse (Diptera, Glossinidae) population control. Such devices are made with textiles and deltamethrin is frequently the insecticide of choice. However, persistence of an insecticide on textiles is affected by exposure to weather. Here we examine the effect of weathering on the capacity of four textiles with increasing proportions of polyester (0, 35, 65, and 100%) with cotton and viscose to retain deltamethrin. Textiles tested were those used to make visual targets in a pan-African program to maximize target efficiency for controlling tsetse vectors of African trypanosomiasis. Following impregnation in an aqueous suspension of deltamethrin at 1,000 mg/m2, textiles were weathered for 18 mo at Lambwe Valley, Kenya and sampled every 3 mo to make knockdown tests on the tsetse fly Glossina pallidipesAusten. Deltamethrin content of the textiles was established using gas chromatography mass-spectrometry at impregnation and after 9 mo of weathering. Textiles with higher proportions of polyester retained deltamethrin better: respectively, 100% polyester and 65:35 polyester/viscose textiles retained deltamethrin at 17 and 11 mg/m29-mo post-treatment that caused 100% knockdown in G. pallidipesafter 1 h, and killed 67 and 47% of flies, respectively, after 24 h. Eighteen-month weathered 100% polyester treated textile still knocked down all tsetse exposed to it within 2 h. The LD50for deltamethrin on filter paper for G. pallidipeswas estimated at 28.8 mg/m2, indicating that deltamethrin is more available on polyester to kill tsetse.Graphical Abstract

Contact irritant (locomotor excitation) and noncontact spatial repellent avoidance behavior to deltamethrin and cypermethrin at dosages 0.025, 0.05, and 0.1 g/m2impregnated on papers were evaluated in the laboratory against deltamethrin- and cypermethrin-resistant field populations of female Aedes aegypti(L.) from Rayong and Chanthaburi Provinces, Thailand. Pyrethroid-resistant populations were compared with a susceptible laboratory strain (NIH-Thai) using an ‘excito-repellency’ (ER) test system. Both NIH-Thai and field mosquitoes had stronger contact irritancy responses compared to the relatively weak noncontact repellency effects. Contact assays with deltamethrin and cypermethrin at 0.1 g/m2showed high escape rates for Rayong (80.1 and 83.4%, respectively) and Chanthaburi (84.6 and 73.1%, respectively) mosquitoes. Cypermethrin produced significantly different (P< 0.05) percent escape responses in contact tests between NIH-Thai and field mosquitoes. Only deltamethrin contact at 0.05 g/m2produced a significant escape response (P< 0.001) between NIH-Thai and Rayong mosquitoes. These results suggest that there may not be an overall significant effect of background pyrethroid resistance on escape response, and the differences by comparisons may reflect inherent individual variation when using the ER bioassay system. The results show that pyrethroid resistance in Ae. aegyptidoes not appear to influence or reduce contact avoidance responses with the compounds tested. In particular, deltamethrin at 0.1 g/m2was an effective contact irritant and toxic compound against pyrethroid-resistant populations of Ae. aegypti. Therefore, 0.1 g/m2deltamethrin could be considered for residual applications of either fixed surfaces or materials (e.g., curtains) as a supplemental control measure against adult dengue vectors.

In the 1930s, R. A. Cooley noted that Dermacentor occidentalis(Acarina: Ixodidae) and Dermacentor andersoniwere closely related and could hybridize. Decades later, James Oliver discovered that crosses of Dermacentor variabilis, D. andersoni,and D. occidentaliscould, on occasion, produce hybrids. A recent molecular analysis (both mtDNA and nDNA) in our laboratory revealed that certain specimens of Dermacentor andersoninested with Dermacentor parumapertus. Does this close relationship, along with the mito-nuclear discordance we have observed, mean D. andersoniand D. parumapertusare a single species? By contemporary taxonomic criteria, this seems improbable based on their distinctly different morphologies, host associations, and ecologies. This paper explores ideas related to mito-nuclear discordance, hybridization, and introgression (primarily) not only in these two species but also other members of the genus Dermacentor. Both D. andersoniand D. parumapertuscan be found on the same hosts and have sympatric distributions, so introgression of genetic material by occasional cross-mating between these two species is possible. Further, the difficulty in applying specific species concepts in ticks has been recently pointed out and a unified agreement on an integrative species concepts could clearly be useful in this situation. With the discovery of D. parumapertusas a potential vector of Rickettsia parkeriand the historically recognized role of D. andersoniin transmission of Rickettsia rickettsii, understanding the specific status of each lineage of these species (and others in the genus) is extremely important from a public health perspective.

The swallow bug, Oeciacus vicariusHorvath, is a hematophagous ectoparasite of the cliff swallow, Petrochelidon pyrrhonotaVieillot, and is closely related to bed bugs (Cimexspp.). Evolution of insecticide resistance has been documented for bed bugs but not studied in Oeciacus. For periods of 17 and 32 yr, two cliff swallow colonies in western Nebraska were treated during the summer breeding season using the organophosphate insecticide Dibrom. Despite continual treatments, O. vicariushas been observed frequently within these colonies. We evaluated the efficacy of Dibrom 8 on O. vicariusduring the 2016 season at two treated colonies and four that had never experienced treatment. Dibrom 8 was found to be effective in 100% of trials, with immobilization within minutes and death within 72 h, for individuals from all colonies. In control treatments (water), individuals collected from treated colonies exhibited greater survival than individuals from untreated colonies, and those from active colonies (bugs fed) had greater survival than those from inactive colonies (bugs unfed). A residual effect was observed in both lab and field trials: 100% mortality occurred in the lab after exposure to filter paper substrates treated both 5 and 10 d earlier, and in the field, nests treated once early in the season had O. vicariuscounts 43 d later that were <1% of those from untreated nests within the same colony. We hypothesize that the lack of resistance results from the limited potential for resistance allele fixation due to outbreeding and frequent immigration of insecticide-naïve individuals.