Semi-field evaluation of electrocuting eave tubes for the control of endophagic mosquitoes in south-east Tanzania.

BACKGROUND: Eave spaces are major entry points through which malaria vectors enter houses. Interventions that target mosquitoes at the eaves have recently been developed. However, most of these interventions are based on insecticides for which resistance has been reported. Here we evaluated the efficacy of mosquito electrocuting eave tubes (MEETs) against Anopheles gambiae sensu stricto (An. gambiae s.s.) and Anopheles funestus s.s. under semi-field conditions. METHODS: Experiments were conducted in two semi-field chambers, each containing one experimental hut. Six electrocuting eave tubes were installed in each hut to assess their impact on laboratory-reared An. gambiae s.s. and An. funestus s.s.. Each species was assessed separately over 10 nights by releasing 200 unfed females per night into each chamber. One volunteer slept in each hut from 7 p.m. to 5 a.m. Mosquitoes were collected indoors and outdoors using mouth and Prokopack aspirators. RESULTS: The placement of MEETs significantly reduced the nightly An. gambiae s.s. indoor and outdoor biting, by 21.1% and 37.4%, respectively. Indoor-biting An. funestus s.s. were reduced by 87.5% while outdoor-biting numbers of An. funestus s.s. declined by 10.4%. CONCLUSIONS: MEETs represent a promising tool for controlling mosquitoes at the point of house entry. Further validation of their potential under natural field conditions is necessary. Several advantages over insecticide-based eave tubes are indicated and discussed in this article.

A Handheld Tool for the Rapid Morphological Identification of Mosquito Species (VectorCam) for Community-Based Malaria Vector Surveillance: Summative Usability Study.

BACKGROUND: Malaria impacts nearly 250 million individuals annually. Specifically, Uganda has one of the highest burdens, with 13 million cases and nearly 20,000 deaths. Controlling the spread of malaria relies on vector surveillance, a system where collected mosquitos are analyzed for vector species' density in rural areas to plan interventions accordingly. However, this relies on trained entomologists known as vector control officers (VCOs) who identify species via microscopy. The global shortage of entomologists and this time-intensive process cause significant reporting delays. VectorCam is a low-cost artificial intelligence-based tool that identifies a mosquito's species, sex, and abdomen status with a picture and sends these results electronically from surveillance sites to decision makers, thereby deskilling the process to village health teams (VHTs). OBJECTIVE: This study evaluates the usability of the VectorCam system among VHTs by assessing its efficiency, effectiveness, and satisfaction. METHODS: The VectorCam system has imaging hardware and a phone app designed to identify mosquito species. Two users are needed: (1) an imager to capture images of mosquitos using the app and (2) a loader to load and unload mosquitos from the hardware. Critical success tasks for both roles were identified, which VCOs used to train and certify VHTs. In the first testing phase (phase 1), a VCO and a VHT were paired to assume the role of an imager or a loader. Afterward, they swapped. In phase 2, two VHTs were paired, mimicking real use. The time taken to image each mosquito, critical errors, and System Usability Scale (SUS) scores were recorded for each participant. RESULTS: Overall, 14 male and 6 female VHT members aged 20 to 70 years were recruited, of which 12 (60%) participants had smartphone use experience. The average throughput values for phases 1 and 2 for the imager were 70 (SD 30.3) seconds and 56.1 (SD 22.9) seconds per mosquito, respectively, indicating a decrease in the length of time for imaging a tray of mosquitos. The loader's average throughput values for phases 1 and 2 were 50.0 and 55.7 seconds per mosquito, respectively, indicating a slight increase in time. In terms of effectiveness, the imager had 8% (6/80) critical errors and the loader had 13% (10/80) critical errors in phase 1. In phase 2, the imager (for VHT pairs) had 14% (11/80) critical errors and the loader (for VHT pairs) had 12% (19/160) critical errors. The average SUS score of the system was 70.25, indicating positive usability. A Kruskal-Wallis analysis demonstrated no significant difference in SUS (H value) scores between genders or users with and without smartphone use experience. CONCLUSIONS: VectorCam is a usable system for deskilling the in-field identification of mosquito specimens in rural Uganda. Upcoming design updates will address the concerns of users and observers.

Assessment of the USDA Biomass Harvest Trap (USDA-BHT) device as an insect harvest and mosquito surveillance tool.

Insects are a promising source of high-quality protein, and the insect farming industry will lead to higher sustainability when it overcomes scaling up, cost effectiveness, and automation. In contrast to insect farming (raising and breeding insects as livestock), wild insect harvesting (collecting agricultural insect pests), may constitute a simple sustainable animal protein supplementation strategy. For wild harvest to be successful sufficient insect biomass needs to be collected while simultaneously avoiding the collection of nontarget insects. We assessed the performance of the USDA Biomass Harvest Trap (USDA-BHT) device to collect flying insect biomass and as a mosquito surveillance tool. The USDA-BHT device was compared to other suction traps commonly used for mosquito surveillance (Centers for Disease Control and Prevention (CDC) light traps, Encephalitis virus surveillance traps, and Biogents Sentinel traps). The insect biomass harvested in the USDA-BHT was statistically higher than the one harvested in the other traps, however the mosquito collections between traps were not statistically significantly different. The USDA-BHT collected some beneficial insects, although it was observed that their collection was minimized at night. These findings coupled with the fact that sorting time to separate the mosquitoes from the other collected insects was significantly longer for the USDA-BHT, indicate that the use of this device for insect biomass collection conflicts with its use as an efficient mosquito surveillance tool. Nevertheless, the device efficiently collected insect biomass, and thus can be used to generate an alternative protein source for animal feed.

Upscaling the production of sterile male mosquitoes with an automated pupa sex sorter.

Effective mosquito population suppression has been repeatedly demonstrated in field trials through the release of male mosquitoes to induce sterile mating with wild females using the incompatible insect technique (IIT), the sterile insect technique (SIT), or their combination. However, upscaling these techniques requires a highly efficient and scalable approach for the sex separation of mass-reared mosquitoes to minimize the unintentional release of females, which can lead to either population replacement or biting nuisance, a major bottleneck up to now. Here, we report the successful development of an automated mosquito pupa sex sorter that can effectively separate large numbers of males from females for population suppression of Aedes aegypti, A. albopictus, and Culex quinquefasciatus. The male production capacity of the automated sex sorter was increased by ~17-fold compared with manual sex separation with the Fay-Morlan sorter and enabled one person to separate 16 million males per week. With ~0.5% female contamination, the produced males exhibited high flight ability and mating performance. The field trial demonstrates that the quality of A. albopictus males produced using the automated sex sorter is suitable for inducing population suppression. These results indicate that the automated sex sorter offers the potential to upscale IIT and SIT against mosquito vectors for disease control.

Large-scale performance assessment of the BG-Counter 2 used with two different mosquito traps.

BACKGROUND: Mosquitoes are important vectors of pathogens. They are usually collected with CO2-baited traps and subsequently identified by morphology. This procedure is very time-consuming. Automatic counting traps could facilitate timely evaluation of the local risk for mosquito-borne pathogen transmission or decision-making on vector control measures, but the counting accuracy of such devices has rarely been validated in the field. METHODS: The Biogents (BG)-Counter 2 automatically counts mosquitoes by discriminating the size of captured objects directly in the field and transmits the data to a cloud server. To assess the accuracy of this counting device, 27 traps were placed at 19 sampling sites across Germany and used in daily, weekly or bimonthly intervals from April until October 2021. The BG-Counter 2 was attached to a CO2-trap (BG-Pro trap = CO2-Pro) and the same trap was converted to also attract gravid mosquitoes (upside-down BG-Pro trap with a water container beneath = CO2-Pro-gravid). All captured mosquitoes were identified by morphology. The number of females (unfed and gravid), mosquito diversity and the number of identified specimens in relation to the counting data of the BG-Counter were compared between the two trapping devices to evaluate sampling success and counting accuracy. RESULTS: In total 26,714 mosquitoes were collected during 854 trap days. The CO2-Pro-gravid trap captured significantly more mosquitoes per trap day for all specimens, gravid females and non-gravid females, while there was no difference in the mosquito diversity. The linear model with the captured mosquitoes as a response and the counted specimens as a predictor explained only a small degree of the variation within the data (R2 = 0.16), but per individual trap the value could reach up to 0.62 (mean R2 = 0.23). The counting accuracy for the daily samples had a significant positive correlation with sample size, resulting in higher accuracy for the CO2-Pro-gravid trap and higher accuracy for sites and sampling months with high mosquito abundance. CONCLUSIONS: While the accuracy of the BG-Counter 2 is quite low, the device is able to depict mosquito phenology and provide information about local population dynamics.

Field comparison of broad-spectrum white LED-baited traps with narrow-spectrum green LED-baited traps in the capture of Anopheles mosquitoes (Diptera: Culicidae).

Light-Emitting Diodes (LEDs) have been effective light sources in attracting Anopheles mosquitoes, but the broad-spectrum white light, even with a wide-ranging application in lighting, have not been evaluated yet. In this study, the white light was field evaluated against the green one in the light trapping of anopheline mosquitoes by using two non-suction Silva traps and two CDC-type suction light traps. Anopheline mosquitoes were captured for two 21-night periods of collecting (2022 and 2023). In the first period, two LEDs were used per Silva trap, but three were used in the second one to increase the luminance/illuminance at traps. A CDC-type suction light trap equipped with an incandescent lamp was used in 2022 and a CDC-type suction light trap equipped with a 6 V-white light (higher luminance/illuminance) in 2023. A total of eight species and 3,289 specimens were captured in both periods. The most frequent species were Anopheles triannulatus s.l., An. goeldii, An. evansae and An. argyritarsis. In 2022, white LEDs were less attractive to anopheline mosquitoes than the other light sources, but without statistical difference among treatments (F = 2.703; P = 0.0752; df = 2). In 2023, even with an increased luminance/illuminance at traps, no statistical difference was found between the two LED-baited Silva traps (F = 6.690; P = 0.0024; df = 2), but rather between the 6 V-white-baited CDC-type suction light trap and green-baited Silva traps. Due to some drawbacks and the lower abundance of individuals caught by using white LEDs, the narrow-banded green LEDs is preferable to white ones for attracting anophelines.

Increased capture of Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae) by removing one ADULTRAP component

Abstract INTRODUCTION: Aedes aegypti is the main vector responsible for the transmission of numerous arboviruses. Adultrap® has been developed to catch these insects. METHODS: We tested the effectiveness of capturing adults with and without one of the components of Adultrap®. RESULTS: The mean number of insects caught by the original trap was 1.25 (standard deviation = 1.28), while the average obtained with the modified trap was 8.88 (standard deviation = 3.44). The medians were statistically different (p = 0.001) according to the Mann-Whitney test. CONCLUSIONS: The modification of Adultrap® increased the average catch of Ae. aegypti by up to seven times.

Análise dos domínios biotecnológicos empregados em patentes para combate ao mosquito Aedes aegypti, sob enfoque patentário / Analysis of the biotechnology domains used in patents to combat the Aedes aegypti mosquito, under patent protection approach

Objetivo: analisar os domínios biotecnológicos empregados ao combate do mosquito Aedes aegypti sob enfoque quantitativo patentário. Metodologia: o software Orbit Intelligence foi utilizado como banco de dados para prospecção das patentes empregando o termo "Aedes aegypti" como palavra-chave, a Classificação Internacional de Patentes (IPC) como filtro e biotecnologia como tecnologia dominante. Resultados e discussão: mostraram que o número de patentes biotecnológicas cresceu de forma significativa nos últimos vinte anos, sendo a grande maioria protegidas nos Estados unidos (US) e na Organização Mundial de Propriedade Intelectual (WO) pelo PCT. As seções mais frequentes no portfólio de patentes estão relacionadas às áreas de Química e Necessidades Humanas. Conclusão: biotecnologia foi a principal tecnologia dominante empregada em todas as patentes. O crescimento significativo do número de depósitos de patentes evidenciados nos resultados acima demonstra o interesse das empresas e centros de pesquisa

Field evaluation of sticky BR-OVT traps to collect culicids eggs and adult mosquitoes inside houses

Abstract INTRODUCTION: Culex quinquefasciatus is a mosquito of importance to public health, as it represents a real and/or potential risk for the transmission of pathogens to humans, such as some arthropod-borne viruses and nematodes that cause filariasis. In Brazil, three municipalities in the Metropolitan Region of Recife (RMR) that are endemic for lymphatic filariasis conducted control actions targeting this vector. With the goal of contributing novel C. quinquefasciatus collection strategies, a sticky trap capable of collecting eggs and imprisoning mosquitoes was investigated. METHODS: To evaluate the performance of the sticky BR-OVT trap, tests were carried out in the neighborhoods of Caixa d'Água and Passarinho (Olinda-PE-Brasil) between August 2011 and June 2012. Sixty traps were installed in the indoor areas of residences in the two districts. RESULTS: During the 11-month study, 0.52 [standard deviation (SD) = 1.52] Culex egg rafts, 2.16 (SD = 4.78) C. quinquefasciatus/trap/month, and 0.55 (SD = 1.28) Aedes/trap/month were caught. Female specimens predominated the traps (59% of C. quinquefasciatus and 96% of Aedes spp.). CONCLUSIONS The results demonstrated that the sticky BR-OVT trap is a useful tool for the collection of adult culicids of medical importance and offers an innovative way to collect C. quinquefasciatus eggs and adults in a single trap.

Efecto del tipo y del número de lavados en la eficacia de mosquiteros tratados con deltametrina de larga duración para el control de Aedes aegypti en Girardot, Colombia / Effect of the type and number of washes in the efficacy of long lasting insecticidal nets for Aedes aegypti control in Girardot, Colombia

Resumen Introducción. El uso de mosquiteros tratados con insecticida en fórmulas de larga duración ha demostrado resultados prometedores en el control de Aedes aegypti. Objetivo. Evaluar la eficacia de mosquiteros impregnados con deltametrina en una fórmula de larga duración para el control de A. aegypti en Girardot, Colombia, después de tres lavados. Materiales y métodos. Se hicieron bioensayos de eficacia de los mosquiteros contra A. aegypti silvestres después de utilizar los siguientes tres productos de lavado, siguiendo la metodología de la Organización Mundial de la Salud: detergente en polvo, detergente en polvo y blanqueador, y jabón de barra, todos utilizados hasta en 20 lavados. Resultados. El tipo de producto de lavado y el número de lavados afectaron significativamente la eficacia de los mosquiteros impregnados con deltametrina. El lavado con jabón de barra presentó el mayor efecto, pues en tan solo seis lavados la mortalidad bajó a 50 % (25/50), en contraste con 66 % (33/50 de mortalidad después del lavado con detergente en polvo y de 84 % (42/50) después del lavado con detergente y blanqueador. En cuanto al número de lavados, el jabón en barra también causó una mayor reducción de la eficacia: a 68 % con solo tres lavados. Conclusión. La eficacia de los mosquiteros impregnados con deltametrina de larga duración en el control de A. aegypti varió con el tipo de producto de lavado y el número de lavados, siendo el jabón en barra el que redujo su eficacia en mayor medida. Se requieren nuevos estudios para establecer la disminución en la concentración del insecticida entre lavados.

Abstract Introduction: The use of long lasting insecticidal materials has shown promising results in the control of Aedes aegypti. Objective: To evaluate the efficacy of long-lasting insecticidal nets (PermaNet®) for Aedes aegypti control after three washing treatments in the city of Girardot, Colombia. Materials and methods: Standard bioassays were conducted with the nets following the World Health Organization protocols using wild A. aegypti after three washing treatments: (1) Detergent powder, (2)detergent powder and bleach, and (3) bar soap, until completing 20 washes. Results: The type and number of wash treatments had a significant effect on net efficacy. Greater effects in the insecticide bioavailability were seen for the bar soap treatment. After six washes, mortality decreased by 50% (25/50), vs 66% (33/50) for the detergent powder and 84% (42/50) for the detergent powder and bleach treatments. Regarding the number of washes, the bar soap treatment reduced the efficacy to 68% after only three washes. Conclusion: The effectiveness of long-lasting insecticidal nets (PermaNet 2.0) for A. aegypti control varied in relation to the treatment and number of washes. The bar soap treatment resulted in the greatest reduction of mortality. Further studies on insecticidal reductions are needed under local conditions.

Bio-efficacy, physical integrity, community usage and washing practices of mosquito nets treated with ICON MAXX long-lasting insecticidal treatment in India

BACKGROUND New brands of potential long lasting insecticide nets (LLINs) and LLIN treatment kits require field evaluation before they are used in a vector control programme. OBJECTIVES The aim of this study was to evaluate the bio-efficacy, usage, washing practice and physical integrity of nets treated with LLIN treatment kit, ICON MAXX in a phase III field trial in Odisha state, India. METHODS A total of 300 polyester nets treated with ICON MAXX and 140 polyester nets treated conventionally with lambda-cyhalothrin CS 2.5% ITNs were distributed. The bio-efficacy was evaluated with WHO cone bioassay. The chemical analysis of netting pieces was done at the beginning, after 12 and 36 months of the trial. FINDINGS After one year of distribution of nets, the bioassay showed 100% mortality on both ITNs and ICON MAXX treated nets. At 36 months, the overall pass rate was 58.8% and the mean lambda-cyhalothrin content of LLINs was 34.5 mg ai/m2, showing a loss of 44.4% of the original concentration. CONCLUSION ICON MAXX treated LLIN was found to retain bio-efficacy causing 97% knockdown of Anopheles stephensi up to 30 months and met the WHOPES criteria. However, the desired bio-efficacy was not sustained up to 36 months.

Participación social en la prevención del dengue, zika y chikungunya: adaptación de la guía para el promotor

A fines del año 2015 y principios de 2016, la Argentina presenta una nueva epidemia de dengue, pero en esta oportunidad, con ciertas particularidades que la distinguen de situaciones epidémicas previas. La principal diferencia, que torna a la epidemia un fenómeno aún más grave y genera profunda preocupación en autoridades sanitarias, se debe a la coexistencia del dengue, con dos enfermedades virales, antes inexistentes en América Latina y el Caribe: el Zika y el Chikungunya. Ambas constituyen enfermedades virales transmitidas por el mismo vector que el dengue, el mosquito Aedes Aegypti; sin embargo, su potencial epidémico es muy alto, precisamente por tratarse de enfermedades emergentes en la Región, con una gran cantidad de población susceptible, nunca antes expuesta a este tipo de virus. Además, en el caso del Zika, la preocupación es aún mayor, dada la potencial asociación que tendría la infección por este virus en embarazadas, con la presencia de cierto tipo de malformaciones congénitas, particularmente la microcefalia. La figura del promotor comunitario cobra una singular importancia como agente catalizador de los cambios y la transformación social necesaria para la modificación de prácticas y hábitos de la comunidad: los promotores trabajan “con y para” la comunidad, buscando identificar sus principales problemas, necesidades y demandas pero también estimulando un mayor compromiso, involucramiento y participación de la propia comunidad en la solución a estos problemas. La presente guía busca fortalecer la participación de estos agentes en la actual epidemia de dengue, Zika y Chikungunya. Constituye una revisión y adaptación de una guía previa, elaborada y difundida por UNICEF, en conjunto con otras organizaciones gubernamentales y no gubernamentales, y que fue resultado de un intenso trabajo en equipo, interdisciplinario, intersectorial e interagencial...

Mass trapping with MosquiTRAPs does not reduce Aedes aegypti abundance

The objective of this study was to evaluate the effectiveness of Aedes aegypti mass trapping using the sticky trap MosquiTRAP (MQT) by performing a cluster randomised controlled trial in Manaus, state of Amazonas, Brazil. After an initial questionnaire and baseline monitoring of adult Ae. aegypti abundance with BG-Sentinel (BGS) traps in six clusters, three clusters were randomly assigned to the intervention arm where each participating household received three MQTs for mass trapping during 17 months. The remaining three clusters (control arm) did not receive traps. The effect of mass trapping on adult Ae. aegypti abundance was monitored fortnightly with BGS traps. During the last two months of the study, a serological survey was conducted. After the study, a second questionnaire was applied in the intervention arm. Entomological monitoring indicated that MQT mass trapping did not reduce adult Ae. aegypti abundance. The serological survey indicated that recent dengue infections were equally frequent in the intervention and the control arm. Most participants responded positively to questions concerning user satisfaction. According to the results, there is no evidence that mass trapping with MQTs can be used as a part of dengue control programs. The use of this sticky trap is only recommendable for dengue vector monitoring.

Insecticide-tretted bed nets in rondônia, Brazi: evaluation of their impact onn malaria control / Mosquiteiros impregnados com inseticida em Rondônia, Brasil: avaliação do impacto na incidência da malária

Mosquito nets treated with long-lasting insecticide (LLINs), when used in compliance with guidelines of the World Health Organization, may be effective for malaria vector control. In 2012, approximately 150,000 LLINs were installed in nine municipalities in the state of Rondônia. However, no studies have assessed their impact on the reduction of malaria incidence. This study analyzed secondary data of malaria incidence, in order to assess the impact of LLINs on the annual parasite incidence (API). The results showed no statistically significant differences in API one year after LLIN installation when compared to municipalities without LLINs. The adoption of measures for malaria vector control should be associated with epidemiological studies and evaluations of their use and efficiency, with the aim of offering convincing advantages that justify their implementation and limit malaria infection in the Amazon Region.

O uso de mosquiteiros impregnados com inseticida de longa duração (MILD), quando obedecidas as orientações da Organização Mundial da Saúde, é medida de controle de vetores da malária que pode apresentar excelentes resultados. Em 2012 foram instalados aproximadamente 150.000 MILDs em nove municípios do estado de Rondônia. Concomitantemente não houve estudo de avaliação de impacto na redução da incidência. O presente estudo analisou dados secundários da incidência, na expectativa de avaliar o impacto dos MILDs na incidência parasitária anual (IPA). Os resultados estatísticos mostram que, no período de um ano após a instalação dos MILDs, não houve diferença estatisticamente significativa na variação da IPA em relação a outros municípios que não receberam os MILDs. A adoção de medidas de controle vetorial deve ser acompanhada de estudos epidemiológicos e de avaliação de uso e eficácia para oferecer subsídios mais robustos que justifiquem a adoção desta medida de controle da malária na Região Amazônica.

Effectiveness of Mosquito Magnet® trap in rural areas in the southeastern tropical Atlantic Forest

Traps are widely employed for sampling and monitoring mosquito populations for surveillance, ecological and fauna studies. Considering the importance of assessing other technologies for sampling mosquitoes, we addressed the effectiveness of Mosquito Magnet® Independence (MMI) in comparison with those of the CDC trap with CO2 and Lurex3® (CDC-A) and the CDC light trap (CDC-LT). Field collections were performed in a rural area within the Atlantic Forest biome, southeastern state of São Paulo, Brazil. The MMI sampled 53.84% of the total number of mosquitoes, the CDC-A (26.43%) and CDC-LT (19.73%). Results of the Pearson chi-squared test (χ2) showed a positive association between CDC-LT and species of Culicini and Uranotaeniini tribes. Additionally, our results suggested a positive association between CDC-A and representatives of the Culicini and Aedini tribes, whereas the MMI was positively associated with the Mansoniini and Sabethini as well as with Anophelinae species. The MMI sampled a greater proportion (78.27%) of individuals of Anopheles than either the CDC-LT (0.82%) or the CDC-A traps (20.91%). Results of the present study showed that MMI performed better than CDC-LT or CDC-A in sampling mosquitoes in large numbers, medically important species and assessing diversity parameters in rural southeastern Atlantic Forest.

Evaluación de ovitrampas letales como estrategia para el control de Aedes aegypti / Evaluation of lethal ovitraps as a strategy for Aedes aegypti control

Introducción. El dengue es una enfermedad viral de transmisión vectorial de importancia en salud pública. La ausencia de una vacuna ha llevado a que las acciones de control se enfoquen principalmente en la disminución del mosquito vector. Sin embargo, estas estrategias tienen costos elevados. Las ovitrampas letales podrían contribuir de forma práctica en estrategias costo-efectivas para el control vectorial. Objetivo. Determinar el tipo de ovitrampas letales más eficiente para el control vectorial de Aedes aegypti , combinando diferentes tipos de insecticidas, sustrato de ovipostura e infusión atrayente. Materiales y métodos. El estudio se llevó a cabo en dos etapas. En la primera, se evaluaron en el laboratorio 18 ovitrampas diferentes provenientes de la combinación de insecticidas (deltametrina y permetrina), sustratos de ovipostura (toalla, dacrón y franela) e infusiones atrayentes (infusión de heno al 10 y 20 % y agua declorada). Para esta evaluación, las ovitrampas se colocaron en el interior de una jaula de evaluación y se liberaron 100 hembras grávidas de A. aegypti . Se seleccionaron las seis mejores ovitrampas con base en la mayor cantidad de oviposturas y en la menor emergencia larvaria. La segunda etapa consistió en evaluar las seis mejores ovitrampas en condiciones de campo. Resultados. Se observó una diferencia estadística entre las 18 ovitrampas en el laboratorio. Las que tenían deltametrina fueron las que presentaron los mejores resultados. En campo se observó que la ovitrampa más eficiente fue la compuesta por deltametrina, toalla e infusión de heno al 10 %. Conclusiones. La combinación de deltametrina, toalla y solución de heno al 10 % fue la más eficiente para la reducción vectorial de A. aegypti .

Introduction: Dengue fever is a vector-borne viral disease of major public health importance. In the absence of a vaccine, control measures are primarily focused on reducing the mosquito vector. However, these strategies are very expensive, and the use of lethal ovitraps could contribute, in a practical manner, to the design of cost-effective strategies for vector control. Objective: To determine the most efficient type of lethal ovitrap for Ae. aegypti vector control by combining different types of insecticides, oviposition substrates and attractant infusions. Materials and methods: The study was conducted in two stages. In the first, 18 different ovitraps resulting from the combination of insecticides (deltamethrin and permethrin), oviposition substrates (towel, dacron and flannel), and attractant infusion (10 and 20% hay infusion, and dechlorinated water) were evaluated in the laboratory. For this evaluation, ovitraps were placed into a mosquito holding cage, and 100 gravid Ae. aegypti females were released. The top six ovitraps were selected based on the higher number of registered eggs, and the lower hatched eggs percentage. In the second, the top six ovitraps were evaluated in field conditions. Results: In laboratory conditions, statistical differences were observed between the 18 ovitraps. The ovitraps with deltamethrin were the most efficient showing the best results. In field conditions, the ovitraps with the highest vector reduction were those combining deltamethrin/towel/10% hay infusion. Conclusions: The ovitrap combining deltamethrin, towel as oviposition substrate, and 10% hay infusion as attractant was the most efficient Ae. aegypti vector control.

Is there an efficient trap or collection method for sampling Anopheles darlingi and other malaria vectors that can describe the essential parameters affecting transmission dynamics as effectively as human landing catches? - A Review

Distribution, abundance, feeding behaviour, host preference, parity status and human-biting and infection rates are among the medical entomological parameters evaluated when determining the vector capacity of mosquito species. To evaluate these parameters, mosquitoes must be collected using an appropriate method. Malaria is primarily transmitted by anthropophilic and synanthropic anophelines. Thus, collection methods must result in the identification of the anthropophilic species and efficiently evaluate the parameters involved in malaria transmission dynamics. Consequently, human landing catches would be the most appropriate method if not for their inherent risk. The choice of alternative anopheline collection methods, such as traps, must consider their effectiveness in reproducing the efficiency of human attraction. Collection methods lure mosquitoes by using a mixture of olfactory, visual and thermal cues. Here, we reviewed, classified and compared the efficiency of anopheline collection methods, with an emphasis on Neotropical anthropophilic species, especially Anopheles darlingi, in distinct malaria epidemiological conditions in Brazil.

A comparison of larval, ovitrap and MosquiTRAP surveillance for Aedes (Stegomyia) aegypti

In Brazil, the entomological surveillance of Aedes (Stegomyia) aegypti is performed by government-mandated larval surveys. In this study, the sensitivities of an adult sticky trap and traditional surveillance methodologies were compared. The study was performed over a 12-week period in a residential neighbourhood of the municipality of Pedro Leopoldo, state of Minas Gerais, Brazil. An ovitrap and a MosquiTRAP were placed at opposite ends of each neighbourhood block (60 traps in total) and inspections were performed weekly. The study revealed significant correlations of moderate strength between the larval survey, ovitrap and MosquiTRAP measurements. A positive relationship was observed between temperature, adult capture measurements and egg collections, whereas precipitation and frequency of rainy days exhibited a negative relationship.

Comparison of automatic traps to capture mosquitoes (Diptera: Culicidae) in rural areas in the tropical Atlantic rainforest

In several countries, surveillance of insect vectors is accomplished with automatic traps. This study addressed the performance of Mosquito Magnet® Independence (MMI) in comparison with those of CDC with CO2 and lactic acid (CDC-A) and CDC light trap (CDC-LT). The collection sites were in a rural region located in a fragment of secondary tropical Atlantic rainforest, southeastern Brazil. Limatus durhami and Limatus flavisetosus were the dominant species in the MMI, whereas Ochlerotatus scapularis was most abundant in CDC-A. Culex ribeirensis and Culex sacchettae were dominant species in the CDC-LT. Comparisons among traps were based on diversity indices. Results from the diversity analyses showed that the MMI captured a higher abundance of mosquitoes and that the species richness estimated with it was higher than with CDC-LT. Contrasting, difference between MMI and CDC-A was not statistically significant. Consequently, the latter trap seems to be both an alternative for the MMI and complementary to it for ecological studies and entomological surveillance.

Diseño y evaluación de una ovitrampa para el monitoreo y control de Aedes aegypti, principal vector del dengue / Design and evaluation of a ovitrap for monitoring and control of Aedes aegypti, dengue fever vector

Objetivo. Diseñar y evaluar en condiciones de campo una ovitrampa con atrayentes químicos y un regulador de poblaciones para el monitoreo y control de los vectores del dengue. Material y métodos. A la ovitrampa CRISPP (OC) se le colocaron dos atrayentes químicos y una malla tricot sobre la superficie del agua. La efectividad de la OC fue evaluada y comparada contra una ovitrampa estándar (OE); además se determinó el efecto residual de los atrayentes. Resultados. Se contabilizaron un total de 7168 huevos; 4659 (65%) fueron puestos en la OC y 2509 (35%) en la OE; la emergencia de adultos en la OC fue 0% contra 93% en la OE, y el efecto residual fue de cuatro días. Conclusión. La OC atrajo un mayor número de huevos y controló a 100% de los adultos emergidos en comparación con la OE.

Objective. To design and evaluate in field conditions an ovitrap with chemical attractants and a population regulator for the monitoring and control of dengue vectors. Materials and methods. CRISPP ovitrap (OC) effectiveness was evaluated in comparison with a standard ovitrap (OE). A septum containing two chemical attractants and a mesh tricot on the surface of the water was collocated in the OC. The number of eggs in both ovitraps and the mortality of the emerged adults were counted. Also the residual effect was determined. Results. There were a total of 7168 eggs, 4659 (65%) were layed in the OC and 2509 (35%) in the OE and the emergence of adults in the OC was 0% compared with 93% in the OE. The residual effect was four days. Conclusions. The OC contained more eggs and caused minor emergency dengue vector adults in comparison with the OE.