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1.
Rev Soc Bras Med Trop ; 53: e20190043, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31994655

RESUMO

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.


Assuntos
Aedes/classificação , Desenho de Equipamento , Controle de Mosquitos/instrumentação , Mosquitos Vetores/classificação , Animais , Controle de Mosquitos/métodos
2.
Malar J ; 18(1): 414, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823783

RESUMO

BACKGROUND: Many subsistence farmers in rural southeastern Tanzania regularly relocate to distant farms in river valleys to tend to crops for several weeks or months each year. While there, they live in makeshift semi-open structures, usually far from organized health systems and where insecticide-treated nets (ITNs) do not provide adequate protection. This study evaluated the potential of a recently developed technology, eave ribbons treated with the spatial repellent transfluthrin, for protecting migratory rice farmers in rural southeastern Tanzania against indoor-biting and outdoor-biting mosquitoes. METHODS: In the first test, eave ribbons (0.1 m × 24 m each) treated with 1.5% transfluthrin solution were compared to untreated ribbons in 24 randomly selected huts in three migratory communities over 48 nights. Host-seeking mosquitoes indoors and outdoors were monitored nightly (18.00-07.00 h) using CDC light traps and CO2-baited BG malaria traps, respectively. The second test compared efficacies of eave ribbons treated with 1.5% or 2.5% transfluthrin in 12 huts over 21 nights. Finally, 286 farmers were interviewed to assess perceptions about eave ribbons, and their willingness to pay for them. RESULTS: In the two experiments, when treated eave ribbons were applied, the reduction in indoor densities ranged from 56 to 77% for Anopheles arabiensis, 36 to 60% for Anopheles funestus, 72 to 84% for Culex, and 80 to 98% for Mansonia compared to untreated ribbons. Reduction in outdoor densities was 38 to 77% against An. arabiensis, 36 to 64% against An. funestus, 63 to 88% against Culex, and 47 to 98% against Mansonia. There was no difference in protection between the two transfluthrin doses. In the survey, 58% of participants perceived the ribbons to be effective in reducing mosquito bites. Ninety per cent were willing to pay for the ribbons, the majority of whom were willing to pay but less than US$2.17 (5000 TZS), one-third of the current prototype cost. CONCLUSIONS: Transfluthrin-treated eave ribbons can protect migratory rice farmers, living in semi-open makeshift houses in remote farms, against indoor-biting and outdoor-biting mosquitoes. The technology is acceptable to users and could potentially complement ITNs. Further studies should investigate durability and epidemiological impact of eave ribbons, and the opportunities for improving affordability to users.


Assuntos
Ciclopropanos , Fazendeiros , Fluorbenzenos , Mordeduras e Picadas de Insetos/prevenção & controle , Repelentes de Insetos , Malária/prevenção & controle , Controle de Mosquitos/instrumentação , População Rural , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Agricultura , Animais , Culicidae , Feminino , Habitação , Humanos , Pessoa de Meia-Idade , Tanzânia , Migrantes , Adulto Jovem
3.
Malar J ; 18(1): 412, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823793

RESUMO

BACKGROUND: The long-lasting insecticidal nets (LLIN) are effective against prevention of malaria and its utilization has been proven to save lives. Despite the mass distribution of LLIN, Nigeria remains the country with the highest malaria burden in Africa. The awareness of LLIN in Nigeria is high, but the utilization is low. The aim of this work is to describe factors associated with the utilization of LLIN among women of child-bearing age (WCBA) in Igabi, Kaduna, Nigeria. METHODS: A cross-sectional survey was conducted among 630 WCBA selected using a multi-stage sampling at 63 randomly selected villages in Igabi Local Government Area of Kaduna State. Trained female data collectors administered pre-tested structured questionnaires adapted from the Malaria Indicator Survey. Information collected were demographic profile, knowledge of LLIN as a preventive strategy for malaria, and LLIN ownership and utilization. LLIN utilization was assessed by identifying household members that slept under the hanged LLIN the night before the survey. Questions on the awareness of LLIN, ability to define what it is, use of LLIN, what differentiates LLIN from other bed nets, and duration of use before replacement, were scored and categorized as good, average and poor knowledge of LLIN. RESULTS: A total of 629 WCBA was sampled, their mean age (± SD) was 29.3 (± 6.2) years, 22.0% were pregnant, 40.5% had no formal education, 41.1% were employed, and 47.7% lived in rural communities. Awareness and good knowledge about LLINs for the prevention of malaria was 96.0% and 24.0%, respectively. The proportion of women who slept under a LLIN the night before the survey (utilization) was 70.0% and slightly higher (74.0%) among pregnant WCBA. Women who lived in rural communities were more likely to utilize LLINs compared to their urban counterparts (OR 3.4; 95% CI 2.3-4.9). Younger women (aged < 30 years) were less likely to utilize LLINs compared to the older women (OR 0.7; 95% CI 0.5-0.9). CONCLUSIONS: The knowledge of LLIN among WCBA was poor, but LLIN utilization was moderate. Living in rural communities and older WCBA were significant characteristics associated with LLIN utilization. Strategies that will improve the utilization of LLIN among the young and urban WCBA should be the focus of the Malaria Elimination Programme (MEP).


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Mosquiteiros Tratados com Inseticida , Malária/prevenção & controle , Controle de Mosquitos/instrumentação , População Rural , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Nigéria , Gravidez , Inquéritos e Questionários , Adulto Jovem
4.
Malar J ; 18(1): 386, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31791336

RESUMO

BACKGROUND: Measuring human exposure to mosquito bites is a crucial component of vector-borne disease surveillance. For malaria vectors, the human landing catch (HLC) remains the gold standard for direct estimation of exposure. This method, however, is controversial since participants risk exposure to potentially infected mosquito bites. Recently an exposure-free mosquito electrocuting trap (MET) was developed to provide a safer alternative to the HLC. Early prototypes of the MET performed well in Tanzania but have yet to be tested in West Africa, where malaria vector species composition, ecology and behaviour are different. The performance of the MET relative to HLC for characterizing mosquito vector population dynamics and biting behaviour in Burkina Faso was evaluated. METHODS: A longitudinal study was initiated within 12 villages in Burkina Faso in October 2016. Host-seeking mosquitoes were sampled monthly using HLC and MET collections over 14 months. Collections were made at 4 households on each night, with METs deployed inside and outside at 2 houses, and HLC inside and outside at another two. Malaria vector abundance, species composition, sporozoite rate and location of biting (indoor versus outdoor) were recorded. RESULTS: In total, 41,800 mosquitoes were collected over 324 sampling nights, with the major malaria vector being Anopheles gambiae sensu lato (s.l.) complex. Overall the MET caught fewer An. gambiae s.l. than the HLC (mean predicted number of 0.78 versus 1.82 indoors, and 1.05 versus 2.04 outdoors). However, MET collections gave a consistent representation of seasonal dynamics in vector populations, species composition, biting behaviour (location and time) and malaria infection rates relative to HLC. As the relative performance of the MET was somewhat higher in outdoor versus indoor settings, this trapping method slightly underestimated the proportion of bites preventable by LLINs compared to the HLC (MET = 82.08%; HLC = 87.19%). CONCLUSIONS: The MET collected proportionately fewer mosquitoes than the HLC. However, estimates of An. gambiae s.l. density in METs were highly correlated with HLC. Thus, although less sensitive, the MET is a safer alternative than the HLC. Its use is recommended particularly for sampling vectors in outdoor environments where it is most sensitive.


Assuntos
Anopheles , Controle de Mosquitos/instrumentação , Mosquitos Vetores , Animais , Burkina Faso , Feminino , Estudos Longitudinais , Malária
5.
Malar J ; 18(1): 417, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31831004

RESUMO

BACKGROUND: Mass and continuous distribution channels have significantly increased access to insecticide-treated nets (ITNs) in Ghana since 2000. Despite these gains, a large gap remains between ITN access and use. METHODS: A qualitative research study was carried out to explore the individual and contextual factors influencing ITN use among those with access in three sites in Ghana. Eighteen focus group discussions, and free listing and ranking activities were carried out with 174 participants; seven of those participants were selected for in-depth case study. Focus group discussions and case study interviews were audio-recorded, transcribed verbatim, and analysed thematically. RESULTS: ITN use, as described by study participants, was not binary; it varied throughout the night, across seasons, and over time. Heat was the most commonly cited barrier to consistent ITN use and contributed to low reported ITN use during the dry season. Barriers to ITN use throughout the year included skin irritation; lack of airflow in the sleeping space; and, in some cases, a lack of information on the connection between the use of ITNs and malaria prevention. Falling ill or losing a loved one to malaria was the most powerful motivator for consistent ITN use. Participants also discussed developing a habit of ITN use and the economic benefit of prevention over treatment as facilitating factors. Participants reported gender differences in ITN use, noting that men were more likely than women and children to stay outdoors late at night and more likely to sleep outdoors without an ITN. CONCLUSION: The study results suggest the greatest gains in ITN use among those with access could be made by promoting consistent use throughout the year among occasional and seasonal users. Opportunities for improving communication messages, such as increasing the time ITNs are aired before first use, as well as structural approaches to enhance the usability of ITNs in challenging contexts, such as promoting solutions for outdoor ITN use, were identified from this work. The information from this study can be used to inform social and behaviour change messaging and innovative approaches to closing the ITN use gap in Ghana.


Assuntos
Mosquiteiros Tratados com Inseticida/estatística & dados numéricos , Malária/prevenção & controle , Controle de Mosquitos/instrumentação , Adolescente , Adulto , Agentes Comunitários de Saúde , Feminino , Grupos Focais , Gana , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Controle de Mosquitos/métodos , Pesquisa Qualitativa , Inquéritos e Questionários , Adulto Jovem
6.
J Am Mosq Control Assoc ; 35(3): 178-185, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31647715

RESUMO

Mosquito surveillance in large urban areas of the southern USA that border Mexico has become increasingly important due to recent transmission of Zika virus and chikungunya virus in the Americas as well as the continued threat of dengue and West Nile viruses. The vectors of these viruses, Aedes aegypti, Ae. albopictus, and Culex quinquefasciatus, co-occur in residential areas, requiring vector control entities to deploy several different trap types, often expensive and labor-intensive, to surveil these ecologically different species. We evaluated the use of a single trap type, the US Centers for Disease Control and Prevention autocidal gravid ovitraps (AGOs), to monitor all 3 vector species across residential neighborhoods in San Antonio, TX, over 12 wk (epiweeks 24-35). Mosquito abundance was highest early in our surveillance period (epiweek 25) and was driven largely by Cx. quinquefasciatus. The AGOs collected significantly more Cx. quinquefasciatus than both Aedes species, with more Ae. aegypti collected than Ae. albopictus. The average number of Ae. aegypti captured per trap was consistent across most neighborhoods except for 2 areas where one had significantly the highest and the other with the lowest mosquitoes collected per trap. The average number of Ae. albopictus captured per trap varied with no clear pattern, and Cx. quinquefasciatus were trapped most often near forested hill country neighborhoods. These results indicate that AGOs are appropriate for detecting and tracking the relative abundance of Ae. aegypti, Ae. albopictus, and Cx. quinquefasciatus across a large and diverse urban landscape over time and therefore may be an inexpensive and streamlined option for vector surveillance programs in large cities.


Assuntos
Aedes/fisiologia , Culex/fisiologia , Controle de Mosquitos , Mosquitos Vetores/fisiologia , Animais , Feminino , Controle de Mosquitos/instrumentação , Densidade Demográfica , Texas
7.
Malar J ; 18(1): 335, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31570107

RESUMO

BACKGROUND: The decline in malaria cases and vectors is major milestone in fighting against malaria. The efficacy of MAGNet long-lasting insecticidal nets (MAGNet LLIN), an alpha-cypermethrin incorporated long-lasting net, with the target dose ± 25% of 5.8 g active ingredient (AI)/kg (4.35-7.25 g AI/kg) was evaluated in six veranda-trap experimental huts in Muheza, Tanzania against freely flying wild population of Anopheles funestus. METHODS: MAGNet LLINs were tested against wild, free-flying, host-seeking An. funestus mosquitoes over a period of 6 weeks (total of 36 nights in the huts). MAGNet LLIN efficacy was determined in terms of mosquito mortality, blood-feeding inhibition, deterrence, induced exiting, personal protection, and insecticidal killing over 20 washes according to WHO standardized procedures. Efficacy was compared with reference to a WHOPES recommended approved LLINs (DuraNet) and to a net conventionally treated (CTN) treated with alpha-cypermethrin at WHO-recommended dose and washed to just before cut-off point. The efficacy of MAGNet was evaluated in experimental huts against wild, free-flying, pyrethroid-resistant An. funestus. The WHO-susceptibility method was used to detect resistance in wild Anopheles exposed to 0.75% permethrin. Mosquito mortality, blood-feeding inhibition and personal protection were compared between untreated nets and standard LLINs. Blood-feeding rates were recorded and compared between the 20 times washed; blood-feeding rates between 20 times washed MAGNet LLIN and 20 times washed WHOPES-approved piperonyl butoxide (PBO)/pyrethroid were not statistically different (p > 0.05). RESULTS: The results have evidently shown that MAGNet LLIN provides similar blood-feeding inhibition, exophily, mortality, and deterrence to the standard approved LLIN, thus meeting the WHOPES criteria for blood feeding. The significantly high feeding inhibition and personal protection over pyrethroid-resistant An. funestus recorded by both unwashed and 20 times washed MAGNet compared to the unwashed DuraNet, the WHOPES-approved standard pyrethroid-only LLIN provides proof of MAGNet meeting Phase II WHOPES criteria for a LLIN. CONCLUSION: Based on this study, MAGNet has been shown to have a promising impact on protection when 20 times washed against a highly resistant population of An. funestus.


Assuntos
Anopheles , Mosquiteiros Tratados com Inseticida , Inseticidas , Lavanderia , Piretrinas , Animais , Habitação , Resistência a Inseticidas , Controle de Mosquitos/instrumentação , Tanzânia
8.
Malar J ; 18(1): 329, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31551076

RESUMO

BACKGROUND: Distribution campaigns for insecticide-treated nets (ITN) have increased the use of ITNs in Malawi, but malaria prevalence remains high even among those using the nets. Previous studies have addressed ITN ownership, insecticide resistance, and frequency of ITN use as possible contributing factors to the high prevalence of malaria infection despite high ITN coverage, but have rarely considered whether the condition of the ITN, or how many people use it, impacts efficacy. This study assessed how ITN integrity, ITN age, and the number of persons sharing a net might mitigate or reduce protective efficacy among self-identified ITN users in Malawi. METHODS: From 2012 to 2014, six cross-sectional surveys were conducted in both the rainy and dry seasons in southern Malawi. Data were collected on ITN use, integrity (number and size of holes), and age. Blood samples for detecting Plasmodium falciparum infection were obtained from reported ITN users over 6 months of age. Generalized linear mixed models were used to account for clustering at the household and community level. The final model controlled for gender, household eaves, and community-level infection prevalence during the rainy season. RESULTS: There were 9646 ITN users with blood samples across six surveys, 15% of whom tested positive for P. falciparum infection. Among children under 5 years old, there was a 50% increased odds of P. falciparum infection among those sleeping under an ITN older than two years, compared to those using an ITN less than 2 years old (OR = 1.50; 95% CI 1.07-2.08). ITN integrity and number of individuals sharing an ITN were not associated with P. falciparum infection. CONCLUSIONS: Older ITNs were associated with higher rates of P. falciparum in young children, which may indicate that insecticide concentrations play a larger role in infection prevention than the physical barrier of an ITN. ITN use was self-reported and the integrity measures lacked the precision of newer methods, suggesting a need for objective measures of ITN use and more precise assessment of ITN integrity.


Assuntos
Mosquiteiros Tratados com Inseticida , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Controle de Mosquitos/instrumentação , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Malaui/epidemiologia , Masculino , Plasmodium falciparum , Prevalência , Estações do Ano , Inquéritos e Questionários
9.
Parasit Vectors ; 12(1): 417, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31488182

RESUMO

BACKGROUND: Sterile male rear-and-release programmes are of growing interest for controlling Aedes aegypti, including use an "incompatible insect technique" (IIT) to suppress transmission of dengue, Zika, and other viruses. Under IIT, males infected with Wolbachia are released into the suppression area to induce cytoplasmic incompatibility in uninfected populations. These and similar mosquito-release programmes require cost-effective field surveys of both sexes to optimize the locations, timing, and quantity of releases. Unfortunately, traps that sample male Ae. aegypti effectively are expensive and usually require mains power. Recently, an electronic lure was developed that attracts males using a 484 Hz sinusoidal tone mimicking the female wingbeat frequencies, broadcast in a 120 s on/off cycle. When deployed in commercially available gravid Aedes traps (GATs), the new combination, sound-GAT (SGAT), captures both males and females effectively. Given its success, there is interest in optimizing SGAT to reduce cost and power usage while maximizing catch rates. METHODS: Options considered in this study included use of a smaller, lower-power microcontroller (Tiny) with either the original or a lower-cost speaker (lcS). A 30 s on/off cycle was tested in addition to the original 120 s cycle to minimize the potential that the longer cycle induced habituation. The original SGAT was compared against other traps incorporating the Tiny-based lures for mosquito capture in a large semi-field cage. The catch rates in waterproofed versions of this trap were then compared with catch rates in standard [BG-Sentinel 2 (BGS 2); Biogents AG, Regensburg, Germany] traps during an IIT field study in the Innisfail region of Queensland, Australia in 2017. RESULTS: The system with a low-power microcontroller and low-cost speaker playing a 30 s tone (Tiny-lcS-30s) caught the highest proportion of males. The mean proportions of males caught in a semi-field cage were not significantly different among the original design and the four low-power, low-cost versions of the SGAT. During the IIT field study, the waterproofed version of the highest-rated, Tiny-lcS-30s SGAT captured male Ae. aegypti at similar rates as co-located BGS-2 traps. CONCLUSIONS: Power- and cost-optimized, waterproofed versions of male Ae. aegypti acoustic lures in GATs are now available for field use in areas with sterile male mosquito rear-and-release programmes.


Assuntos
Aedes/fisiologia , Controle de Mosquitos/instrumentação , Controle de Mosquitos/métodos , Som , Viroses/prevenção & controle , Aedes/virologia , Animais , Custos e Análise de Custo , Dengue/prevenção & controle , Feminino , Masculino , Controle de Mosquitos/economia , Mosquitos Vetores/fisiologia , Mosquitos Vetores/virologia , Infecção por Zika virus/prevenção & controle , Infecção por Zika virus/transmissão
10.
Comput Math Methods Med ; 2019: 1923479, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31481976

RESUMO

In this paper, we will start off by introducing the classical Ross-Macdonald model for vector-borne diseases which we use to describe the transmission of dengue between humans and Aedes mosquitoes in Shah Alam, which is a city and the state capital of Selangor, Malaysia. We will focus on analysing the effect of using the Mosquito Home System (MHS), which is an example of an autodissemination trap, in reducing the number of dengue cases by changing the Ross-Macdonald model. By using the national dengue data from Malaysia, we are able to estimate λ, which represents the initial growth rate of the dengue epidemic, and this allows us to estimate the number of mosquitoes in Malaysia. A mathematical expression is also constructed which allows us to estimate the potential number of breeding sites of Aedes mosquitoes. By using the data available from the MHS trial carried out in Section 15 of Shah Alam, we included the potential effect of the MHS into the dengue model and thus modelled the impact MHS has on the spread of dengue within the trial area. We then extended our results to analyse the effect of the MHSs on reducing the number of dengue cases in the whole of Malaysia. A new model was constructed with a basic reproduction number, R 0,Mala MHS, which allows us to identify the required MHSs coverage needed to achieve extinction in Malaysia. Numerical simulations and tables of results were also produced to illustrate our results.


Assuntos
Dengue/prevenção & controle , Dengue/transmissão , Controle de Mosquitos/instrumentação , Aedes/virologia , Animais , Número Básico de Reprodução/estatística & dados numéricos , Cidades/epidemiologia , Simulação por Computador , Dengue/epidemiologia , Epidemias , Humanos , Malásia/epidemiologia , Conceitos Matemáticos , Modelos Biológicos , Controle de Mosquitos/estatística & dados numéricos , Mosquitos Vetores/virologia
11.
J Am Mosq Control Assoc ; 35(2): 107-112, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31442127

RESUMO

The World Health Organization (WHO) has recently recommended indoor residual spraying (IRS) as part of a vector control strategy to combat Aedes-borne diseases, including dengue, chikungunya, and Zika viruses. Hand compression sprayers have been used in malaria prevention and control programs worldwide since the 1950s and are a standard for IRS application. However, there are technological advances that should be considered to improve IRS application (e.g., flow-control valves, rechargeable-battery equipment, reduced-drift nozzles, etc.), particularly if interventions are performed in urban areas to target Aedes aegypti. Using WHO guidelines, we contrasted technical characteristics of potential IRS equipment including hand compression sprayers (Hudson X-pert, Goizper IK Vector Control Super), rechargeable-battery sprayers (Solo 416, Birchmeier REC 15ABZ, Hudson NeverPump), and motorized sprayers (Honda WJR 2525, Kawashima AK35GX). Measurements included flow rate, droplet size, battery/fuel life, and technical/physical characteristics. Flow rate, the most important parameter, of the Hudson X-pert was stabilized at 550 ml/min by the use of a control flow valve (CFV). The IK Vector Control Super had integrated CFVs and produced a similar flow as the Hudson X-pert. Rechargeable-battery equipment provided consistent flow as well as negligible noise. Motorized sprayers also produced consistent flow, but their weight, high noise pollution when used indoors, and high engine temperature made them highly unpleasant for technicians. We identify alternatives to the more traditional hand compression Hudson X-pert sprayer with technical and operational considerations for performing IRS.


Assuntos
Aedes , Habitação , Inseticidas , Controle de Mosquitos/instrumentação , Animais
12.
J Am Mosq Control Assoc ; 35(2): 123-134, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31442134

RESUMO

The aims of this review were to compare planning for both mosquito control and land use in east-central Florida, USA, and in New South Wales, Queensland, and the Northern Territory, Australia. Saltwater mosquito production in mangroves and salt marsh is the predominant mosquito control concern in all the areas. Urban encroachment towards saltwater mosquito habitats is a problem in both Florida and Australia. In east-central Florida and the Northern Territory, mosquito control is supported by comprehensive source reduction programs, whereas in Queensland and New South Wales, larviciding is the main method of control. The long-term control by source reduction programs reduces vulnerability to mosquito issues as population encroaches towards wetlands, whereas larviciding programs have to respond repeatedly as problems arise. Problems from urban encroachment are exacerbated if mosquito control and land-use planning are not integrated. Further, urban planning that is not informed by mosquito management can lead to increased mosquito problems by inadvertent design or allowing residential development close to mosquito habitats. This increases the need for mosquito control and related resourcing. At the regional level of governance, Florida and the Northern Territory generally have greater integration between planning for development and mosquito control than at the local government level in New South Wales and Queensland, where there is a lack of integration between mosquito agencies and planners. It is concluded that coordination of planning and mosquito control is more effective at higher government levels than at local levels, which have less connectivity between management areas and/or insufficient resources. The lesson is that collaboration can assist in avoiding or resolving conflicts.


Assuntos
Ecossistema , Controle de Mosquitos/métodos , Austrália , Florida , Controle de Mosquitos/instrumentação , Controle de Mosquitos/estatística & dados numéricos
13.
J Am Mosq Control Assoc ; 35(1): 67-70, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-31442185

RESUMO

Roof gutters on houses that have become inundated with leaf litter and cannot drain properly are an often-overlooked man-made container habitat that is suitable for mosquito larval development. In order to reduce the amount of leaf litter debris in gutters, many homeowners install debris screens, commonly referred to as "gutter guards," on their roof gutters, but no study has examined the effect of gutter guards on mosquito production. The objective of this research was to determine the extent to which different types of gutter guards affect mosquito colonization and abundance of juvenile mosquitoes in gutter habitats. Three experimental gutters, each with 1 of 3 treatments (control with no gutter guard, a metal lock-in mesh screen gutter guard, or a foam filter gutter insert), were placed at 5 field locations to monitor mosquito colonization and production over 8 wk. Pupae were collected daily, and eclosed adults were identified to species. Mosquitoes colonized and larvae developed in all gutters regardless of the presence of a guard, although those with the foam filter guards were least likely to be colonized (P < 0.001). Once colonized, the control gutters without a gutter guard had the lowest mosquito abundance (P < 0.001), and the metal lock-in gutters had the highest abundance (P < 0.001). The results suggest that if standing water exists in a gutter, gutter guards are not an effective tool for mosquito control.


Assuntos
Culicidae , Ecossistema , Habitação , Controle de Mosquitos , Animais , Culicidae/crescimento & desenvolvimento , Equipamentos e Provisões , Illinois , Larva/crescimento & desenvolvimento , Controle de Mosquitos/instrumentação
14.
J Am Mosq Control Assoc ; 35(1): 32-39, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-31442187

RESUMO

A series of field experiments was conducted in Florida, California, and Louisiana in order to investigate whether adding the Biogents® (BG)-Sweetscent lure to several commercially available mosquito traps increases their Aedes albopictus catch rates and to evaluate the BG-Mosquitaire trap with and without CO2. Adding the BG-Sweetscent to the SkeeterVac Bite-Guard SVE6211, MosClean UV LED (ultraviolet light-emitting diode), Flowtron® Galaxie PV 75, Dynatrap® DT2000XL, Bite Shield Protector, and Black Flag® BZ-40 increased their Ae. albopictus catch rates up to 4.2-fold. The catch rates of the BG-Mosquitaire and the BG-Sentinel did not differ significantly for Ae. aegypti and Culex quinquefasciatus. The BG-Mosquitaire without CO2 and only with BG-Sweetscent caught 1.2 times more Ae. albopictus than the CO2- and Lurex3-baited Mosquito Magnet® Patriot and 2.6 times more than the CO2- and Sweetscent-baited SkeeterVac, respectively. The BG-Mosquitaire baited with Sweetscent and CO2 collected 6.8 times more Ae. albopictus than the Mosquito Magnet Patriot and 11.9 times more than the SkeeterVac. We conclude that BG-Sweetscent increases the tiger mosquito catch rates of many commercially available mosquito traps. We proved that the BG-Mosquitaire is as efficient as the well-known BG-Sentinel and that it can outperform mosquito traps that are baited with propane-generated CO2.


Assuntos
Aedes , Dióxido de Carbono , Culex , Controle de Mosquitos , Mosquitos Vetores , Animais , California , Feminino , Florida , Louisiana , Masculino , Controle de Mosquitos/instrumentação , Controle de Mosquitos/métodos , Especificidade da Espécie
15.
Parasit Vectors ; 12(1): 418, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31455370

RESUMO

BACKGROUND: Improved surveillance techniques are required to accelerate efforts against major arthropod-borne diseases such as malaria, dengue, filariasis, Zika and yellow-fever. Light-emitting diodes (LEDs) are increasingly used in mosquito traps because they improve energy efficiency and battery longevity relative to incandescent bulbs. This study evaluated the efficacy of a new ultraviolet LED trap (Mosclean) against standard mosquito collection methods. METHODS: The study was conducted in controlled semi-field settings and in field conditions in rural south-eastern Tanzania. The Mosclean trap was compared to commonly used techniques, namely CDC-light traps, human landing catches (HLCs), BG-Sentinel traps and Suna traps. RESULTS: When simultaneously placed inside the same semi-field chamber, the Mosclean trap caught twice as many Anopheles arabiensis as the CDC-light trap, and equal numbers to HLCs. Similar results were obtained when traps were tested individually in the chambers. Under field settings, Mosclean traps caught equal numbers of An. arabiensis and twice as many Culex mosquitoes as CDC-light traps. It was also better at trapping malaria vectors compared to both Suna and BG-Sentinel traps, and was more efficient in collecting mosquitoes indoors than outdoors. The majority of An. arabiensis females caught by Mosclean traps were parous (63.6%) and inseminated (89.8%). In comparison, the females caught by CDC-light traps were 43.9% parous and 92.8% inseminated. CONCLUSIONS: The UV LED trap (Mosclean trap) was efficacious for sampling Anopheles and Culex mosquitoes. Its efficacy was comparable to and in some instances better than traps commonly used for vector surveillance. The Mosclean trap was more productive in sampling mosquitoes indoors compared to outdoors. The trap can be used indoors near human-occupied nets, or outdoors, in which case additional CO2 improves catches. We conclude that this trap may have potential for mosquito surveillance. However, we recommend additional field tests to validate these findings in multiple settings and to assess the potential of LEDs to attract non-target organisms, especially outdoors.


Assuntos
Anopheles/fisiologia , Culex/fisiologia , Controle de Mosquitos/instrumentação , Controle de Mosquitos/métodos , Raios Ultravioleta , Animais , Anopheles/efeitos da radiação , Culex/efeitos da radiação , Mosquitos Vetores , Tanzânia
16.
PLoS One ; 14(7): e0220563, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31365584

RESUMO

The BG-Malaria trap (BGM) is an adaptation of the well-known BG-Sentinel trap (BGS) with greater trapping efficiencies for anopheline and culicine mosquitoes. Its continued optimization requires greater understanding of mosquito flight behaviors near it. We used three high-resolution infrared cameras (68 frames/second) to track flight behaviors of laboratory-reared Anopheles arabiensis females in vicinity of the BGM in comparison with BGS. Additional comparisons were done for BGM at 20, 40 and 80cm heights, and for BGMs baited with Ifakara blend plus CO2, CO2 alone, or no bait. More mosquitoes were observed near BGM than BGS. Both BGMs installed 20cm above the floor and baited with CO2 received more visits by host-seeking mosquitoes than the other BGMs evaluated in their respective experiments. Trap designs, height and attractants all influence mosquito activity in vicinity of the traps which can be readily visualized using infrared cameras to accelerate trap development and testing. The greater activity of host-seeking mosquitoes near BGM than BGS supports the proven superiority of BGM traps in field and semi-field settings.


Assuntos
Comportamento Animal/efeitos dos fármacos , Voo Animal/fisiologia , Malária/prevenção & controle , Malária/parasitologia , Controle de Mosquitos/instrumentação , Controle de Mosquitos/métodos , Plasmodium falciparum/fisiologia , Animais , Anopheles , Feminino , Voo Animal/efeitos dos fármacos , Odorantes , Plasmodium falciparum/efeitos dos fármacos
17.
Parasit Vectors ; 12(1): 375, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358045

RESUMO

BACKGROUND: Insecticidal fabrics are important personal protective measures against mosquitoes, ticks and other disease vectors. In the absence of internationally accepted guidelines, bioefficacy tests have been carried out using continuous exposure and three minutes exposure bioassay methods. Recently, we have reported an improved method for bioefficacy testing of insecticidal fabrics, which involves continuous exposure of mosquitoes to the test fabrics. The present paper reports the comparative evaluation of the outcomes of the continuous exposure bioassay and the three minutes bioassay on the same fabric samples. METHODS: Permethrin content in the treated fabric samples was determined through HPLC analysis and NMR studies were performed to establish the stability of the analyte. Bioefficacy tests were carried out against dengue vector Aedes aegypti and malaria vector Anopheles stephensi as per the improved test method and the three minutes bioassay method. RESULTS: The permethrin doses in the fabric samples ranged from 60 to 3000 mg/m2 and 36.2% of permethrin was retained after 10 washings. The extraction and chromatographic analysis were not found to affect the stability of permethrin. In continuous exposure, all fabric samples showed bioefficacy, as the mean complete knockdown time for both Ae. aegypti (10.5-34.5 min) and An. stephensi (14.5-36.8 min) was ≤ 71.5 min. The same samples were found to be not effective when tested using the three minutes bioassay method, since the knockdown and mortality percentages were well below the required bioefficacy values. The bioefficacy of the fabric samples in terms of complete knockdown time was significantly higher against Ae. aegypti in comparison to An. stephensi. The mean complete knockdown time of Ae. aegypti increased to 48.3 min after 10 washings indicating a significant reduction in bioefficacy. CONCLUSIONS: Bioefficacy testing of the insecticidal fabrics using the improved method resulted in outcomes, which could be correlated better with the permethrin content in the fabric samples. The improved method is more appropriate for the testing of insecticidal fabrics than the three minutes bioassay method. Further evaluation of the improved method using different test arthropods could help in the formulation of specific guidelines for the bioefficacy testing of insecticidal fabrics.


Assuntos
Inseticidas , Controle de Mosquitos/métodos , Mosquitos Vetores , Permetrina , Têxteis/análise , Aedes , Animais , Bioensaio/instrumentação , Disponibilidade Biológica , Dengue/prevenção & controle , Inseticidas/normas , Malária/prevenção & controle , Controle de Mosquitos/instrumentação
18.
Am J Trop Med Hyg ; 101(2): 371-382, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31264562

RESUMO

Seasonal variation in the proportion of the population using an insecticide-treated net (ITN) is well documented and is widely believed to be dependent on mosquito abundance and heat, driven by rainfall and temperature. However, seasonal variation in ITN use has not been quantified controlling for ITN access. Demographic and Health Survey and Malaria Indicator Survey datasets, their georeferenced data, and public rainfall and climate layers were pooled for 21 countries. Nine rainfall typologies were developed from rainfall patterns in Köppen climate zones. For each typology, the odds of ITN use among individuals with access to an ITN within their households ("ITN use given access") were estimated for each month of the year, controlling for region, wealth quintile, residence, year, temperature, and malaria parasitemia level. Seasonality of ITN use given access was observed over all nine rainfall typologies and was most pronounced in arid climates and less pronounced where rainfall was relatively constant throughout the year. Peak ITN use occurred 1-3 months after peak rainfall and corresponded with peak malaria incidence and average malaria transmission season. The observed lags between peak rainfall and peak ITN use given access suggest that net use is triggered by mosquito density. In equatorial areas, ITN use is likely to be high year-round, given the presence of mosquitoes and an associated year-round perceived malaria risk. These results can be used to inform behavior change interventions to improve ITN use in specific times of the year and to inform geospatial models of the impact of ITNs on transmission.


Assuntos
Mosquiteiros Tratados com Inseticida/estatística & dados numéricos , Malária/prevenção & controle , Controle de Mosquitos/instrumentação , Estações do Ano , África/epidemiologia , Clima , Características da Família , Humanos , Incidência , Malária/epidemiologia , Chuva
19.
PLoS Negl Trop Dis ; 13(7): e0007538, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31344040

RESUMO

BACKGROUND: Public health responses to outbreaks of dengue, chikungunya, and Zika virus have been stymied by the inability to control the primary vector, Aedes aegypti mosquitos. Consequently, the need for novel approaches to Aedes vector control is urgent. Placement of three autocidal gravid ovitraps (AGO traps) in ~85% of homes in a community was previously shown to sustainably reduce the density of female Ae. aegypti by >80%. Following the introduction of chikungunya virus (CHIKV) to Puerto Rico, we conducted a seroprevalence survey to estimate the prevalence of CHIKV infection in communities with and without AGO traps and evaluate their effect on reducing CHIKV transmission. METHODS AND FINDINGS: Multivariate models that calculated adjusted prevalence ratios (aPR) showed that among 175 and 152 residents of communities with and without AGO traps, respectively, an estimated 26.1% and 43.8% had been infected with CHIKV (aPR = 0.50, 95% CI: 0.37-0.91). After stratification by time spent in their community, protection from CHIKV infection was strongest among residents who reported spending many or all weekly daytime hours in their community:10.3% seropositive in communities with AGO traps vs. 48.7% in communities without (PR = 0.21, 95% CI: 0.11-0.41). The age-adjusted rate of fever with arthralgia attributable to CHIKV infection was 58% (95% CI: 46-66%). The monthly number of CHIKV-infected mosquitos and symptomatic residents were diminished in communities with AGO traps compared to those without. CONCLUSIONS: These findings indicate that AGO traps are an effective tool that protects humans from infection with a virus transmitted by Ae. aegypti mosquitos. Future studies should evaluate their protective effectiveness in large, urban communities.


Assuntos
Aedes/virologia , Febre de Chikungunya/prevenção & controle , Controle de Mosquitos/instrumentação , Controle de Mosquitos/métodos , Mosquitos Vetores/virologia , Adolescente , Animais , Febre de Chikungunya/epidemiologia , Vírus Chikungunya , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Prevalência , Porto Rico/epidemiologia , Adulto Jovem
20.
Malar J ; 18(1): 224, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31272452

RESUMO

BACKGROUND: PermaNet® 3.0 is a deltamethrin-treated combination long-lasting insecticidal net with the addition of synergist piperonylbutoxide (PBO) on its roof section. It is designed to overcome the challenge posed by pyrethroid resistant vector populations against mainstream long-lasting insecticidal nets impregnated with pyrethroids only. The objective of this study was to determine insecticide resistance status of Anopheline and Culicine mosquitoes, to evaluate the bio-efficacy of PermaNet® 3.0 nets and to assess household factors affecting the physical integrity of PermaNet® 3.0 after 3 years of use. METHODS: Insecticide susceptibility test was conducted using the WHO tube test. Bio-activity of PermaNet® 3.0 samples was evaluated using the WHO cone bioassay. Cross-sectional survey was conducted on 150 randomly selected households from two districts to determine household factors affecting net utilization. One hundred fifty PermaNet® 3.0 nets were randomly collected from the community with replacement after 3 years of deployment and physical integrity of each net was assessed. RESULTS: Both Anopheles gambiae sensu lato and Culex quinquefasciatus developed resistance against permethrin and deltamethrin. However, following pre-exposure to synergist PBO the susceptibility of mosquito population increased to both permethrin (from 39% without to 92% with PBO against An. gambiae and from 28% without to 94% with PBO against Culex quinquefasciatus) and deltamethrin (from 52% without to 99% with PBO against An. gambiae and from 43% without to 98% with PBO against Culex quinquefasciatus). Eighty percent (80%) mortality was recorded in wild population of An. gambiae s.l. exposed to unused PermaNet® 3.0, but its bioactivity subsequently declined as washing frequency increased from 0 to 20. The PBO coated roof section of unused PermaNet® 3.0 resulted in higher mosquito mortality (100%) compared to the side panels without PBO (85%). House structure, cooking and washing habits, and damage due to household pests were cited as determinants associated with bed net deterioration. Bed net proportionate hole index (pHI) was ranged from 0 to 6064. Of the 150 PermaNet® 3.0 nets assessed 80, 29 and 41 were considered as 'good', 'acceptable' and 'too torn', respectively. CONCLUSIONS: The bio-efficacy evaluation of PermaNet® 3.0 from Jimma area, southwestern Ethiopia showed moderate efficacy against pyrethroid resistant population of An. gambiae and Culex quinquefasciatus. Thus, NMCPs in parallel to deployment of LLINs, should implement timely insecticide resistance management and integrated vector management strategies to slowdown the evolution and further spread of insecticide resistance. Household factors such as, housing conditions, open flame fire used for cooking and rodent attack were identified as factors contributing to the observed reduced bed net physical integrity in the study area. Universal coverage of bed nets should be accompanied with community awareness creation and training on net utilization and handling.


Assuntos
Anopheles/efeitos dos fármacos , Culex/efeitos dos fármacos , Resistência a Inseticidas , Mosquiteiros Tratados com Inseticida/estatística & dados numéricos , Controle de Mosquitos/instrumentação , Mosquitos Vetores/efeitos dos fármacos , Butóxido de Piperonila/farmacologia , Animais , Etiópia , Feminino , Inseticidas/farmacologia , Malária/prevenção & controle , Nitrilos/farmacologia , Permetrina/farmacologia , Piretrinas/farmacologia
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