Background: This study aimed to investigate the relationship between the physicochemical characteristics of An. gambiae s.s.
View Article and Find Full Text PDFBackground: Long-lasting insecticidal bed nets (LLINs) are a key measure for preventing malaria and their evaluation is coordinated by the World Health Organization Pesticide Evaluation Scheme (WHOPES). LifeNet® was granted WHOPES time-limited interim recommendation in 2011 after successful Phase I and Phase II evaluations. Here, we evaluated the durability and community acceptance of LifeNet® in a Phase III trial from June 2014 to June 2017 in Benin rural area.
View Article and Find Full Text PDFBackground: The use of urban lowlands for agriculture contributes to the food security of city- dwellers, but promotes malaria transmission. The objective of the study was to characterize the entomological drivers of malaria transmission in two lowlands (N'Gattakro and Odiennekourani) in the city of Bouaké, Côte d'Ivoire.
Methods: The human landing catch technique was used to capture mosquitoes in houses located at the edge of two lowlands in Bouaké from February to December 2019.
Background: Previous studies have revealed high malaria transmission in Bouaké, Côte d'Ivoire. The sociopolitical crisis in the country and the resulting environmental changes have raised the need to update existing knowledge on mosquito vector species and malaria transmission.
Methods: Adult mosquitoes were caught using the human landing catch (HLC) sampling method in Bouaké.
Control of invasive species relies partly on permanent surveillance at international points of entry. We report the exceptional trapping of one adult mosquito (Diptera: Culicidae) in the port of Marseille, France, in July 2018, during a routine survey conducted according to International Health Regulations. Morphological and molecular identification classified the specimen as a female Aedes (Stegomyia) aegypti (L.
View Article and Find Full Text PDFMalaria control interventions target nocturnal feeding of the Anopheles vectors indoors to reduce parasite transmission. Mass deployment of insecticidal bed nets and indoor residual spraying with insecticides, however, may induce mosquitoes to blood-feed at places and at times when humans are not protected. These changes can set a ceiling to the efficacy of these control interventions, resulting in residual malaria transmission.
View Article and Find Full Text PDFStudies done in Bouaké (Côte d'Ivoire) about 20-yr ago reported that Anopheles gambiae s.l. Giles was the major malaria vector.
View Article and Find Full Text PDFBackground: Insecticide-based interventions have averted more than 500 million malaria cases since 2000, but insecticide resistance in mosquitoes could bring about a rebound in disease and mortality. This study investigated whether insecticide resistance was associated with increased incidence of clinical malaria.
Methods: In an area of southern Benin with insecticide resistance and high use of insecticide-treated nets (ITNs), malaria morbidity and insecticide resistance were measured simultaneously in 30 clusters (villages or collections of villages) multiple times over the course of 2 years.
Background: Scale-up of insecticide-based interventions has averted more than 500 million malaria cases since 2000. Increasing insecticide resistance could herald a rebound in disease and mortality. We aimed to investigate whether insecticide resistance was associated with loss of effectiveness of long-lasting insecticidal nets and increased malaria disease burden.
View Article and Find Full Text PDFA correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
View Article and Find Full Text PDFTo tackle the problem of insecticide resistance, all resistance mechanisms need to be studied. This study investigated the involvement of the cuticle in pyrethroid resistance in a strain of Anopheles gambiae, MRS, free of kdr mutations. Bioassays revealed MRS to be resistant to pyrethroids and DDT, indicated by increasing knockdown times and resistance ratios.
View Article and Find Full Text PDFChikungunya virus (CHIKV) transmission occurs through the bite of an infected Aedes mosquito which injects virus-containing saliva into the skin of the human host during blood feeding. In the present study, we have determined the effect of Aedes aegypti saliva on CHIKV replication in human skin fibroblasts, a major cell type for viral entry, which mimics the events that occur during natural transmission. A significant increase in the expression of viral transcripts and infectious viral particles was observed in fibroblasts infected with CHIKV in the presence of saliva, as compared with those infected with virus alone.
View Article and Find Full Text PDFBackground: Malaria control is heavily reliant on insecticides, especially pyrethroids. Resistance of mosquitoes to insecticides may threaten the effectiveness of insecticide-based vector control and lead to a resurgence of malaria in Africa.
Methods: In 21 villages in Southern Benin with high levels of insecticide resistance, the resistance status of local vectors was measured at the same time as the prevalence of malaria infection in resident children.
Background: Arboviral diseases are an important public health concerns. Vector control remains the sole strategy to fight against these diseases. Because of the important limits of methods currently used to assess human exposure to Aedes mosquito bites, much effort is being devoted to develop new indicators.
View Article and Find Full Text PDFBackground: Large-scale implementation of Indoor Residual Spraying and Insecticide Treated Nets has been implemented in Plateau Department, Benin between 2011 and 2014. The purpose of this study was to monitor the frequency and mechanisms of pyrethroid resistance in malaria vectors following the implementation of vector control tools for malaria prevention.
Methods: Anopheles larvae were collected in 13 villages twice a year from 2012 to 2014.
Background: The saliva of tsetse flies contains a cocktail of bioactive molecules inducing specific antibody responses in hosts exposed to bites. We have previously shown that an indirect-ELISA test using whole salivary extracts from Glossina morsitans submorsitans was able to discriminate between (i) cattle from tsetse infested and tsetse free areas and (ii) animals experimentally exposed to low or high numbers of tsetse flies. In the present study, our aim was to identify specific salivary synthetic peptides that could be used to develop simple immunoassays to measure cattle exposure to tsetse flies.
View Article and Find Full Text PDFBackground: The estimates of risk of malaria in early childhood are imprecise given the current entomologic and parasitological tools. Thus, the utility of anti-Anopheles salivary gSG6-P1 peptide antibody responses in measuring exposure to Anopheles bites during early infancy has been assessed.
Methods: Anti-gSG6-P1 IgG and IgM levels were evaluated in 133 infants (in Benin) at three (M3), six (M6), nine (M9) and 12 (M12) months of age.
Evaluation of vector control is crucial for improving malaria containment and, according to World Health Organization, new complementary indicators would be very valuable. In this study the IgG response to the Anopheles-specific cE5 salivary protein was tested as a tool to evaluate the efficacy of insecticide-treated nets in reducing human exposure to malaria vectors. Sera collected during a longitudinal study carried out in Angola, and including entomological and parasitological data, were used to assess the IgG response to the Anopheles gambiae cE5 in both children and adults, before and after the application of insecticide-treated nets.
View Article and Find Full Text PDFBackground: Malaria is the major parasitic disease worldwide caused by Plasmodium infection. The objective of integrated malaria control programs is to decrease malaria transmission, which needs specific tools to be accurately assessed. In areas where the transmission is low or has been substantially reduced, new complementary tools have to be developed to improve surveillance.
View Article and Find Full Text PDFBackground: Insecticide resistance in the mosquito vector is the one of the main obstacles against effective malaria control. In order to implement insecticide resistance management strategies, it is important to understand the genetic factors involved. In this context, we investigated the molecular basis of DDT resistance in the main malaria vector from Benin.
View Article and Find Full Text PDFInsensitive acetylcholinesterase resistance due to a mutation in the acetylcholinesterase (ace) encoding ace-1 gene confers cross-resistance to organophosphate and carbamate insecticides in Anopheles gambiae populations from Central and West Africa. This mutation is associated with a strong genetic cost revealed through alterations of some life history traits but little is known about the physiological and behavioural changes in insects bearing the ace-1(R) allele. Comparative analysis of the salivary gland contents between An.
View Article and Find Full Text PDFAedes borne viruses represent public health problems in southern countries and threat to emerge in the developed world. Their control is currently based on vector population control. Much effort is being devoted to develop new tools to control such arbovirus.
View Article and Find Full Text PDFObjective: Using human IgG antibody response to the Aedes Nterm-34 kDa salivary peptide as an indicator of human exposure to Aedes bites in surveying exposed populations from areas at risk of dengue virus (DENV) transmission in urban settings of Vientiane city, Lao PDR.
Methods: Enzyme-linked immunosorbent assay tests were performed to measure the IgG response to Nterm-34 kDa peptide in blood samples collected within a flavivirus seroprevalence survey carried out in 2006 including 3558 randomly selected individuals. The level of IgG response to the Nterm-34 kDa peptide in individuals was analysed in relation to the level of urbanisation of the individual's residence, areas that presented significant differences in the prevalence of recent DENV infection.
Background: The widespread use of insecticide-treated nets (LLINs) leads to the development of vector resistance to insecticide. This resistance can reduce the effectiveness of LLIN-based interventions and perhaps reverse progress in reducing malaria morbidity. To prevent such difficulty, it is important to know the real impact of resistance in the effectiveness of mosquito nets.
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