Background: Malaria in Cape Verde is unstable, with a sporadic and seasonal transmission of low endemicity. In this sense, the community perceptions regarding malaria transmission, their attitudes and practices against the disease are very important to understand and to better develop the best strategical policies to achieve malaria elimination goal. This study aim to assess the knowledge, attitudes and practices (KAP) of Cape Verdean population about malaria, a country in the elimination step of disease. Methods: A cross-sectional malaria KAP Survey was performed at the household level. A structured open questionnaire was developed and applied to residents of randomly selected households from 5 islands and 15 municipalities in Cape Verde. Correlation analyses were performed using a logistic regression model to determine the factors that are associated with the complete knowledge of the population about malaria. Results: A total of 1953 fully completed questionnaires were analysed, with majority of questionnaires administered in Santiago island (68.3%), mainly in the capital city of Praia, 38.43%. About 88% of the population knew the correct form of transmission, 96% had knowledge that the entire population is at risk of malaria and identified the main symptoms. Regarding the attitudes, 58% seek treatment atthe nearest health structure upon the apparition of the symptoms, 64% in the first 24 h and 88% within the first 48 h. More than 97% have heard about mosquito nets but only 19% used it. In practice, 53% use coils, 45% rely on household sprays and 43% have benefited from IRS. About 90% received information about malaria from media, mainly the TV and the radio (83 and 43%, respectively). In summary, 54% of the population has complete knowledge of the disease. Conclusion: The population of Cape Verde has a high level of knowledge about malaria, including its transmission, main symptoms and preventive and control measures. However, some gaps and misunderstandings have been noticed and contribute to the insufficient community involvement in actions against malaria. Therefore, is necessary to increase the knowledge of the population, leading to their full ownership and participation in community actions to contribute to the malaria elimination in the country.

Background

Background: Dirofilaria immitis, D. repens and Acanthocheilonema reconditum are the main causative agents of zoonotic canine filariosis. Methods: We developed a combined multiplex approach for filaria and Wolbachia detection using the 28S-based pan-filarial and 16S-based pan-Wolbachia qPCRs, respectively, involving a fast typing method of positive samples using triplex qPCR targeting A. reconditum, D. immitis and D. repens, and a duplex qPCR targeting Wolbachia of D. immitis and D. repens. The approach was complemented by a duplex qPCR for the differential diagnosis of heartworms (D. immitis and Angiostrongylus vasorum) and pan-filarial cox1 and pan-Wolbachia ftsZ PCRs to identify other filarial parasites and their Wolbachia, respectively. A total of 168 canine blood and sera samples were used to validate the approach. Spearmanʼs correlation was used to assess the association between filarial species and the strain of Wolbachia. Positive samples for both the heartworm antigen-test after heating sera and at least one DNA-positive for D. immitis and its Wolbachia were considered true positive for heartworm infection. Indeed, the presence of D. repens DNA or that of its Wolbachia as well as A. reconditum DNA indicates true positive infections. Results: The detection limit for Wolbachia and filariae qPCRs ranged from 5 × 10 −1 to 1.5 × 10 −4 mf/ml of blood. When tested on clinical samples, 29.2% (49/168) tested positive for filariae or Wolbachia DNA. Filarial species and Wolbachia genotypes were identified by the combined multiplex approach from all positive samples. Each species of Dirofilaria was significantly associated with a specific genotype of Wolbachia. Compared to the true positives, the approach showed excellent agreement (k = 0.98-1). Unlike D. immitis DNA, no A. vasorum DNA was detected by the duplex qPCR. The immunochromatographic test for heartworm antigen showed a substantial (k = 0.6) and a weak (k = 0.15) agreements before and after thermal pre-treatment of sera, respectively. Conclusions: The proposed approach is a reliable tool for the exploration and diagnosis of occult and non-occult canine filariosis. The current diagnosis of heartworm disease based on antigen detection should always be confirmed by qPCR essays. Sera heat pre-treatment is not effective and strongly discouraged.

BackgroundUntil very recently, Anopheles were considered naturally unable to host Wolbachia, an intracellular bacterium regarded as a potential biological control tool. Their detection in field populations of Anopheles gambiae sensu lato, suggests that they may also be present in many more anopheline species than previously thought.ResultsHere, is reported the first discovery of natural Wolbachia infections in Anopheles funestus populations from Senegal, the second main malaria vector in Africa. Molecular phylogeny analysis based on the 16S rRNA gene revealed at least two Wolbachia genotypes which were named wAnfu-A and wAnfu-B, according to their close relatedness to the A and B supergroups. Furthermore, both wAnfu genotypes displayed high proximity with wAnga sequences previously described from the An. gambiae complex, with only few nucleotide differences. However, the low prevalence of infection, together with the difficulties encountered for detection, whatever method used, highlights the need to develop an effective and sensitive Wolbachia screening method dedicated to anopheline.ConclusionsThe discovery of natural Wolbachia infection in An. funestus, another major malaria vector, may overcome the main limitation of using a Wolbachia-based approach to control malaria through population suppression and/or replacement.

People living in the tropical and subtropical regions of the world face an enormous health burden due to mosquito-borne diseases such as malaria, dengue fever, and filariasis. Historically and today, targeting mosquito vectors with, primarily, insecticide-based control strategies have been a key control strategy against major mosquito-borne diseases. However, the success to date of such approaches is under threat from multiple insecticide resistance mechanisms while vector control (VC) options are still limited. The situation therefore requires the development of innovative control measures against major mosquito-borne diseases. Transinfecting mosquitos with symbiotic bacteria that can compete with targeted pathogens or manipulate host biology to reduce their vectorial capacity are a promising and innovative biological control approach. In this review, we discuss the current state of knowledge about the association between mosquitoes and Wolbachia, emphasizing the limitations of different mosquito control strategies and the use of mosquitoes' commensal microbiota as innovative approaches to control mosquito-borne diseases.

BackgroundScaling-up of effective anti-malarial control strategies in Central-West region of Senegal has resulted in the sharp decline in malaria prevalence in this area. However, despite these strategies, residual malaria transmission has been observed in some villages (hot spots). The objective of this study was to assess the impact of indoor residual spraying (IRS) with pirimiphos-methyl on malaria transmission in hot spot areas.MethodsThe malaria vector population dynamics were monitored in each of the six selected villages (4 of which used IRS, 2 were unsprayed control areas) using overnight human landing catches (HLC) and pyrethrum spray catches (PSC). The host source of blood meals from freshly fed females collected using PSC was identified using the direct ELISA method. Females caught through HLC were tested by ELISA for the detection of Plasmodium falciparum circumsporozoite protein and Anopheles gambiae complex was identified using PCR.ResultsPreliminary data shown that the densities of Anopheles populations were significantly lower in the sprayed areas (179/702) compared to the control. Overall, malaria transmission risk was 14 times lower in the intervention zone (0.94) compared to the control zone (12.7). In the control areas, three Anopheles species belonging to the Gambiae complex (Anopheles arabiensis, Anopheles coluzzii and Anopheles melas) maintained the transmission, while only An. coluzzii was infective in the sprayed areas.ConclusionThe preliminary data from this pilot study showed that IRS with the CS formulation of pirimiphos-methyl is likely very effective in reducing malaria transmission risk. However, additional studies including further longitudinal entomological surveys as well as ecological and ethological and genetical characterization of vectors species and their populations are needed to better characterize the entomological impact of indoor residual spraying with pirimiphos-methyl in the residual transmission areas of Senegal.

BackgroundMalaria, despite being preventable and treatable, continues to be a major public health problem worldwide. The archipelago nation of Cape Verde is in a malaria pre-elimination phase with the highest potential to achieve the target goal of elimination in 2020.MethodsNationwide malaria epidemiological data were obtained from the Cape Verde health information system that includes the individual malaria case notification system from all of the country’s health structures. Each case is reported to the surveillance service then to the National Malaria Control Programme, which allowed for compilation in the national malaria case database. The database was analysed to assess the origin of the malaria cases, and incidence was calculated from 2010 to 2016 by sex and age. The health centre, health district and month of diagnosis were evaluated, as well as the sex and the age of the patients, allowing a direct descriptive analysis of national data to provide an up-to-date malaria epidemiological profile of the country. Malaria cases were classified as imported or indigenous, and then, geographical analyses were performed using a unique Geographical National Code with Quantum Geographic Information System 2.16.2 software to map the cases by municipalities. The overall temporal evolution of cases was analysed to assess their monthly and yearly variations from 2010 to 2016.ResultsMalaria is unstable in Cape Verde, with inter-annual variation and the majority of infections occurring in adult males (> 20 years). The indigenous cases are restricted to Santiago (96%) and Boavista (4%), while imported cases were recorded in all the nine inhabited islands, originating from neighbouring countries with ongoing malaria transmission; from Lusophone countries (25% from Angola, 25% from Guinea-Bissau), followed by the Republic of Senegal (12%) and Equatorial Guinea (10%). In 2010–2012, more imported (93 cases) than indigenous cases (26 cases) were observed; conversely, in 2013 and 2014, more indigenous cases (49) than imported cases (42) were reported. In 2015 there were 20 imported cases and only 7 indigenous cases. Finally, in 2016, there were 47 indigenous cases and 28 imported cases. The mapping of cases by municipality and country of origin was possible with GIS analyses.ConclusionWhile Cape Verde remains on track to achieve malaria elimination by 2020 owing to the reduction of the annual incidence to below 0.1%, the country still records cases of indigenous and imported malaria. However, the indigenous cases are exclusively confined to the Santiago and Boavista islands, while the imported cases recorded nationwide originate only from the African continent, mainly from adult men from the Lusophone countries. Cape Verde needs to target interventions to remove residual foci on Santiago and Boavista islands to reduce malaria lethality to zero and prevent its reintroduction from African countries via transmission across the archipelago. Cape Verde is a good example of local authority’s commitment to tackle malaria and work towar...

Biological control against malaria and its transmission is currently a considerable challenge. plantassociated bacteria of the genus Asaia are frequently found in nectarivorous arthropods, they thought to have a natural indirect action on the development of plasmodium in mosquitoes. However, virtually nothing is known about its natural cycle. Here, we show the role of nectar-producing plants in the hosting and dissemination of Asaia. We isolated Asaia strains from wild mosquitoes and flowers in Senegal and demonstrated the transmission of the bacteria from infected mosquitoes to sterile flowers and then to 26.6% of noninfected mosquitoes through nectar feeding. Thus, nectar-producing plants may naturally acquire Asaia and then colonize Anopheles mosquitoes through food-borne contamination. finally, Asaia may play an indirect role in the reduction in the vectorial capacity of Anopheles mosquitoes in a natural environment (due to Plasmodium-antagonistic capacities of Asaia) and be used in the development of tools for Asaia-based paratransgenetic malaria control.Nectarivory is extremely common in insects. Nectar is a sugar-rich liquid specially produced by plant glands (nectaries) to attract pollinating animals. The majority of nectarivorous insect species belong to the families Diptera, Coleoptera, Lepidoptera, Hymenoptera and Hemiptera. Nectar consumption has been established for many lower dipteran taxa, including not only the Tipulidae (crane flies), Cecidomyiidae (gall midges), Sciaridae (root gnats) and Mycetophilidae but also blood-feeding species, such as Ceratopogonidae (biting midges) and Culicidae (mosquitoes) 4 . The Diptera possess an elongated tube, which has characteristic morphological and functional adaptations to feed on either floral nectar (e.g., Bombyliidae, Syrphidae, and Nemestrinidae), vertebrate blood (e.g., Tabanidae and Glossinidae) or both (Culicidae, Simuliidae, and Ceratopogonidae) 5 .Male and female mosquitoes require sugar to obtain the energy they need to survive in their natural environment. Their sugar requirements are generally fulfilled from flower nectar near larval breeding sites or around adult resting sites. Plant nectar is a nutritional supplement that females often use between blood meals and when hosts are absent or rare. It is also used as an energy source and thus allows both male and female mosquitoes to survive in their environment 6 . Thus, plants play a very important role in mosquito survival in their natural environment, providing them with an easily accessible meal, which increases their life span and reduces contact with humans 6 . Plants also provide male mosquitoes with enough energy to successfully fertilize females, thus ensuring species perennity 7 . Mosquitoes are attracted by the odors emitted by plants and use those odors to locate plants that can provide the sugar and/or chemicals they need to survive in their natural environment 6 .Several studies have discussed the importance of arthropod vector microbiota for the prevention of certain vector-borne dis...