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Yoshimizu, M.

Publications and source records attributed to Yoshimizu, M..

3 recordsLinked to original sources

Anopheles azevedoi (Ribeiro, 1969) in Angola: New geographical records, molecular characterization, and insecticide susceptibility profile of a commonly misidentified species

BACKGROUNDAngola ranks among the five countries with the highest malaria burden globally. The Ministry of Health in Angola has consistently partnered with international donors to sustain entomological surveillance and vector control strategies in a context of high malaria burden. METHODSVector surveillance was carried out in Luanda, Benguela, Namibe and Cuanza Sul provinces from 2016-2022. Collected adult mosquitoes were tested to assess the presence of Plasmodium parasites and determine blood sources. Larvae collections provided live material to test insecticide susceptibility in local Anopheles populations. Taxonomic determination of mosquitoes was based on external morphology and confirmed with molecular assays. The presence of Anopheles azevedoi was confirmed through morphology and genetic sequences, and errors in the original species determination were detected, discussed and corrected. OBJECTIVESThe study aimed to update the geographical range of Anopheles azevedoi in Angola and monitor the species susceptibility to public health insecticides. FINDINGS and MAIN CONCLUSIONSWe report on populations of Anopheles azevedoi occurring along the western coast of Angola, a highly abundant species with anthropophilic behavior in urban areas. Anopheles azevedoi is widely resistant to pyrethroids and DDT but fully susceptible to chlorfenapyr. We contribute with COI and ITS-2 barcoding sequences for future species identification and explain the reasons for which this species has been for long misidentified in Angola.

zoology↗

Anopheles stephensi larval habitat superproductivity and its relevance for larval source management in Africa

The invasion of Africa by Anopheles stephensi poses a significant threat to malaria elimination. As An. stephensi exploits a wide array of urban artificial larval habitats, it may be less impacted by rainfall variability compared to other native Anopheles species. We empirically investigated this assumption by quantifying the seasonal transition of an established population from eastern Ethiopia between rainy and dry periods. Monthly larval surveys generated evidence of significant heterogeneity between seasons in the type of habitat and their productivity. As the dry season progressed, An. stephensi productivity significantly concentrated in large water reservoirs (for drinking and construction) to a point in which up to 77% of all larvae originated from 23% of the sites. Such superproductive sites were primarily water cisterns used for residential or construction purposes. A two-patch metapopulation model of An. stephensi linked to rainfall data recreated the seasonal larval dynamics observed in the field and predicted that larval control targeted on superproducer water reservoirs, when implemented at coverages higher than 60%, may lead to An. stephensi elimination. Our findings highlight the role of environmental variability in regulating An. stephensi populations and open the window for the deployment of control strategies that exploit major mosquito population bottlenecks.

ecology↗

Community-Based Entomological Surveillance and Control of Vector-Borne Diseases: A Scoping Review

Community-based surveillance and control methods (CBMs) present opportunities to decentralize surveillance and control efforts while simultaneously enhancing community education, leadership, and participation in the fight against vector-borne diseases (VBDs). A scoping review was conducted to describe how CBMs are being utilized currently to combat malaria, dengue fever, Chagas disease, tick-borne diseases (TBDs) and other mosquito-borne diseases (MBD) exclusive of dengue and malaria, and to overall highlight key approaches, lessons learned, potential challenges, and recommendations. A total of 304 potential publications were identified among which 82 met the inclusion criteria. This scoping review highlighted the following benefits to CBMs: cost savings, increased sustainability, increased community knowledge, human behavior changes, increased surveillance coverage, ease in deployment, and the creation of larger, more diverse entomological datasets. Potential challenges highlighted include: participant retention and motivation, participant recruitment and incentives, continued governmental support, data quality, and collaboration with local municipal authorities. CBMs are commonly and successfully used in vector surveillance and control systems, but the chosen vector management method varies by vector-borne disease and region of the world. Additional research is needed to support the implementation of CBMs including cost-effectiveness studies and those studies with negative outcomes. Taken together, this scoping review highlights key aspects, potential challenges, and benefits of CBMs, and outlines potential future directions for incorporating CBMs into VBD control and elimination programming, and potential for community based integrated vector management (IVM) approaches.

scientific communication and education↗