Malaria is a public health concern in Zimbabwe and its transmission varies geographically and seasonally, corresponding with the country's rainfall pattern. Information on density and distribution of malaria vectors, species composition, breeding sites and quality assurance of the spray programme is limited for Chiredzi District. This study investigated mosquito species composition and distribution during winter, blood meal sources of adult collections, characteristics of aquatic larval habitats and quality of spraying as well as the insecticide residual activity on sprayed walls. Anopheline larvae were collected from breeding habitats that were subsequently characterised. Adult anophelines were sampled from both inside human dwellings and outdoors. Mosquitoes collected were identified morphologically and further processed to sibling species by polymerase chain reaction (PCR) where necessary. The enzyme-linked immunosorbent assay was used to detect Plasmodium falciparum circumsporozoite proteins and multiplex PCR was used to detect blood meal source. WHO cone bioassays were conducted to monitor spray quality and insecticide residual activity on spayed walls. A total of 21 aquatic habitats were identified from which anopheline larvae were sampled. Of these, 9 (42.9 %) were classified as permanent, 7 (33.3 %) as seasonal and 5 (23.8 %) as temporal. Anopheles mosquitoes from both adult and larval collections totalled to 153, with the former collection method accounting for 69.9 % (107) and the latter for 31.1 % (46). The collected mosquitoes were identified as An. quadriannulatus and An. funestus respectively. Out of the blood-fed An. funestus females, 70 % (n = 10) had fed on human blood. None of the adult collected mosquitoes tested positive for P. falciparum circumsporozoite proteins. The aquatic habitats surveyed indicated that breeding sites were mainly man-made. Anopheles funestus was the only malaria vector recorded during this study. This species is a particularly efficient vector and its detection is a cause for concern. Furthermore, 70 % of the adult-collected An. funestus female specimens had fed on humans confirming this species' strong tendency toward anthropophagy. A more comprehensive and year-round investigation is essential to gather appropriate and relevant entomological indices on malaria transmission in Chiredzi so as to enable effective vector control.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 28 • No. 1