Jonathan Chome Ngala , Luna Kamau , Paul Mireji , Jane Mburu , Charles Mbogo

1. Department of Biomedical Sciences – Pwani University, P.O. Box 195-80108, Kilifi, Kenya
2 Centre for Biotechnology Research and Development, Kenya Medical Research Institute, P.O. Box 54840-00200, Nairobi, Kenya
3. Public Health Department, Kenya Medical Research Institute-Wellcome Trust-University of Oxford Programme, GPO, Nairobi, Kenya
4. Department of Biochemistry and Molecular Biology, Egerton University, P.O. Box 536, Egerton, Kenya
5. Department of Animal Sciences, Egerton University, P.O Box 536, Egerton, Kenya
6. Kenya Medical Research Institute-Wellcome trust Research Programme-P.O Box 230-80108, Kilifi, Kenya
Author    Correspondence author
Journal of Mosquito Research, 2015, Vol. 5, No. 14   doi: 10.5376/jmr.2015.05.0014
Received: 24 Jun., 2015    Accepted: 25 Jul., 2015    Published: 16 Sep., 2015

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Ngala C.J., Kamau L., Mireji Paul O., Mburu J. and Mbogo C., 2015, Prevalence of Malaria Amongst Children 0 - 4 Years in Olugbo, Odeda Local Government, Ogun State, Nigeria, Journal of Mosquito Research, Vol.5, No.14 1-8 (doi: 10.5376/jmr.2015.05.0014)

The ability of Anopheles mosquito to transmit malaria in nature is partly enhanced by; resistance of mosquito to insecticides, feeding preference for human host and infection by Plasmodium falciparum. An assessment was conducted to determine the status of these parameters in Anopheles populations in Mwea and Ahero rice irrigation schemes in Kenya. This was important in order to understand their potential influence on local malaria transmission. A total of 1,200 female Anopheles mosquitoes (gravid and blood fed) were sampled from both sites by indoor and outdoor methods. Anopheles samples identification to their respective species in the field was done using morphological features and taxonomic keys. In Mwea scheme, all the 600 Anopheles mosquitoes collected were An. gambiae s.l out of which 195 were gravid. In Ahero, 250 An. gambiae s.l (out of which 81 were gravid) and 350 An. funestus (out of which 181 were gravid) were collected. Gravid Anopheles mosquitoes were allowed to oviposit to give F₁ generations in the insectary. These F₁, (four replicates of 25 mosquitoes per species per insecticide) were assessed for susceptibility to permethrin, deltamethrin, dichlorodiphenyltrichloroethane (DDT), bendiocarb or fenitrothion using standard WHO protocol. Susceptible An. gambiae s.s Kisumu strain (25 mosquitoes per the 100 test mosquitoes) was used as positive control. The 1,200 field samples were further identified to their respective species using rDNA-PCR using their legs and wings. Source (s) of blood meal in 405 An. gambiae s.l from Mwea, 169 An. gambiae s.l and 269 An. funestus from Ahero were determined using blood meal Elisa. The presence of Plasmodium falciparum Welch, 1897 in the salivary glands was assessed by sporozoite Elisa in all the field collected samples. All Anopheles mosquito samples from Mwea were Anopheles arabiensis Patton, 1905, while those from Ahero were a mixed species of Anopheles arabiensis (41.7%), Anopheles funestus sensu stricto Giles, 1900 (57%), Anopheles rivulorum Leesoni, 1935 (0.66%), Anopheles leesoni Evans, 1931 (0.3%) and Anopheles parensis Gillies, 1935 (0.3%). Mosquito samples from both study sites showed reduced susceptibility to the test insecticides. An. arabiensis mosquitoes from Mwea had a human blood meal index at 0.22 (n=405).  P. falciparum circumsporozoite infection in An. arabiensis from Mwea were reported in Murinduko village at 1.5% (n=200). In Ahero, human blood meal indices were at 0.00 (n=169) and 0.17 (n=269) for An. arabiensis and An. funestus respectively. P. falciparum circumsporozoite infections in An. funestus sampled from Kamagaga and Wagai villages in Ahero were at 5% (n=147) and 2.2% (n=183) respectively.

Anopheles; Plasmodium falciparum; Insecticide resistance; Host preference