Insecticide susceptibility of natural populations of Anopheles coluzzii and Anopheles gambiae (sensu stricto) from Okyereko irrigation site, Ghana, West Africa

Abstract

BackgroundThe increasing spread of insecticide resistance in malaria vectors has been well documented across sub-Saharan Africa countries. The influence of irrigation on increasing vector resistance is poorly understood, and is critical to successful and ethical implementation of food security policies. This study investigated the insecticide resistance status of An. gambiae (s.l.) mosquitoes collected from the irrigated rice area of Okyereko, a village containing about 42 hectares of irrigated field within an irrigation project plan in the Central Region of Ghana. Large amounts of insecticides, herbicides and fertilizers are commonly used in the area to boost the annual production of the rice.MethodsMosquito larvae were collected and adults were assayed from the F1 progeny. The resistance status, allele and genotype were characterized using WHO susceptibility testing and PCR methods respectively.ResultsThe An. gambiae (s.l.) populations from Okyereko are highly resistant to DDT and pyrethroid insecticides, with possible involvement of metabolic mechanisms including the elevation of P450 and GST enzyme as well as P-gp activity. The population was mostly composed of An. coluzzii specimens (more than 96 %) with kdr and ace-1 frequencies of 0.9 and 0.2 %, respectively.ConclusionThis study brings additional information on insecticide resistance and the characterization of An. gambiae (s.l.) mosquitoes from Okyereko, which can be helpful in decision making for vector control programmes in the region.

Evaluation of piperonyl butoxide in enhancing the efficacy of pyrethroid insecticides against resistant Anopheles gambiae s.l. in Ghana

“…Pyrethroid resistance has in recent years become widespread among anopheline mosquitoes in Western, Eastern, Central and South Africa [ 5 , 6 , 8 , 20 – 32 ]. In spite of that, most of the malaria vector control programme of countries is still relying on pyrethroid treated tools to control the vectors [ 1 , 33 – 37 ].…”

Impact of Urban Agriculture on the Species Distribution and Insecticide Resistance Profile of <i>Anopheles gambiae s.s.</i> and <i>Anopheles coluzzii</i> in Accra Metropolis, Ghana

“…Anopheles gambiae s.s. and Anopheles coluzzii constitute the main malaria vectors in Ghana and particularly in the Southern part of the country where Accra is located. Anopheles gambiae s.s., (formerly named A. gambiae s.s. molecular form) prefers rain-dependent pools, sunny and temporally puddles while A. coluzzii (formerly A. gambiae s.s. M molecular form) exploits preferentially immature sites that exist across seasons and also linked to human activities such as rice cultivation, urbanization and irrigation [13].…”

Investigation of the Role of ABC Transporters in Pyrethroids Resistance in the Major Malaria Vector Anopheles coluzzii from Northern Nigeria

“…This indicates that ABC transporter may not be involved in the pyrethroid resistance in populations from Hadiyau, Auyo Northern Nigeria. In contrast, Joseph et al 2016 [12] reported in An. gambiae s. l. collected from rice irrigation fields of Okyereko in Ghana, that An.…”