Insecticide resistance in malaria vectors in Kumasi, Ghana
No Thumbnail Available
Date
2016
Journal Title
Journal ISSN
Volume Title
Publisher
BioMed Central
Abstract
Background: There have been recent reports of surge in resistance to insecticides in pocketed areas in Ghana
necessitating the need for information about local vector populations and their resistance to the insecticides approved by
the World Health Organization (WHO). We therefore studied a population of malaria vectors from Kumasi in the Ashanti
Region of Ghana and their resistance to currently used insecticides. We conducted susceptibility tests to the four major
classes of insecticides by collecting larvae of anopheline mosquitoes from several communities in the region. Surviving
adults from these larvae were then subjected to the WHO-approved susceptibility tests and characterization of
knockdown resistance and acetylcholinesterase mutant genes.
Results: Out of 619 Anopheles specimens sampled, 537 (87%) were identified as Anopheles gambiae (sensu stricto),
which was also the species with the lowest knockdown resistance mutant gene, 61% (P = 0.017). Knockdown resistance
mutant gene was as high as 91% in An. coluzzii. Mosquitoes collected showed susceptibility ranging from 98–100% to
organophosphates, 38–56% to carbamates and 15–47% and 38–46% to pyrethroids and organochlorides, respectively.
The knockdown resistance mutation frequency of Anopheles gambiae (sensu lato) mosquitoes that were exposed to
both pyrethroids and organochlorides was 404 (65%). Acetylcholinesterase mutant gene was not found in this
population of vectors.
Conclusion: Our study shows that pyrethroids have the highest level of resistance in the population of mosquito vectors
studied probably due to their frequent use, especially in impregnation of insecticide-treated nets and in insecticides used
to control pests on irrigated vegetable farms. We recommend studies to monitor trends in the use of all insecticides and
of pyrethroids in particular.
Description
This article is published by BioMed Central.
Keywords
Citation
Baffour-Awuah et al. Parasites & Vectors (2016) 9:633 DOI 10.1186/s13071-016-1923-5