- UB
Introduction: Malaria remains a major public health problem in Cameroon. In the frame of a larviciding trial, a study was conducted to assess the efficacy of VectoMax®G for the control of mosquito densities and, malaria transmission in the city of Yaoundé.
Methods: Clusters were grouped into treated sites, which received larviciding with VectoMax®G (Bacillus thuringiensis and Bacillus sphaericus); and into control sites. Adult mosquitoes were collected in both control and treated sites using Centers for disease control and prevention light traps (CDC-LTs) and human landing catches (HLC) in July, September, and November 2019 and in eight districts of Yaoundé. Mosquitoes were sorted by genus and identified to the species level using polymerase chain reaction. The enzyme-linked immunosorbent assay method was used to determine mosquito infection to Plasmodium.
Results: Amongst the 915 mosquitoes collected, Culex species were predominant (66.34%). The proportion of mosquitoes collected in control sites was high compared to treated sites. The difference was significant in Anophelinae (χ2= 98.69; P<0.0001) with a reduced rate of 85.52% in An. gambiae s.l. Out of 122 An. gambiae s.l. analysed, 77.05% were An. coluzzii and 22.95% An. gambiae sensu stricto. The infection rate of An. gambiae s.l. by Plasmodium falciparum was 1.9% in control sites (5/260) and none in treated sites and therefore, a risk of malaria transmission in control sites.
Conclusion: Our findings suggest that larviciding with VectoMax®G can be highly effective for reducing mosquito densities and malaria transmission in the city of Yaoundé Cameroon.
Impact of study: This work could serve as a suggestion to the ministry of public health on a suitable method of mosquito vector control to manage the situation of insecticide resistance.
Keywords: Larviciding, Vectomax G, Malaria, Yaoundé
