Insecticide resistance through molecular assays in Anopheles albimanus in the Northern Caribbean Coast of Nicaragua

Abstract

Malaria is a tropical disease caused by parasites of the genus Plasmodium spp. and is transmitted by mosquitoes of the genus Anopheles spp. and is a worldwide public health problem (WHO, 2022). In Nicaragua, most cases occur in the Caribbean Coast and despite the efforts made by the Ministry of Health, its frequency has increased in recent years. This is due to several factors, including the presence of insecticide resistance genes in mosquitoes associated with the historical use of pyrethroids in control interventions. Therefore, the present study had the purpose of evaluating insecticide resistance through the development of molecular assays in Anopheles albimanus in the Alemán neighborhood of the municipality of Puerto Cabezas, Northern Caribbean Coast Autonomous Region in the second semester of 2022. It is a quantitative, analytical, cross-sectional study, the sample consisted of female Anopheles albimanus mosquitoes collected in the Alemán neighborhood. Biological tests, enzyme activity tests and molecular tests were used to determine susceptibility and mechanisms of resistance to insecticides. Resistance to etofenprox was reported with a 53% mortality rate and to deltamethrin with a 29% mortality rate. The Anopheles albimanus presented a metabolic mechanism partially involved for Etofenprox and totally involved for Deltamethrin. It was found that 79% possess the kdr mutation which confers resistance to pyrethroid insecticides. In Nicaragua, resistance to insecticides associated with the kdr mutation is reported. It is necessary to continue surveillance and monitoring of insecticide resistance through the systematic application of biological, molecular and enzymatic tests for the creation of an insecticide rotation program.