Larval density and physicochemical properties of three different breeding habitats of Anopheles mosquitoes in Sudan Savannah Region of Jigawa State, Nigeria

Abstract

Mosquitoes are tiny insects that can serve as vectors for numerous infectious diseases like malaria. Malaria is considered as one of the major causes of mortality, loss of productivity and a major contributor of poverty in the African continent. In 2020, most global malaria cases (94%) were recorded in the Africa Region. In Nigeria, about 97% of the estimated populations are at risk of malaria, with up to 27% and 24% of Africa and global malaria deaths respectively in 2018. Malaria control programmes in Africa have challenge of rising insecticide resistance in the main anopheline vectors, this affects primary malaria vector control interventions. In Africa, the dominant mosquito species that transmit malaria parasites are mainly Anopheles gambiae s.s. A key control strategy against major mosquito- borne diseases involves targeting mosquito vectors to disrupt the transmission of diseases. Environmental changes can alter the genetic structure, protein profiles and enzymes of mosquitoes leading to increase in insecticide resistance. Knowing the ecology, spatial distribution of mosquito larvae, and some environmental features like physicochemical factors are important in tackling insecticide resistance. Water and larval samples were collected from three Anopheles mosquito breeding sites in August, September and October, 2019. Physicochemical parameters, larval densities and morphological specie identifications were determined. Results from this study reveal variation in levels of each studied parameter according to the site of the study. These variations can be attributed to differences in activities that occur in each site of the study.. Correlation studies indicated a significantly higher larval density in agricultural site relative to industrial and residential sites, this was by a magnitude of 10.65 and 41.30 respectively. Anopheles gambiae s.s. complex was found to be predominant in all the three study sites. These physicochemical parameters can either have negative or positive effect on mosquito biology depending on their levels, hence can affect vector control measures making it significant in terms of vector control programmes.