Determination of sporozoite infection rate of indoor resting female Anopheles mosquitoes in Gombe South, Gombe State, Nigeria

Abstract

Infected female Anopheles mosquitoes are the culprits of malaria. The abundance and distribution of malaria vectors in communities contribute significantly in malaria transmission. Understanding the magnitude and intensity of sporozoite infection rates is very sensitive and powerful indices for describing the epidemiology of malaria which will aid in strategizing malaria control programme. The present study determines the sporozoite infection rates of female Anopheles mosquitoes in the four Local Government Areas (LGA) of Gombe South, Gombe State, Northeastern Nigeria. Mosquitoes were collected using Pyrethrum Spray Catch (PSC) and were dissected to check the presence of sporozoites. Out of the 1,860 female Anopheles mosquitoes dissected, 665(35.8%) were infected with sporozoites. The highest infection rate was observed from Kaltungo LGA 145(41.7%), followed by Billiri LGA 182(36.3%), and 205(35.4%) was recorded from Balanaga. The lowest infectivity rate was observed from Shongom LGA 133(30.9%), p<0.005 which is highly significant statistically. With regards to monthly distribution of sporozoites, the highest infection rate was recorded in December (64.7%), January 60.0%, (64.5%), and August (60.7%) from Balanga, Billiri, Kaltungo and Shongom LGA respectively. Meanwhile the least was observed in July (2.8%), December (7.7%), April (20.0%), and March (11.6%) from Balanga, Billiri, Kaltungo and Shongom LGA respectively, p<0.005 which is highly significant statistically. However, (0.0%) sporozoite infection was obtained in September and March from Billiri, Kaltungo and Shongom LGA respectively. The present study therefore recommends malaria vector control through community based efforts by destruction of mosquitoes breeding sites, use of insect’s repellents, environmental sanitation and application of oil in stagnant water in order to reduce vectors population.