Association of Meteorological Factors with Two Principal Malaria Vector Complexes in the University of Agriculture Makurdi Community, Central Nigeria

Abstract

Association between meteorological indices and two major malaria vectors - Anopheles gambiae and Anopheles funestus complexes was determined in the Federal University of Agriculture Makurdi community, Nigeria, from July, 2015 to June, 2016. Meteorological data (Temperature, Rainfall and Relative Humidity) were obtained at the Nigerian Meteorological Agency, Tactical Air Command in Makurdi. Adult Anopheles mosquitoes (n = 3,053), comprising Anopheles gambiae s.l. [1,981(64.9%)] and Anopheles funestus complex [1,072(35.1%)], were collected indoors across four localities in the University Community and identified using standard keys and procedures. There were no marked fluctuations in mean atmospheric temperature throughout the study period, with the highest records of 35.9°C and 37.9°C for February and April, 2016 respectively. Relative humidity increased proportionally to rainfall, ranging from 46% - 89%. The Anopheles vector population was significantly (P < 0.05) higher during the wet season than the dry season. Pearsons’s correlation showed strong negative and significant relationship (r = -0.707, -0.653, P < 0.05) between temperature and the Anopheles species across the localities. Rainfall and relative humidity correlated positively and significantly (r = 0.735, 0.632, P < 0.05) with the Anopheles species’ population. Regression analysis showed strong linear relationships (R2 = 0.506465, R2 = 0.526724 and R2 = 0.665319 for temperature, rainfall and humidity respectively) between meteorological indices and the Anopheles population. This work has added to the existing data on the relationship between malaria vectors and weather factors which may enhance knowledge on malaria entomology and future malaria control interventions in the study area and beyond.