Effects of Climatic Factors on Malaria Prevalence in Calabar Metropolis, Cross River State, Nigeria

Abstract

Climate variability is widely considered a major driver of inter-annual variability of malaria.
However, detailed studies of the interaction of climatic parameters in influencing malaria in
high-risk areas have not been adequately researched. This study examined the effects of
climatic parameters on malaria prevalence in Cross River State, Nigeria. Reported cases of
malaria and climatic data were collected from the record unit of the General Hospital and
Nigerian Meteorological Agency, Calabar, Cross River State, Nigeria respectively for twentynine years (1983-2012).The study used both descriptive and inferential statistics to analyze the collected data. The descriptive statistics used include line and bar graphs, mean, mode, percentage and tables whereas, the inferential statistic mainly Pearson’s correlation, Multiple Regression Analysis (MRA), and Principal Component Analysis (PCA) were used to identify prominent factors that influence malaria prevalence in the area. The results obtained from the correlation analysis showed that malaria prevalence had a low positive and insignificant associations with maximum temperature (r = 0.331, p>0.05), minimum temperature (r = 0.313, p>0.05), wind speed (r = 0.119, p>0.05), sunshine (r = 0.355, p>0.05) and evapotranspiration (r = 0.357, p>0.05) on the one hand, and on the other, prevalence showed low negative and insignificant relationship with rainfall amount (r = -0.216, p>0.05) and relativity humidity (r = -0.285, p>0.05). The result revealed generally a low association
between malaria prevalence and climatic variables. The PCA identified maximum temperature to be responsible for malaria incidence in the wet season, while in the dry season, malaria prevalence is jointly influenced by rainfall amount and wind speed. The results showed that climatic variables have direct influence on malaria prevalence. Appropriate malaria prevention measures are required to reduce the prevalence of the disease in the area.