Effect of atmospheric temperature and rainfall on malaria incidence rates in selected districts of the three ecological zones of Zambia, over a seven- year period : retrospective study.
Date
2023
Authors
Silombe, Mwenya
Journal Title
Journal ISSN
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Publisher
The University of Zambia
Abstract
In 2020, it was estimated that 241 million malaria cases were recorded globally, increasing from 227 million in 2019, with African countries contributing most to the increase. Studies have indicated that malaria is influenced by climate. Climate factors such as temperature and rainfall affect malaria incidences through changes in the mosquito life cycle and duration or parasite behavior such as fertilization and breeding of mosquito’s eggs. This study was conducted to determine the influence of atmospheric temperature and rainfall on confirmed malaria incidences in six selected districts of the three ecological zone of Zambia between the period of 2014 to 2020. Retrospective analytical comparative study design was used in this
research. The first stage involved identifying the three ecological zones in Zambia; followed by randomly selecting two districts from each ecological zone. A total of six districts were selected and considered in the study. The second stage involved the collection of quantitative (secondary) data from the Ministry of Health and Meteorological Department both at district level. Confirmed malaria cases from 2014 to 2020 were used in this study. Microsoft® excel ® 2020 version was used to create graphs to show the annual trends of rainfall, atmospheric temperature and confirmed malaria incidences in six selected districts of the three ecological zones. Pearson’s correlation analysis was used to measure the relationship between annual
atmospheric temperature, rainfall (independent variables) and confirmed malaria incidences (dependent variable). The results showed a low positive Pearson correlation of statistical significance between annual rainfall and confirmed malaria incidences in the three ecological zones of Zambia from 2014 to 2020 (r= 0.476, p < 0.001). This entails that; annual confirmed malaria incidences and rainfall had a direct relationship. The Pearson correlation between annual atmospheric temperature and confirmed malaria was low negative relationship but statistically significant (r= -0.451, p< 0.003). This entails that; an increase in the independent variable (temperature) leads to a decrease in the dependent variable (malaria incidences).
Districts of the ecological zone 3 received the highest amount of rainfall and also recorded the highest number of confirmed malaria incidences. The districts of the ecological zone 1 recorded the highest annual atmospheric temperature but lowest numbers of confirmed malaria incidences. This study conclusively reports that there was a direct relationship between annual rainfall and confirmed malaria in the three ecological zones. Further, there was an inverse relationship (low negative correlation) between annual atmospheric temperature and confirmed malaria incidences but this relationship was statistically significant. Future studies should consider increasing number of sampling districts from each ecological zone.
Description
Thesis of Master of Science in Ecological Public Health.