Malaria among schoolchildren in urban, peri-urban and rural settings in Eastern Ethiopia: repeated cross section study

Despite malaria control efforts, schoolchildren continue to exhibit high malaria prevalence. While multiple studies report varying malaria prevalence among schoolchildren across Africa, there is an evidence gap in comparing malaria prevalence across urban, peri-urban and rural settings, particularly in the context of changing transmission dynamics due to Anopheles stephensi spread in Africa. Hence, this study aimed to assess epidemiology of malaria among schoolchildren in different eco-epidemiological settings during high and low transmission seasons in Eastern Ethiopia.

A repeated cross-sectional study was conducted in November 2023 and May 2024 among selected primary schoolchildren in Eastern Ethiopia. Sample size was calculated using a single population proportion formula and design effect was considered. Simple random sampling technique was employed to select schools and students. Finger prick blood was collected, thin and thick blood smears were prepared, stained with 10% Giemsa and examined microscopically. Data on sociodemographic characteristics, and other determinant factors were collected using a pretested structured questionnaire. Data were collected using Open Data Kit (ODK) software and analyzed using Stata software. Binary logistic regression analysis was conducted to assess associations between independent variables and malaria infection.

The prevalence of malaria among schoolchildren during high and low transmission season was 5.1% (95% CI 3.84, 6.7) and 2.24% (95% CI 1.48, 3.37) respectively. With regard to the ecological settings, the prevalence of asymptomatic malaria among schoolchildren during high transmission in urban, peri-urban and rural were 7.3%, 4.97%, 2.9% (P = 0.007), respectively. Similarly, the prevalence during low transmission season in urban, peri-urban and rural were 3.5%, 1.2%, and 2.04% (p = 0.3) respectively. Plasmodium falciparum was the dominant species in all school settings, both during high (83%) and low transmission (59%) seasons. Non-use of ITN (AOR 2.2; 95% CI 1.2, 3.99) and presence of under-five children (AOR 1.9; 95% CI 1.1, 3.38) in the household were identified as predictors of malaria infection during the high transmission season. Similarly, the marital status of the child's household head (AOR 4.4; 95% CI 1.4-13.8) was associated with malaria infection during the low malaria transmission season.

Malaria intervention efforts should target all school settings, with particular emphasis on urban and peri-urban areas. There is a need to strength the use of insecticide-treated nets, focusing on households with under-five children, and malaria interventions should consider household socio-demographic contexts to reduce the malaria burden effectively.