Associations Between Drought and Childhood Diarrhea in Low- and Middle-Income Countries

Abstract

BACKGROUND AND AIM: Diarrheal diseases are the fifth leading cause of death among children under five. Climate change is projected to intensify hydrological variability and extreme weather events such as drought. However, current evidence on the association between drought and diarrhea is scarce. We aim to quantify this association in children under five in low- and middle-income countries (LMICs). METHODS: Data on childhood diarrhea for 38 LMICs during 2010-2018 were obtained from the Demographic and Health Surveys program. The 24-month scale Standard Precipitation Evapotranspiration Index (SPEI) with a 0.5 degrees spatial resolution across the survey sites was retrieved from the Global SPEI database. Drought was defined as severe drought (-1.6 SPEI ≤ -1.3), extreme drought (-2.0 SPEI ≤ -1.6), or exceptional drought (SPEI ≤ -2.0). Binomial generalized linear mixed models with random effects for survey cluster, and survey country and year, were constructed to examine the association of diarrhea with drought, adjusting for survey month and other sociodemographic and water, sanitation, and hygiene-related variables. RESULTS:In total there were 294,453 childhood (5 years) diarrhea occurrences recorded during the two weeks before the interview; the overall prevalence was 11.6%, with the highest prevalence among children aged 6-23 months. After controlling for inter-cluster heterogeneity and country-year variability, exposure to severe, extreme and exceptional drought events during the preceding two-year window was associated with an increased risk of diarrhea of 8% (95% confidence interval (CI) 2%-16%), 33% (95% CI 26%-42%), or 47% (95% CI 30%-67%), respectively, compared to non-exposure to drought. CONCLUSIONS:Our study indicates all levels of drought are significantly associated with elevated risks of childhood diarrhea in LMICs, with a higher risk associated with more severe drought. KEYWORDS: Children's environmental health, infectious diseases, climate, natural disasters