Background Diarrhoeal diseases cause a heavy burden in developing countries. Although studies have described the seasonality of diarrhoeal diseases, the association of weather variables with diarrhoeal diseases has not been well characterized in resource-limited settings where the burden remains high. We examined short-term associations between weather and hospital visits due to diarrhoea among children in seven low- and middle-income countries. Methodology Hospital visits due to diarrhoeal diseases in under 5 years old were collected from seven sites in The Gambia, Mali, Mozambique, Kenya, India, Bangladesh, and Pakistan via the Global Enteric Multicenter Study, from December 2007 to March 2011. Daily weather data during the same period were downloaded from the –ERA5-Land. We fitted time-series regression models to examine the relationships of daily diarrhoea cases with daily ambient temperature and precipitation. To account for between-site variability, we used a multivariate random-effects meta-regression model. Principal findings The relative risk (RR) of diarrhoea with temperature exposure ranged from 0.24 to 8.07, with Mozambique and Bangladesh showing positive associations, while Mali and Pakistan showing negative associations. The RR for precipitation ranged from 0.77 to 1.55, with Mali and India showing positive associations, while the only negative association was observed in Pakistan. Meta-analysis showed substantial heterogeneity in the association’s temperature–diarrhoea and precipitation–diarrhoea across sites, with I2 of 84.2% and 67.5%, respectively. Conclusions Child diarrhea and weather factors have diverse and complex associations across South Asia and Sub-Saharan Africa, influenced by pathogens, treatment, and nutrition. Diarrhoeal surveillance system settings should be conceptualized based on the observed pattern of climate change in these locations.

The authors have declared no competing interest.

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We have taken ethical approval from School of Tropical Medicine and Global Health (TMGH), Nagasaki University.

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