Diarrhoeal diseases in Soweto, South Africa, 2020: a community survey

Background: In South Africa, there are limited data on the burden of diarrhoea at a community level, specifically in older children and adults. This community survey estimated rates of and risk factors for diarrhoea across all ages and determined the proportion of cases presenting to healthcare facilities. Methods: Randomly sampled households were enrolled from an existing urban health and demographic surveillance site. A household representative was interviewed to determine risk factors and occurrence of diarrhoea in the household, for all household members, in the past two weeks (including symptoms and health seeking behaviour). Diarrhoeal rate of any severity was calculated for 15 years age groups. Risk factors for diarrhoea and factors associated with health seeking behaviour were investigated using binomial logistic regression. Results: Diarrhoeal rate among respondents (2.5 episodes/person-year (95%CI, 1.8-3.5)) was significantly higher than for other household members (1.0 episodes/person-year (95%CI, 0.8-1.4); IRR=2.4 (95%CI, 1.5-3.7) p<0.001). Diarrhoeal rate was not significantly different between age groups, however younger children (<5 years) were more likely to present to healthcare facilities (OR=5.86 (95%CI, 1.09-31.37), p=0.039). Having a child between 5-15 years in the household was associated with diarrhoea (OR=2.26 (95% CI, 1.32-3.86), p=0.003). While 26.4% of cases sought healthcare, only 4.6% of cases were hospitalised and only 3.4% of cases had a stool specimen collected. Conclusion: Diarrhoeal rate was high across all age groups in this community; however, older children and adults were less likely to present to healthcare, and are therefore underrepresented through facility-based clinical surveillance.