Factors associated with acute diarrhea among children under five years of age in Sana’a City, Yemen: a facility-based frequency-matched case–control study

Diarrhea remains a major public health problem and a leading cause of morbidity and mortality among children under five years of age in low- and middle-income countries. This study aimed to examine the factors associated with acute diarrhea among children under five years of age in Sana’a City, Yemen. A facility-based frequency-matched case–control study was conducted from January to May 2025 in six public health facilities in Sana’a City. A total of 430 children under five years of age were enrolled, comprising 215 cases with acute diarrhea and 215 controls without acute diarrhea during the preceding three months. Data were collected through face-to-face interviews with mothers or caregivers using a structured questionnaire. Factors associated with acute diarrhea were assessed using univariable and unconditional multivariable logistic regression. Associations were reported as crude odds ratios (CORs) and adjusted odds ratios (AORs) with 95% confidence intervals (CIs). Statistical significance was set at p < 0.05. Several factors were independently associated with acute diarrhea. These included use of private treated drinking water (AOR = 15.51, 95% CI: 5.47–44.01), no household treatment of drinking water (AOR = 18.56, 95% CI: 1.36–54.37), the presence of open waste dumps or sewage near the household (AOR = 5.18, 95% CI: 2.68–10.02), and use of unimproved sanitation facilities (AOR = 4.04, 95% CI: 1.69–9.60). Other associated factors were insufficient monthly income (AOR = 2.04, 95% CI: 1.11–3.77), failure to wash hands with soap after changing diapers or assisting with defecation (AOR = 3.04, 95% CI:1.63–5.68), introduction of complementary foods before six months of age (AOR = 2.37, 95% CI: 1.16–4.85), non-exclusive breastfeeding (AOR = 2.26, 95% CI: 1.21–4.23), disposal of household garbage in a garbage can (AOR = 2.75, 95% CI: 1.32–5.69), mothers employment (AOR = 3.76, 95% CI: 1.22–11.53), rural residence (AOR = 2.21, 95% CI: 1.05–4.64), female sex (AOR = 2.11, 95% CI: 1.13–3.93), and having two or fewer children under five years of age (AOR = 8.92, 95% CI: 3.89–20.48). The identified factors such as water, sanitation and hygiene (WASH), inappropriate feeding behaviors, and socio-demographic are independently associated with acute diarrhea. Prospective or intervention studies are needed to establish causal-effects.