Background and aims: One-third of all child deaths in this country are caused by diarrhea. The burden of the disease appears to be increasing in recent years in Bangladesh. This study aimed to analyze the prevalence of diarrhea and identify the factors contributing to diarrheal diseases among children aged 0-5 years in Bangladesh from 2006 to 2019, to understand the recent increase in this serious health issue.

Methods: In this study, using the data from the Multiple Indicator Cluster Survey (MICS), a total of 31,566, 23,402, and 24,686 children under five were included from, 2006, 2012, and 2019, respectively. Logistic regressions were applied to analyze the changes in factors influencing childhood diarrhea.

Results: The results revealed a decline in diarrhea prevalence from MICS 2006 (7.1%) to MICS 2012 (3.9%). However, there was a sharp increase to 6.9% in MICS 2019. Notably, children aged 12-23 months exhibited consistently 2.22 times (adjusted odds ratio (AOR) = 2.22, 95% confidence interval (CI: 1.86-2.65), 5.24 times (CI: 2.51-10.95) and 3.36 times (CI: 2.67-4.22) higher likelihood of experiencing diarrhea compared to the older age group (48-59 months) in MICS 2006, 2012 and 2019, respectively. The mother's educational background also played a role, in MICS 2006, 2012, and 2019, children whose mothers had no or incomplete primary education had 1.48 (CI: 1.18-1.86), 1.07 (CI: 0.76-1.50), and 1.34 (CI: 1.06-1.69) times higher chances of diarrhea compared to children of mothers with secondary complete or higher education.

Conclusion: Underweight status, geographical division, household wealth status, and unimproved and shared toilet facilities emerged as contributing factors of diarrhea among children aged 0-5 years. The findings underscore the importance of child nutrition, basic hygiene practices, and special care during the rainy season to mitigate the under-five mortality rate associated with diarrhea.