Risk factors for Hepatitis A virus infection in Mongolia: A population based case control study

Viral hepatitis is one of the major public health problems in Mongolia and hepatitis A virus infection represents a substantial proportion. However, little is known about the social and behavioral factors that influence the transmission of hepatitis A virus in Mongolia.

We conducted a population based case control study to investigate the risk factor patterns for hepatitis A among children residing in a capital city-Ulaanbaatar. A total of 85 confirmed cases of hepatitis A were selected from the National Center for Communicable Diseases and 400 controls were selected from primary schools of same districts as cases. After obtaining informed consent, structured questionnaire for parents and children were used for data collection to identify risk factors for hepatitis A transmission.

Univariate analyses showed that lodging types (living in a traditional lodging “Ger”) (OR: 3.02; 95% confidence interval [CI]: 1.61-5.63), drinking unboiled water (OR: 3.07; 95%CI: 1.90-4.97), having toilet and sink that connected to the centralized system (OR: 0.37; 95%CI: 0.19-0.67 and OR:0.34; 95%CI: 0.18-0.61, respectively) and having a hepatitis A patient in a family (OR:32.48; 95%CI: 10.80-97.72) were significantly associated with hepatitis A. However, these results were attenuated in a multivariate regression analysis, and only household transmission through contact with hepatitis A patient (adjusted odds ratio [AOR] 22.31; 95% CI: 6.91-72.06) and drinking unboiled water (AOR=2.48; 95%CI: 1.42-4.31) remained significant risk factors for hepatitis A among children.

The results of this study underline the importance of household and behavioral risk factors for hepatitis A among Mongolian children