Viral hepatitis in the Bhutanese population: preliminary results of a seroepidemiological investigation.

A seroepidemiological study of the prevalence of markers related to the most common forms of viral hepatitis was carried out in Bhutan on 1,666 healthy people of both sexes, from the general population. A group of 440 pregnant women were screened separately. Our results suggest that in Bhutan, hepatitis A and hepatitis B are widespread, while there is a low prevalence of hepatitis C and E. Anti-HAV (anti-hepatitis A virus) was found in all 171 tested subjects over 12 years of age, and anti-HBc (anti-hepatitis B core antigen) in 63.1% of 1,666 tested people. On the other hand, anti-HEV proved positive in 2.0% of 257 tested subjects, and anti-HCV in only 1.3% of 611 tested subjects. Hepatitis B surface antigen (HBsAg) was found in 5.9% of the sample from the general population (5.2% in children, 5.6% in young people and 6.3% in adults) and in 5.4% of the pregnant women. Furthermore, 29.1% of HBsAg-positive pregnant women were HBeAg- and HBV DNA-positive, too. Comparing the pregnant women's prevalence data to those found in children, we suggest that the main route of HBV transmission in the Bhutanese population is vertical, from mother to child; this finding is important for the implementation of a correct anti-HBV vaccination strategy in Bhutan.