Characteristics of HBsAg subtypes distribution in Beijing area

This paper reports that 300 HBsAg positives were distributed in 262 families. 14 of the 262 families had two or more HBsAg positives. In the 14 families, 7 showed the same subtype HBsAg, probably due to HBV infection from family source. Another 7 families showed HBsAg of different subtypes, definitely due to infections from the community.