HBsAg carrier rate among institutionalised children from Phyathai Institute.

To identify the evidence supporting the horizontal transmission of hepatitis B virus, HBsAg carrier rate among institutionalised children is determined and compared to children of the same age-group from the well baby clinic, Ramathibodi hospital. The results of this study show that HBsAg is detected four times more frequently in institutionalised children than in children from a well baby clinic. The chance of becoming an HBsAg carrier increases with age and duration of stay in the institution.