ABSTRACT
In order to investigate probable intrafamilial prevalence and transmission routes of HBV infection and we studied 61 families seen in ambulatory clinic between July 93 and January 94, and at least one member of every family was HBsAg positive HBV markers were testedin 251 members of 61 families. The prevalance of HBsAg and total Anti-HBc/Anti-HBs was found 19.4 %and 41 %, respectively. The transmission rates of HBV infection were high, if the mother was HBsAg positive. In conclusion, there is a nonparenteral-horizantal transmission as well as a vertical transmission in families.