Salivary HBsAg in hepatitis B infection

Hepatitis B surface antigen (HBsAg) was detected by solid phase radioimmunoassay (RIA) in mixed saliva of 15 out of 50 antigenemic patients. The salivary antigen was present in low titers for a short period of time in the acute stage of illness. Occult blood was detected in most mixed saliva samples. In parotid saliva neither HBsAg nor occult blood was found. Salivary HBsAg is probably due to admixture of blood or exudate.