Detection of serum hepatitis B virus DNA using the polymerase chain reaction assay

We compared the sensitivity of the polymerase chain reaction (PCR) assay to that of slot blot hybridization for detecting hepatitis B virus (HBV) DNA in the serum of a chimpanzee infected with HBV and 52 patients. Also, we utilized a rapid PCR procedure for the detection: Viral DNA was released from virions by incubating serum with NaOH. After a primary PCR amplification, the sample was reamplified using a second set of primer pairs (PCR/PCR). In the chimpanzee, HBV DNA was detected 3 weeks earlier than the appearance of hepatitis surface antigen (HBsAg) and persisted for two weeks with antibody to HBsAg. Of the 14 chronic hepatitis B patients positive for both HBsAg and HBV e antigen (eAg), 9 were positive for HBV DNA by slot blot hybridization and all 14 by PCR. Also, of 9 patients positive for HBsAg and antibody to eAg, 2 were positive for HBV DNA by slot blot hybridization and 8 by PCR. Three of the 11 patients who had lost HBsAg during follow up examination of chronic hepatitis B were positive for HBV DNA by PCR, whereas none of them was positive by slot blot hybridization. Six patients who had recovered from acute hepatitis B more than one year ago and 12 cases who had had vaccination of HBV were negative for HBV DNA by PCR. This technique should yield valuable information on the biology of HBV.