Evidence of a 1985-1987 outbreak of acute and chronic hepatitis in Egypt caused by a mutant hepatitis-B virus detected by spot-DNA hybridization test.

Sera from 65 acute and 113 chronic sporadic hepatitis were screened for serological markers of hepatitis-B virus (HBV) and hepatitis delta virus (HDV) and for HBV-DNA. The enzyme linked immune sorbent assay (ELISA) and dot-DNA hybridization tests were used. Two HBV-DNA probes and their labelling systems (biotin, radiolabelling with 32P and digoxigenin) were compared for sensitivity and specificity. The 65 acute sera had serological parameters of HBV infection in 38 (58%) when all these sera were HBsAg, IgM anti HBcAg positive plus HBeAg presence in 11/38 sera. Some of the acute sera had markers of acute HBV and HDV coinfection in 14 and superinfection in 13. Thus HBV with HDV represented 27 (41.5%) of the acute hepatitis in this study. Correlation of these serological markers with dot-DNA hybridization results showed that serum HBV-DNA was present in 36/38 (94.7%) of the acute HBV infection. In the case of acute HBV+HDV positive antigenemia 4/6 had serum HBV-DNA while 10/21 of acute HBV with anti-deltaV. IgM had serum HBV-DNA. There were four cases that gave HBV-DNA positivity in sera without combination of HBV markers suggesting infection with "mutant" HBV. In the chronic hepatitis sera there were markers of HBV past infection (IgG anti HBc in 63/113 and IgG anti HBs in 36/113). Yet, among these sera there was HBV-DNA positive signals (20/63 and 17/36) respectively. Analysis of some of these HBV markers also suggested infection with "mutant" HBV.