High circulation of hepatitis B virus (HBV) precore mutants in Tunisia, North Africa

Hepatitis B Virus (HBV) e antigen (HBeAg), HBV DNA and precore mutations af fecting HBeAg expression during active replication were studied in 72 Tunis ian hepatitis B surface antigen (HBsAg) positive individuals: 30 asymptomat ic carriers of the virus, 37 with chronic hepatitis and 5 with acute hepati tis. HBV DNA was detected in 44 patients, but only 20% of them expressed HB eAg. Precore mutant strains, with mutations at position 1896 or at position s 1896 and 1899, were detected by PCR-hybridization in 86 and 36% of patien ts, respectively. Wild-type strains were detected in 54% of patients. Preco re mutants were found in chronically and in acutely infected individuals, i n patients with severe and asymptomatic infections, in HBeAg positive as we ll as HBeAg negative individuals. These results show the high frequency of HBV precore mutants in Tunisia.