SEROEPIDEMIOLOGY OF HEPATITIS-B, HEPATITIS-C AND HEPATITIS-DELTA VIRUSES IN TUNISIA

Serum samples from 33363 healthy people in Tunisia have been tested fo r serological markers of hepatitis B, C and delta viruses (HBV, HCV an d HDV). Hepatitis B surface antigen (HBsAg) was detected in 6.5% of se ra. The overall seroprevalence of HBV was 37.5 %. Vertical and perinat al transmission of HBV in the first 3 months of life occurred in only 0.4% of 177 mother and child pairs. HBV seroprevalence was 10.7% in in fants under 5 years old and increased with age rapidly till 25 years o f age and then more slowly in adulthood, reaching 54% for people aged over 40 years. HBsAg seropositivity varied throughout the country, ran ging from 3% to 13% with higher prevalences in the south and central-w est regions. Overall seroprevalences for HDV and HCV were 17.7% and 0. 4%, respectively. HDV superinfection occurred later than HBV and incre ased with age in parallel with HBV. Overall, HCV and HBV infections ha d different geographical distributions throughout the country. The stu dy confirmed the high prevalence of HBV infection in Tunisia; it occur s mainly in children and teenagers, and vertical and perinatal transmi ssion of HBV does not appear to be significant. HDV superinfection is quite common in Tunisia and occurs in almost 44% of individuals infect ed with HBV. In contrast, seroprevalence of HCV in the Tunisian genera l population was low (0.4%). These results indicate differences in the distribution of the viruses and/or different routes of transmission.