Hepatitis B and hepatitis D virus infections in the Central African Republic, twenty-five years after a fulminant hepatitis outbreak, indicate continuing spread in asymptomatic young adults. HDV and HBV in CAR

Hepatitis delta virus (HDV) increases morbidity in Hepatitis B virus (HBV)-infected patients. In the mid-eighties, an outbreak of HDV fulminant hepatitis (FH) in the Central African Republic (CAR) killed 88% of patients hospitalized in Bangui. We evaluated infections with Hepatitis B and Hepatitis D viruses among students and pregnant women born at the end of the FH outbreak, 25 years after the fulminant hepatitis (FH) outbreak to determine (i) the prevalence of HBV and HDV infection in this population, (ii) the clinical risk factors for HBV and/or HDV infections, and (iii) to characterize and compare the strains from the FH outbreak in the 1980s to the 2010 HBV–HDV strains.We performed a cross sectional study with historical comparison on FH-stored samples (n=179) from 159 patients and dried blood-spots from volunteer students and pregnant women groups (n=2171). We analyzed risk factors potentially associated with HBV and HDV infections such as surgery, dental extraction, blood transfusion, IVDU, tattooing, use of sharp tool, alcohol intake and sexual risk. Serological and viral markers were characterized in 2162 individuals. Previous HBV infection (presence of anti-HBc) occurred in 349/1296 students (26.9%) and 182/866 pregnant women (21.0%)(p=0.002), including 114 students (8.8%) and 70 pregnant women (8.0%) who were also HBsAg-positive (p=0.539). HDV infection occurred more frequently in pregnant women (n=13; 18.8%) than students (n=6; 5.3%) (p=0.004). Infection in childhood was probably the main HBV risk factor. The risk factors for HDV infection were age (p=0.040), transfusion (p=0.039), absence of condom use (p=0.049) and a tendency for tattooing (p=0.055). HBV-E and HDV-1 were highly prevalent during both the FH outbreak and the 2010 screening project. Due to conservation condition, even using many attemps, we could only obtain partial HDV genome amplification representing 25% of the full length for historical samples. The HDV-1 mid-eighties FH-strains did not form a specific clade and were affiliated to two different HDV-1 African subgenotypes, one of which included the 2010 HDV-1 strains.In the Central African Republic, these findings indicate a high prevalence of previous and current HBV-E and HDV-1 infections both in the mid-eighties fulminant hepatitis outbreak and among asymptomatic young adults in 2010, and reinforce the need for universal HBV vaccination and the prevention of HDV transmission among HBsAg-positive patients through blood or sexual routes.