Hepatitis B, C, and D virus infection showing distinct patterns between injection drug users and the general...

Hepatitis B, C, and D virus (HBV, HCV, and HDV) infections are known to be prevalent in injection drug users (IDUs); however, the relationship between the molecular epidemiologic features of hepatitis virus infection in high-risk individuals and the general population has not yet been established.

In total, 1049 IDUs and 672 individuals who underwent physical examinations at Chenzhou hospital, Hunan Province, China, were enrolled. HBV, HCV, and HDV infections were screened with serologic tests in both populations. HBsAg-positive, anti-HCV IgG-positive, and anti-HDV IgG-positive samples were further confirmed by polymerase chain reaction, quantitative polymerase chain reaction, and DNA sequencing.

Significantly higher HBV (21.54 vs 16.52%, P = 0.01), HCV (45.95% vs 1.34%, P < 0.001), and HDV (5.62% vs 0.30%, P < 0.001) infections were detected in IDUs compared with the general population. The dual infection of HBV/HCV or HBV/HDV was also significantly higher in IDUs than in the general population. HBV genotype B and HDV genotype II were dominants in both populations. HCV infection showed genotype 6a (49.52%) dominant in IDUs, but genotype 1b accounted for 50% infection, which was followed by genotype 6a (33.33%) in the general population. Higher viral loads were associated with HBV genotype B and HCV genotype 6a compared with non-dominant genotypic infections.

HBV and HDV infections shared similar patterns by IDUs and the general populations, and HCV infection exhibited distinct features between two populations. Our results suggest different molecular epidemiologic characteristics of HBV, HCV, and HDV infection in two populations.