Hepatitis B virus infection and genotype in asymptomatic people from 10 ethnic groups in Yunnan, China.

AIM: To evaluate the infection and genotype distribution of hepatitis B virus (HBV) in ethnic groups in Yunnan, China. METHODS: Two thousand five hundred and eighty-four asymptomatic local people from 10 ethnic groups were investigated in Yunnan, China. Infection and genotype distribution were evaluated by serological and genetic methods. Genotyping was verified by sequencing. Ethnic genotype distribution was compared by proportion test. RESULTS: Four types of infection model based on HBV serum markers were identified, and the average HBV infection rate was 5.7% in those asymptomatic local people. The genotype prevalence was 59.6% for B, 21.1% for C and 19.3% BC; subgenotypes Ba, Cs and Ce were identified in this study. Hepatitis B surface antigen-positive rate and the proportion of genotype B were significantly lower in ethnic groups with a northern origin compared to those with a southern origin (50% vs 73.9%, P = 0.037; 4.2% vs 10.5%, P = 0.000). CONCLUSION: Genotype B is dominant and genotype BC has high occurrence in asymptomatic local ethnic groups in Yunnan. HBV infection status and genotype distribution may associate with ethnic origin.