Characteristics of hepatitis C virus infection and genotype distribution among entry travelers at Tengchong Port

Objective To investigate the characteristics of epidemic and genotype/subtype distribution of hepatitis C virus (HCV) among entry travelers at Tengchong port, to provide references for HCV prophylaxis and treatment. Methods A total of 54 serum samples were collected from anti-HCV positive travelers at Tengchong port from June 2009 to June 2016. HCV NS5B gene was amplified using reverse transcription polyonerase chain reation (RT-PCR) and subsequently sequenced. Based on the obtained sequences and retrieved reference sequences, phylogenetic analysis was conducted to determine HCV genotype/subtype. Results HCV infection rate among entry travelers at Tengchong ports was 0.45%(54/12 059). Forty-five samples were successfully genotyped. Phylogenetically, HCV genotype 3b was revealed to be the predominant subtype (28.89%, 13/45) in this population, followed by genotype 6n (20.0%, 9/45), genotype 1b (17.78%, 8/45), genotype 3a (13.33%, 6/45), genotype 2a (11.11%, 5/45), genotype 1a (2.22%, 1/45) and genotype 6a (2.22%, 1/45). The major genotype in Myanmar travelers was genotype 6, while in Chinese population, genotype 1 predominated. Genotype 6 in the population showed close phylogenetic relationship with strains prevalent in China and Southeast Asia. Genotype 3 was closely clustered with strains prevalent in China. Conclusions The distribution of HCV genotypes among entry travelers at Tengchong port is impacted by HCV epidemic strains both in Yunnan province and neighboring regions. This population serves as a transmitting media which may influence the epidemiological characteristics of HCV in Tengchong and neighboring areas. Key words: Hepatitis C virus; Epidemiology, molecular; Entry travelers