Clinico-epidemiological study of GBV-C/HGV infection in Tokyo metropolitan, and Nanjing and Yanbian cities in the People's Republic of China

In the present study, we compared the molecular epidemiology of GBV-C/HGV co-infection and the clinical profiles in patients diagnosed with either type B or type C hepatitis virus infection from Nanjing in Southeast China and Yanbian in Northeast China, with those at the Nihon University Hospital in Tokyo. The patients included 97 men in Nanjing, 66 men and women in Yanbian, and 249 men and women at the Nihon University Hospital. GBV-C/HGV RNA was detected using reverse transcriptase polymerase chain reaction as described by Abe et al. The prevalence of GBV-C/HGV co-infection in Nanjing, Yanbian, and Tokyo was 18.8, 23.3, and 3.5% in type B liver diseases, respectively, and 3.6, 11.1, 7.3% in type C liver diseases, respectively. A comparison of background factors between GBV-C/HGV RNA-positive and -negative patients revealed no significant differences in any parameter between Nanjing, Yanbian, and Tokyo. A phylogenic tree analysis of nucleotide sequences showed that the Nanjing strain was closely related to the Shanghai, Hong Kong, and Tokyo isolates, while the Yanbian isolate was closely related to the Korean, Mongolia, and Tokyo strains. These isolates were classified to the East Asian type of genotype 3. The results of the phylogenic tree analysis suggests that the GBV-C/HGV isolates from China and Japan have a common origin. Therefore, the prevalence of GBV-C/HGV infection may be geographically determined, irrespective of racial differences.