Global epidemiology and genotype distribution of the hepatitis C virus infection

The treatment of chronic hepatitis C virus (HCV) infection has the potential to change significantly over the next few years as therapeutic regimens are rapidly evolving. However, the burden of chronic infection has not been quantified at the global level using the most recent data. Updated estimates of HCV prevalence, viremia and genotypes are critical for developing strategies to manage or eliminate HCV infection. To achieve this, a comprehensive literature search was conducted for anti-HCV prevalence, viraemic prevalence and genotypes for all countries. Studies were included based on how well they could be extrapolated to the general population, sample size and the age of the study. Available country estimates were used to develop regional and global estimates. Eighty-seven countries reported anti-HCV prevalence, while HCV viraemic rates were available for fifty-four countries. Total global viraemic HCV infections were estimated at 80 (64-103) million infections. Genotype distribution was available for ninety-eight countries. Globally, genotype 1 (G1) was the most common (46%), followed by G3 (22%), G2 (13%), and G4 (13%). In conclusion, the total number of HCV infections reported here are lower than previous estimates. The exclusion of data from earlier studies conducted at the peak of the HCV epidemic, along with adjustments for reduced prevalence among children, are likely contributors. The results highlight the need for more robust surveillance studies to quantify the HCV disease burden more accurately.