Epidemiology of hepatitis C virus infection.

Hepatitis C is a global health problem, with an estimated 71·1 million individuals chronically infected worldwide, accounting for 1% (95% uncertainty interval: 0.8-1.1) of the population. HCV transmission is most commonly associated with direct exposure to blood, via blood transfusions, unsafe health-care-related injections and intravenous drug use. The global incidence of HCV was 23·7 cases per 100 000 population (95% uncertainty interval 21·3-28·7) in 2015, with an estimated 1·75 million new HCV infections diagnosed in 2015. An estimated 2.3 millions of people living with HIV have serological markers of past or current HCV infection. Globally, the most common infections are with HCV genotypes 1 (44% of cases), 3 (25% of cases), and 4 (15% of cases). Approximately 10-20% of individuals who are chronically infected with HCV develop complications, such as cirrhosis, end stage liver disease, and hepatocellular carcinoma over a period of 20-30 years. Direct-acting antiviral therapy is curative, dramatically reducing the mortality related to HCV and the need for liver transplantation, but it is estimated that only 20% of individuals with hepatitis C know their diagnosis, and only 15% of those with known hepatitis C have been treated. Increased diagnosis and linkage to care through universal access to affordable point-of-care diagnostics and pangenotypic direct-acting antiviral therapy is essential to achieve the WHO 2030 elimination targets.