Hepatitis C: risk groups, testing and treatment

What it is

HCV is an RNA flavivirus and the most prevalent bloodborne infection in the West; it is also described as the most common chronic bloodborne pathogen in the United States and a leading cause of complications of chronic liver disease. Its acute infection is asymptomatic, so it manifests instead as chronic liver disease. The incubation period is 6 to 9 weeks. After an acute infection 15% to 45% of patients will clear the virus, and 55% to 85% will develop chronic hepatitis C, which can cause cirrhosis and is a risk factor for HCC.

Causes and risk

High-risk groups include injection drug users, recipients of blood transfusions before 1992, and those with HIV or an STI. Apart from those groups, test for HCV in patients with chronic liver disease, and in patients with vasculitis, cryoglobulinemia, GN, or porphyria cutanea tarda.

Who to screen is given differently in two places. The U.S. Preventive Services Task Force goes by year of birth: screening for HCV infection in persons at risk for infection, and one-time screenings for adults born between 1945 and 1965 (Grade B recommendation), the years in which about 75% of those living with HCV were born, against an anti-HCV prevalence of roughly 1.6%. The CDC recommendations are universal: hepatitis C screening at least once in a lifetime for all adults aged 18 years and older, and for all pregnant women during each pregnancy, except in settings where the prevalence of HCV RNA-positivity is less than 0.1%. The CDC list is the one that adds one-time hepatitis C testing regardless of age or setting prevalence among people with recognized conditions or exposures: people with HIV; people who ever injected drugs and shared needles, syringes or other drug preparation equipment; people with selected medical conditions, including those who ever received maintenance hemodialysis and those with persistently abnormal ALT levels; and children born to mothers with HCV infection.