07/25/2023
Because new HCV infections are usually asymptomatic, few people are diagnosed when the infection is recent. In those people who develop chronic HCV infection, the infection is often undiagnosed because it remains asymptomatic until decades after infection when symptoms develop secondary to serious liver damage.
HCV infection is diagnosed in 2 steps:
Testing for anti-HCV antibodies with a serological test identifies people who have been infected with the virus.
If the test is positive for anti-HCV antibodies, a nucleic acid test for HCV ribonucleic acid (RNA) is needed to confirm chronic infection and the need for treatment. This test is important because about 30% of people infected with HCV spontaneously clear the infection by a strong immune response without the need for treatment. Although no longer infected, they will still test positive for anti-HCV antibodies. This nucleic acid for HCV RNA can either be done in a lab or using a simple point-of-care machine in the clinic.
Innovative new test such as HCV core antigen are in the diagnostic pipeline and will enable a one-step diagnosis of active hepatitis C infection in the future.
After a person has been diagnosed with chronic HCV infection, an assessment should be conducted to determine the degree of liver damage (fibrosis and cirrhosis). This can be done by liver biopsy or through a variety of non-invasive tests. The degree of liver damage is used to guide treatment decisions and management of the disease.
Early diagnosis can prevent health problems that may result from infection and prevent transmission of the virus. WHO recommends testing people who may be at increased risk of infection.
In settings with high HCV antibody seroprevalence in the general population (defined as >2% or >5% HCV antibody seroprevalence), WHO also recommends blood donor screening, as well as focused or targeted testing of specific high-risk groups, including migrants from endemic regions, health-care workers, people who inject drugs (PWID), people in prisons and other closed settings, men who have s*x with men (MSM), s*x workers and HIV-infected persons.
WHO recommends that all adults have access to and be offered HCV testing with linkage to prevention, care and treatment services.
About 2.3 million people (6.2%) of the estimated 37.7 million living with HIV globally have serological evidence of past or present HCV infection. Chronic liver disease represents a major cause of morbidity and mortality among persons living with HIV globally.
