The hepatitis C virus (HCV) causes both acute and chronic infections. Acute HCV infections are usually asymptomatic and most do not lead to life-threatening diseases. About 30% (15-45%) of infected people shed the virus spontaneously within 6 months of infection without any treatment. The remaining 70% (55–85%) of people will develop chronic HCV infection. Of those with chronic HCV infection, the risk of cirrhosis ranges from 15% to 30% within 20 years.
The hepatitis C virus is a blood-borne virus. It is most commonly transmitted through:
- improper reuse or sterilization of medical equipment, especially syringes and needles in healthcare settings;
- transfusion of unselected blood and blood products; Y
- the use of injection drugs through the shared use of injection equipment.
HCV can be transmitted from an infected mother to her baby and through sexual practices that lead to blood exposure (eg, people with multiple sexual partners and between men who have sex with men); however, these modes of transmission are less common. Hepatitis C is not spread through breast milk, food, water, or casual contact such as hugging, kissing, and sharing food or drink with an infected person.
The incubation period for hepatitis C varies from 2 weeks to 6 months. After the initial infection, about 80% of people do not have any symptoms. Those who have acute symptoms may present with fever, fatigue, decreased appetite, nausea, vomiting, abdominal pain, dark urine, pale stools, joint pain, and jaundice (yellowing of the skin and whites of the eyes).
Tests and diagnosis
Because new HCV infections are often asymptomatic, few people are diagnosed when the infection is recent. In those who develop chronic HCV infection, the infection often goes undiagnosed because it remains asymptomatic until decades after infection when symptoms develop as a consequence of severe liver damage.
HCV infection is diagnosed in 2 steps:
- Testing for anti-HCV antibodies with a serologic test identifies people who have been infected with the virus.
- If the test is positive for 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 clear the infection spontaneously through a strong immune response without the need for treatment. Even if they are no longer infected, they will still test positive for HCV antibodies. This HCV RNA nucleic acid can be made in a laboratory or using a simple machine at the point of care in the clinic.
After a person has been diagnosed with chronic HCV infection, an evaluation should be done to determine the degree of liver damage (fibrosis and cirrhosis). This can be done through a liver biopsy or through a variety of non-invasive tests. The degree of liver damage is used to guide treatment decisions and disease management.
Early diagnosis can prevent health problems that can 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 recommends that all adults have access to and be offered HCV testing with connection to prevention, care and treatment services.
About 2.3 million people (6.2%) of the estimated 37.7 million people living with HIV worldwide have serologic evidence of past or present HCV infection. The chronic liver disease represents a major cause of morbidity and mortality among people living with HIV worldwide.
A new HCV infection does not always require treatment, as the immune response of some people will clear the infection. However, when HCV infection becomes chronic, treatment is necessary. The goal of hepatitis C treatment is to cure the disease.
WHO recommends treatment with pan-genotypic direct-acting antivirals (DAAs) for all adults, adolescents, and children under 3 years of age with chronic hepatitis C infection. DAAs can cure most people with HCV infection and the duration of treatment is short (usually 12 to 24 weeks), depending on the absence or presence of cirrhosis. In 2022, the WHO included new recommendations for the treatment of adolescents and children using the same pan-genotypic treatments used for adults.
Pangenotypic DAAs remain expensive in many high- and upper-middle-income countries. However, prices have fallen dramatically in many countries (mainly low- and lower-middle-income countries) due to the introduction of generic versions of these medicines. The most widely used and inexpensive pan-genotypic DAA regimen is sofosbuvir and daclatasvir. In many low- and middle-income countries, the curative course of treatment is available for less than $50.
There is no effective vaccine against hepatitis C, so prevention depends on reducing the risk of exposure to the virus in healthcare settings and in populations most at risk. This includes people who inject drugs and men who have sex with men, particularly those infected with HIV or those taking HIV pre-exposure prophylaxis.
WHO-recommended primary prevention interventions include:
- safe and appropriate use of injections for health care;
- safe handling and disposal of sharps and waste;
- provision of comprehensive harm reduction services to people who inject drugs;
- tests of donated blood for HBV and HCV (as well as HIV and syphilis);
- training of health personnel; Y
- prevention of exposure to blood during sexual intercourse.