The hepatitis C virus (HCV) is a blood‑borne virus that predominantly infects liver cells. In some people HCV infection can lead to cirrhosis of the liver, primary liver cancer or liver failure (Hepatitis C Trust). It is estimated that in 2014, about 214,000 people in the UK had chronic HCV infection (Public Health England 2014) and around half of those are undiagnosed because of long‑term asymptomatic infection (NHS Choices 2013).

HCV is usually transmitted through blood‑to‑blood contact. Around 90% of HCV infections diagnosed in the UK will have been acquired through injecting drugs. Around 50% of people in the UK who have injected drugs have antibodies against HCV (Public Health England, November 2014).

NICE's guidance on promoting and offering testing to people at increased risk of HCV infection identifies the following groups as being at increased risk:

  • People who have ever injected drugs.

  • People who had a blood transfusion before 1991 or blood products before 1986.

  • People born or brought up in a country with a 2% or greater prevalence of chronic hepatitis C.

  • Babies born to mothers infected with hepatitis C.

  • Prisoners, including young offenders.

  • Children and young people living in care homes.

  • People living in hostels for the homeless or sleeping on the streets.

  • HIV‑positive men who have sex with men.

  • People in close contact with someone known to be chronically infected with hepatitis C.

This list includes vulnerable people who are difficult to engage in health care. Commonly, people who are tested for HCV lose contact with clinical staff before they can receive their test results.

In the acute phase of HCV infection, symptoms may appear a few weeks after exposure to the virus. Symptoms include: high temperature; tiredness; loss of appetite; stomach pains and nausea; and sometimes jaundice (NHS Choices 2013). Many people infected with HCV have no symptoms, or have only symptoms that are minor and non‑specific, so they do not get tested for HCV or seek treatment. In 20% of people infected with HCV, the immune system will eliminate the virus without any medical care and they will have no further symptoms (unless they become re‑infected). In the remaining cases, HCV can persist inside the body for years. This is known as the chronic phase of HCV infection. The symptoms of chronic HCV can vary. Some people have very few symptoms, whereas for others it may significantly affect their quality of life.

Chronic HCV infection is associated with increased risk of irreversible liver damage (cirrhosis) and liver cancer. If HCV infection is detected before serious complications develop, treatments are available. Data from 2006 to 2011 showed that per year in England, only 3% of people with chronic HCV infection started treatment for HCV (PHE July 2014).

Public Health England's recommendations include increasing testing and awareness of HCV to help tackle infection (Public Health England 2014).