Hepatitis C is found worldwide with some countries having chronic infection rates as high as 5% and above.. The main mode of transmission in these countries is attributed to unsafe injections using contaminated equipment.
The hepatitis C virus is most commonly transmitted through exposure to infectious blood. This can occur through:
- receipt of contaminated blood transfusions, blood products and organ transplants;
- injections given with contaminated syringes and needle-stick injuries in health-care settings;
- injection drug use;
- being born to a hepatitis C-infected mother.
Hepatitis C may be transmitted through sex with an infected person or sharing personal items contaminated with infectious blood, but these are less common.
Hepatitis C is not spread through breast milk, food or water or by casual contact such as hugging, kissing and sharing food or drinks with an infected person.
The incubation period for hepatitis C is 2 weeks to 6 months. Following initial infection, approximately 80% of people do not exhibit any symptoms. Those who are acutely symptomatic may exhibit fever, fatigue, decreased appetite, nausea, vomiting, abdominal pain, dark urine, grey-coloured faeces, joint pain and jaundice (yellowing of skin and the whites of the eyes).
About 75–85 % of newly infected persons develop chronic infection and 60–70% of chronically infected people develop chronic liver disease; 5–20% develop cirrhosis and 1–5% die from cirrhosis or liver cancer. In 25% of liver cancer patients, the underlying cause is hepatitis C.
Diagnosis of acute infection is often missed because a majority of infected people have no symptoms. Common methods of antibody detection cannot differentiate between acute and chronic infection. The presence of antibodies against the hepatitis C virus indicates that a person is or has been infected. The hepatitis C virus recombinant immunoblot assay (RIBA) and hepatitis C virus ribonucleic acid (RNA) testing are used to confirm the diagnosis.
Diagnosis of chronic infection is made when hepatitis C virus RNA is identified by nucleic acid testing in a person with antibodies against hepatitis C virus. Specialized tests are often used to evaluate patients for liver disease, including cirrhosis and liver cancer.