Hepatitis C virus, genome detection

Clinical significance
HCV is endemic worldwide and is a serious health problem. HCV is the main cause of chronic non-A, non-B hepatitis. The presence of antibodies to HCV indicates that a person may have been infected with HCV or may be able to transmit HCV infection. At least 170 million people worldwide are chronically infected with HCV.
HCV infection often causes no symptoms; however, most people exposed to HCV (over 80%) become chronically infected. In 20% of chronically infected people, the disease progresses to cirrhosis, liver failure and, in some cases, hepatocellular carcinoma or cholangiocarcinoma.
Despite the large number of people chronically infected with HCV, the annual incidence of HCV infections in developed countries has fallen considerably over recent decades. This fall has been attributed to better living standards and better public health measures within the medical community, such as screening of blood and blood products, the use of disposable needles and syringes, and the adoption of universal precautions throughout the health system.
The most common routes of HCV transmission are: blood transfusions, injecting drug use, piercing or tattooing (not carried out hygienically), exposure in healthcare settings, sexual intercourse, casual household transmission, assisted reproduction techniques, and transmission from mother to baby during pregnancy, birth or the post-natal period.
The HCV genome is made up of several functional regions: the core, the envelope (which includes the E1 and E2 regions) and the non-structural region (which includes the NS2, NS3, NS4 and NS5 regions).
Immunoassays for detecting antibodies to HCV use a combination of synthetic or recombinant proteins as antigens. If the screening test is positive, the result must be checked with a confirmatory test (Western blot).