transmission
Last reviewed 04/2022
Hepatitis C virus is mainly transmitted through blood but is also detected in other body fluids as well (1).
Transmission does not occur from casual contact (holding hands, hugging or kissing or through sharing toilets, crockery and kitchen utensils) and appears to require transfer of predominantly either blood or sexual transmission
- in the UK, the people
at greatest risk of contracting hepatitis C infection are injecting drug-users
that share blood-contaminated needles, syringes or other equipment
- "... major route of HCV transmission in the UK is believed to be by sharing equipment for injecting drug use, mainly via blood-contaminated needles and syringes. Spoons, water and filters may also be vehicles of infection. It is estimated that between 30 to 80% of all current injectors have been infected with hepatitis.The corresponding rate for past injectors is thought to be higher. Sharing pipes for smoking and straws for snorting can also transmit HCV, particularly if there are cuts or damage to the lips or nose and blood present..." (1)
- sexual transmission is rare compared to that seen with HBV and other sexually transmitted agents but may be increased 5-fold in patients co-infected with HIV (2)
- vertical
transmission from mother to foetus may occur:
- either in utero or during the time of birth (1) at a rate of about 6% from mother to child if the mother is an HCV carrier (3)
- this rate increases to 15-20% if the mother is co infected with HIV (1)
- association between breastfeeding and transmission of infection has not been proven
- if the mother is HCV RNA negative, transmission of infection will not occur (1)
- less common sources of infection include
- tattooing or body piercing with contaminated equipment
- exposure to the virus during medical and dental procedures, blood transfusions and circumcisions especially in countries where hepatitis C is common and hygiene poor (1,4)
- a small amount of transmission may be seen amongst people sharing items contaminated with blood (toothbrushes, razors and other personal toiletries) (1)
- in the UK blood products were also a potential source of infection until the introduction of viral inactivation of blood products (in 1986) and screening of blood donors for hepatitis C (in 1991)
- less than 2% of needle-stick injuries from a hepatitis C-positive source result in infection (4)
- there is a higher risk if the injuries are deep and from blood filled needles (1)
Up to 85% of patients exposed to hepatitis C virus progress to develop chronic hepatitis C virus infection (2).
Reference:
- (1) Royal College of General Practitioners (RCGP) 2007. Guidance for the prevention, testing, treatment and management of hepatitis C in primary care .
- (2) NICE (October 2000). Guidance on the use of Ribavirin and Interferon Alpha for Hepatitis C.
- (3) NICE (August 2006). Guidance on use of peginterferon alfa and ribavirin for the treatment of mild chronic hepatitis C
- (4) Drug and Therapeutics Bulletin 2005; 43 (3):22-24