March 9, 2013
The hepatitis C virus (HCV) spreads primarily through contact with infected blood. Because HCV is a very small virus, tiny amounts of blood -- too small to be seen -- can transmit hepatitis C. In used syringes, blood can be infectious for three weeks. The virus can survive in dried blood spills for up to four days.
Hepatitis C was not discovered until 1989. Until 1990, there was no way to test blood for HCV. Many people got HCV from blood transfusions or blood products, such as those used by hemophiliacs. In the early 1990s, blood banks began to test for hepatitis C. Where this is done, new infections are not occurring. However, if blood is not tested, or if medical equipment is not sterilized, HCV infection can occur.
Kidney dialysis patients are at risk for HCV if infection control procedures at dialysis facilities are not adequate.
Normal household contact does not spread hepatitis C. It is not transmitted by hugging, kissing, or eating or drinking from a shared glass, fork, knife, or plate.
However, there can be some risk in sharing household items that might have tiny, invisible amounts of blood on them. This includes shaving razors, fingernail clippers and toothbrushes.
The main way hepatitis C is transmitted is through drug injection. Some studies found that as many as 90% of injection drug users are infected with HCV. Because so many injection drug users have are infected with hepatitis C, and you cannot tell by looking at someone if they're infected, you should be very careful if you inject drugs with anyone else -- don't share anything with another person.
Sharing syringes for injection is the riskiest activity for getting hepatitis C. You can also get hepatitis C from other materials used to inject drugs. This includes cookers, cottons, filters, syringes and ties. Amounts of blood too small to see can be enough to transmit hepatitis C, so it is important to never share any materials used to inject drugs.
Better public access to clean needles reduces the spread of hepatitis. In some states, adults can purchase new syringes in pharmacies without a prescription. Some communities have started needle exchange programs to give free, clean syringes to people so they won't need to share. The North American Syringe Exchange Network has a web page listing several needle exchange programs at www.nasen.org/.
Tattooing can transmit HCV if equipment, ink or even inkwells are shared. These unsafe practices are especially likely if tattoos are done on the street, or in prison.
If you decide to get a tattoo, check the safety procedures. These include:
HCV can be spread from a mother to her child during pregnancy or delivery, although this only happens in about 1 out of 30 cases. This is called "vertical transmission." A baby can also be infected by drinking an infected woman's breast milk if mother's breasts (nipples) are cracked and bleeding.
Exposure to HCV-infected blood can cause infection through an accidental contact with a needle, or if the blood comes into contact with an open cut or sore, or with the eyes. Healthcare workers should follow standard procedures to avoid contact with possibly infected blood.
HCV is not commonly spread through sexual activity. However, sexual practices that cause even minor bleeding can spread HCV. Vigorous intercourse, fisting, anal sex or other activities that draw blood can transmit HCV.
People who have a sexually transmitted disease such as HIV are more likely to transmit hepatitis C through sexual activity. Any open sores, such as those caused by herpes or syphilis, increase the risk of transmission.
Sexually transmitted HCV is spreading among HIV positive men who have sex with men (MSM). Risk factors include sharing sex toys, having multiple partners, rougher and longer anal intercourse, fisting, and anal sex after rectal surgery.
Hepatitis C might not cause any symptoms. If you think you have been exposed, you should get tested.
The main way HCV is spread is through contact with infected blood. Even tiny amounts of blood, too small to see, can transmit HCV. Injection drug users are at high risk of HCV infection. Tattooing and sexual activity carry some risk of HCV transmission. HCV-infected pregnant women can pass the infection to their new babies, although the risk is low (about 3%).