There are numerous connections between hepatitis C and HIV (human immunodeficiency virus), but distinctions between the two viruses must also be understood. These are separate viruses; hepatitis C principally attacks the liver, and HIV can have a systemic effect. In certain populations, such as among intravenous drug users or people with blood diseases that require frequent blood products, the two viruses may occur together often. In other populations, such as the population of HIV infected men who contracted HIV through homosexual sexual activity, the risk of also contracting hepatitis C is approximately the same as for heterosexual males with the virus. Another important connection involves what occurs when these viruses are concomitant.
The biggest link between hepatitis C and HIV is observable in the population of people who use intravenous illegal drugs. In this group, there is better than a 50% chance, and possibly as high as a 90% probability that people infected with one virus will also be infected with the other. Part of this is due to the way both viruses can easily spread and the behavior of those who may use intravenous drugs. Both viruses can spread through direct contact with the infected blood of someone else, and when needle sharing, which is still common, is part of drug use practice, the likelihood of acquiring both viruses becomes very high. Using needle exchange programs may help reduce risk, but people who have shared needles in the past are encouraged to get tested for hepatitis C and HIV.
Though male homosexual sexual activity greatly increases risk for HIV, it does not significantly increase risk for hepatitis C. There is some risk, and about 3-5% of people may contract hepatitis C from homosexual or heterosexual unprotected sex. Generally, the greatest risk of hepatitis C comes from direct contact with infected blood or products made from that blood.
The differences in how hepatitis C and HIV are contracted suggests that efforts to prevent hepatitis C need to be principally directed at people who are using intravenous drugs. Efforts to prevent HIV in this population are also required. For HIV infection alone, intervention and education should still focus on emphasizing safer sex practices for both homosexual and heterosexual populations.
Work to prevent hepatitis C and HIV from occurring are greatly needed, since having both viruses may complicate treatment and interfere with health. People with HIV are more vulnerable to the negative effects of hepatitis C. They are likely to have more liver damage and scarring sooner. Consequently, hepatitis C-related deaths and hospitalizations are higher in the HIV population. Hepatitis C may not cause AIDs, though there is some debate on this point, but it may cause death before AIDs occurs.
People with hepatitis C pose risk to uninfected partners with HIV. It is important to minimize potential contact with infected blood. This means employing safer sex practices, and avoiding sharing things like needles, razors, or toothbrushes that could contain traces of infected blood.