Once exposed to air, any blood left behind on a razor blade dries out. This breaks down the environment that HIV may have been contained in. The traces of blood that might be left behind on a blade are small, accelerating the drying process.
It's also important to know is that whereas scientists have found blood on razor blades to pose a risk for hepatitis transmission, it has never been an issue in relation to HIV. For hepatitis C, there have been cases where people living in the same household have shared razor blades and have passed on hepatitis in this way. This has never happened with HIV.
As there are other bacterial and viral infections, including hepatitis, which can occasionally be transmitted through sharing razors, it may be prudent to avoid doing so -- but out of a general concern for hygiene, rather than a specific concern about HIV.
More on HIV Transmission Risks at TheBody.com
To find out more about how HIV is passed on, we recommend the following articles:
In addition, our Q&A experts sometimes address questions about transmission risks in our "Ask the Experts" forums. Here are some of those questions and our experts' responses:
- HIV survival outside body in steam room
I had a cut on my foot when I was at a bathhouse. I think I stepped on some semen on the floor -- does HIV survive in this kind of warm, wet environment?
- Straight razors at the barbershop. So worried!
Last Friday I had a shave at a barbershop but I didn't notice the barber changing the razor or sterilizing it.