HIV

Q: Is it safe for an HIV-positive person to have unprotected sex with another HIV-positive person?

We assume you are referring whether you can be "re-infected" or "superinfected" with another strain of HIV. While the research on this question is not 100% clear, there are only rare reports of someone who already has HIV getting another HIV infection that damages their health.

It is true that a person who's been infected with one strain can become infected with a second strain when exposed to it (such as through unprotected sex), but this appears to be quite uncommon. A person whose first HIV infection is relatively recent may be more susceptible to infection with a second strain. Someone may become sicker once the second strain of the virus enters the system. This happens because the new strain may be more difficult for the immune system to control, or because the new strain is resistant to the HIV medications the person is taking. (See resistance testing for an explanation of what it means for the virus to be resistant.)

For a person with HIV who is taking antiretroviral medicine and has an undetectable viral load, the risk of infecting someone else (or becoming re-infected) through sex is extremely low. If you have (or your partner has) a viral load that is not fully suppressed with HIV meds and a virus that has resistance mutations, it would be a good idea to use condoms to prevent transmission of a difficult-to-treat HIV infection.

There are more reasons for two HIV-positive people to use condoms. Correct condom use can prevent the transmission of other STDs, such as gonorrhea, chlamydia, syphilis, hepatitis B, and hepatitis C. And, condom use can prevent unintended pregnancy.