Q and A

Question

Can I have sex with someone who is positive and not catch HIV?

Answer

Yes, there are lots of ways to make sure HIV is not transmitted during sex.

  1. One of the easiest and most effective ways is just for the HIV positive partner to be on treatment. An undetectable viral load makes HIV untransmittable. (See: The evidence for U=U).
  2. Another relatively recent option is for the negative partner to use PrEP. This is an oral drug that when taken as prescribed is highly effective. (See: UK guide to PrEP).
  3. You can use condoms which are an effective barrier against HIV (and other STIs). Condoms need to be used carefully, preferably with plenty of lube. (See: How to use a condom (male and female).

HIV is a much less infectious virus than many other sexually transmitted infections (STI’s).

Even without a condom, the risk from a single exposure is less than, for example, 1 in 300. The actual risk becoming infected varies depending on many factors. These include the type of exposure, whether the other person is HIV positive, how high or low their viral load is, the duration and roughness of the sex etc.

If the partner is HIV positive, then viral load is the most important factor. The PARTNER study reported zero HIV transmissions after 900 couples had sex more than 58,000 times WITHOUT condoms. In this study undetectable viral load was defined as being less than 200 copies/mL.
https://i-base.info/qa-on-the-partner-study

Risk factors for penetrative sex without a condom with someone who has a very high viral load could be as high as 1 in 10 (10% risk). But the risk is effectively zero with someone who is taking treatment and who has an undetectable viral load.

This question was updated in January 2018 and November 2016 from an original answer posted in June 2007. i-Base no longer answers individual questions about HIV transmission and risk. (See: Question 1 at this link).

209 comments

  1. Lisa Thorley

    Hi Xoli,

    Yes this is correct. You can’t transmit.

  2. Xoli

    Thank you, Lisa, for the response.

    So if the male is positive but on effective treatment with a viral load of undetectable levels; there is no need for the female partner to take any medication as there is a close to Zero chance of infection? Considering that the female is negative?

  3. Lisa Thorley

    Hi Xoli,

    Babies can only be positive if their mothers are positive and this is something that can be reduced by medication.

  4. Xoli

    Good day.

    I would like to know this: If I (male) am HIV+ with an undetectable viral load have sexual intercourse with a female who’s HIV- and she falls pregnant. Will it mean that the baby that she will be carrying will be HIV+?

  5. Lisa Thorley

    Hi Portia,

    Please see Q’s 1 and 9 here:

    http://i-base.info/qa/what-are-the-most-asked-questions

  6. Portia

    I slept with someone who is positive 4 times. How easy it is to contract HIV?

  7. Lisa Thorley

    Hi Luisa,

    Please see Q’s 1 and 9 here:

    http://i-base.info/qa/what-are-the-most-asked-questions

  8. Luisa

    Hi, I had anal protected sex (condom) with an HIV+, he came outside of me because he was taking so Long and I got tired, accidentally his semen jumped Into my arm; at the time we got sex I Didnt know his status, I found out that he was positive because he asked to do it without condom so I said ill do it if he got tested, we went to a lab about 5 weeks after sex (may 25) I got negative and he was positive, we never had sex again, in fact I havent had sex since then (April 19) I retested on June 01 because Im all freaked out, my question is: can I still become positive from that sex exposure?

  9. Lisa Thorley