Q and A

Question

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

16 January 2018. Related: All topics, HIV transmission.

Answer

Answer: Simon Collins

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. Nomveliso •

    Hi
    I am Nomveliso. I slept with a person last year December 2016 who didn’t know if he was positive or not. I’ve since broke up with him because of distance. I’ve now heard some roamers that say he is ill and does not want to go for testing, should I worry?

  2. Lisa Thorley •

    Hi Bryan,

    Please see question 1 here:

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

  3. Bryan •

    I’ve had sex with a woman/ one night stand..First time I’ve ever done it.. I’ve asked her multiple times if she was OK or not, she said yes. We do it and I’m in her for no longer than 30 seconds.. I realize what I’m doing is bad and risky and stop..

    Few days later I have diarheeia , and now 2 weeks later I have a sore throats and slight fever.. I know this may be anxiety but freaking out in all the other possibilities.. btw where I’m at now everyone is sick (flu weather l/season) so I’m hoping what I’m experiencing is anxiety/ common cold due to weather..

    How safe am I? Considering I wasn’t in her for long.. (30 seconds max) I didn’t even come for crying out loud.. help guys..

    Question.. am I

  4. Lisa Thorley •

    Hi Juan,

    You can’t contract HIV from kissing. If you’re using condoms correctly there’s no risk. Furthermore, if your partner is on medication and has an undetectable viral load, the risk of transmission is close to zero. This is when having sex without a condom. Please see the results of the PARTNER study for more info:

    http://i-base.info/qa-on-the-partner-study/

  5. juan •

    I HAVE A PARTNER WITH HIV AND HAVE HAD PROTECTED SEX. WHAT ARE THE CHANCES I CAN GET INFECTED. WE DONT HAVE ORAL SEX, BUT WE DO KISS.

  6. Lisa Thorley •

    Hi Biggy,

    Please see Q1 here:

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

  7. biggy •

    i had sex with a girl and after the act i pulled out of her and discovered that the condom had broken, i took her for an HIV test in the morning and her test was NEGATIVE, what are my chances if she was in her window period, am i safe

  8. Lisa Thorley •

    Hi Smith,

    If you used a condom correctly you can’t contract HIV. For more info, please see Q1 here:

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

  9. smith •

    I had sex with a HIV positive girl but it was protected sex for both oral and vagina. Starting the next day, I have been having high body temperature especially at night…. Please help.

  10. Lisa Thorley •

    Hi Paven,

    For how HIV is transmitted, please see Q1 here:

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