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. Grant •

    I jus found out that the girl i live is HIV positive.. we’ve been together for 1 year 8months and we dont use any condom.. do i have a chance of being HIV negative? ?

  2. Simon Collins •

    Answers to questions on testing are already online at the FAQ page.
    http://i-base.info/qa/factsheets/hiv-transmission-and-testing

    or in this guide:
    http://i-base.info/guides/testing

  3. Arun •

    I think I had sex with HIV positive person, but I did use condom and now I’m super scarred I might have HIV/AIDS, what are the chances me getting infected? And c was going through her period. Can any one help me ?

  4. Roy Trevelion •

    Hi, If your partner was on HIV treatment (ART) and had an undetectable viral load the chances are close to zero.

    The recent PARTNER study showed that with an undetectable viral load, almost 900 sero-different couples had sex more than 58,000 times without using condoms – and without a single case of HIV transmission.

    And the results were not affected by other STIs.

  5. joseph •

    I slept with someone with HIV and catch an STI from her but I was diagnosed negative and we’ve been together for 3 years now. Are there chance of being infected with the virus?

  6. Roy Trevelion •

    Hi Martha, You don’t say if both you and your partner are HIV positive. And do you mean to ask about being infected?

    However, it is very common for someone to still be negative even if they have not been using condoms with someone who is HIV positive. HIV is quite a difficult virus to catch, so this is also related to risk and luck.

    You can find out more about this question here:
    http://i-base.info/qa/7308

  7. martha •

    If you’re HIV positive for 14 yrs and you slept with your partner 14 yrs it possible to be affected?

  8. Roy Trevelion •

    Hi Cletus, Thanks for this. The i-Base site is a great resource for this information.

    The i-Base guide to ART includes information about the most important aspects of HIV treatment. It is written and reviewed by HIV positive people and it uses everyday language to explain medical terms.

    You can find it here:
    http://i-base.info/guides/starting

  9. Cletus •

    I want more lessons about these things about HIV and AIDS because l want to help many young people in my area
    please help with all new information about this
    thank you

  10. Roy Trevelion •

    Most people take many years to develop symptoms that are related to HIV. These symptoms are the result of damage to your immune system. And this damage usually takes years to occur.

    If you are asking about symptoms that some people get in the first week or 10 days of infection then it’s called seroconversion.

    You can find out more about seroconversion on this previous Q&A:
    http://i-base.info/qa/284