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When you're both HIV positive


Relationships where both partners are HIV positive are sometimes called ‘seroconcordant’.

Some people with HIV prefer to have relationships with other HIV positive people. It might seem simpler and feel more comfortable when a partner knows what it’s like to have HIV.

However there's no reason to be put off having a relationship with someone who is HIV negative - if you're on treatment and have an undetectable viral load you cannot pass on HIV.

It can take up to six months for your viral load to become undetectable - so effective treatment means that someone has been taking it as prescribed for at least six months and has an undetectable viral load.

Is re-infection something to be worried about?

Re-infection is when:

  • you’re HIV positive,
  • you have unprotected sex with another person with HIV
  • one or both of you has a detectable viral load
  • and pick up (or pass on) a different strain of the virus.

This can be a problem if one person’s strain is resistant to particular antiretrovirals.

This used to be more of an issue when we understood less about the link between viral load and infectiousness. We now know that if you’re taking HIV medication and have an undetectable viral load you can’t pass on HIV.

HIV medication and infectiousness

In the UK, national guidelines currently recommend that anyone with HIV who is ready to commit to treatment should start it regardless of their CD4 count.

This means more people will be on treatment sooner and will have an undetectable viral load. This means they cannot pass on HIV - so although reinfection is a theoretical risk, it’s unlikely.

If you had drug resistant HIV your viral load would be more likely to be detectable, which you would be aware of, meaning you could use protection to avoid the risk of re-infection. If you have an undetectable viral load, this means you aren’t resistant to your medication.

If you have a detectable viral load or don’t know whether the person you’re having sex with is undetectable, using a condom will prevent the theoretical risk of re-infection.

Other risks

Another issue to consider is that if you have sex without a condom there is a chance you’ll pick up a sexually transmitted infection (STI).

STIs such as herpes, syphilis, gonorrhoea, chlamydia and hepatitis C can interfere with your HIV treatment and make you more ill.

Sex without a condom can also result in an unplanned pregnancy if other contraception is not being used.

Monogamy and open relationships

You and your partner should talk to each other and agree whether your relationship will be monogamous (no sex outside the relationship) or ‘open’ (sex with others allowed).

There are risks in not discussing it and assuming that your partner agrees with you. Some people who think they’re in a monogamous relationship find out that their partner has had sex with others.

Both monogamous and open relationships can bring benefits and challenges. For example, some couples in monogamous relationships say they enjoy feeling both physically and emotionally committed to only one person. However, they may feel frustrated if they have a higher or lower sex drive than their partner.

Some couples in open relationships say they enjoy the sense of freedom and variety it can bring, but it can also highlight any feelings of jealousy or insecurity within the relationship. Mutual trust and honest communication are vital in both monogamous and open relationships.

If you both agree to be monogamous it’s important to discuss what would happen if either of you broke this agreement. If either of you feel that you must hide the fact that you’ve had sex outside the relationship, that can seriously threaten your relationship.

One advantage of monogamy is that no STIs are likely to come into your relationship.

Using condoms with people outside your relationship will make it less likely that you’ll pick up infections (and give them to your partner) although some STIs can be passed on despite using condoms and through oral sex.

If you’re planning to have sex with HIV negative partners you could pass on HIV if you do not have an undetectable viral load.

Quote reading:

More information for couples affected by HIV:



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  • The most important thing is to realise that it is not end of the world.

    Posted 18:30 Thu 12 Sep 2013
  • Good morning
    My self ami m HIV positive boy
    my question is
    What effect in my body if I get marry to HIV positive girl
    Is anything change in my blood or body or health ?because
    Right now my cd4 count 638 and viral load found undetected
    Physically m slim and well not having any other problem
    Let me know please

    Posted 10:58 Thu 07 May 2015

The Information Standard: Certified member

This article was last reviewed on 25/1/2017 by Anna Peters

Date due for the next review: 25/1/2020

Content Author: R. Scholey

Current Owner: Kerri Virani

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HIV treatment as prevention and HPTN 052, Cohen MS1, McCauley M, Gamble TR
National Center for Boiotechnology Information
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Is reinfection a risk if two HIV positive people are undetectable?, Simon Collins, HIV i-Base, September 2014

Viral load and transmission, a factsheet for people with HIV, Gus Cairns, NAM aidsmap, September 2015

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Redd A et al. Next-generation deep sequencing reveals that the rate of HIV superinfection is the same as HIV incidence in heterosexuals in Africa. 19th Conference on Retroviruses and Opportunistic Infections, Seattle, abstract 58, 2012.

Ronen K et al. Detection of frequent superinfection among Kenyan women using ultra-deep pyrosequencing. 19th Conference on Retroviruses and Opportunistic Infections, Seattle, abstract 59LB, 2012.


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Further information on the current risk of re-infection/superinfection taken from discussion with Dr Michael Brady.