Your and your partners HIV status

When both partners are negative

HIV has to be present for any risk of transmission. If both partners are HIV negative, then transmission cannot occur.

This involves knowing you and your partners current HIV status. This is not the same as knowing their status last year, or the last time either of you tested. Two partners having sex without a condom need to trust that neither partner could catch HIV outside the relationship.

Not all monogamous relationships are monogamous all of the time.

When relationships change or breakdown this often involves other sexual partners.

Sometimes it might be easier to continue using condoms that raising these issues of trust.

HIV negative people do not need to use condoms with each other if they:

  • Are both HIV negative (confirmed test and no risks since).
  • Have had no risks in the three months before their last HIV test and no risks afterwards.
  • Are not concerned about pregnancy.
  • Are not concerned about STIs.

If you don’t know you or your partners HIV status

If you are negative and don’t know your partners status, it is always better to assume they are positive.

If you don’t know your HIV status, assume you are positive (in terms of not putting anyone at risk yourself).

If you do this – rather than assuming your partners are negative – you will not take risks that you are not happy with.

You will feel in control during sex and you will not feel anxious or worried afterwards.

Your HIV status is only as accurate as your last test result, plus the risks you have taken since.

Risk of catching NEJMIf one partner is positive and one is negative

If one of you is HIV positive and one of you is HIV negative, you need to be careful to reduce the risk of transmission.

This involves learning about which activities have a risk and which are most safe.

If the HIV positive person has an undetectable viral load on treatment then the risk of transmitting HIV is close to zero – even without a condom.

If the HIV negative person is taking PrEP then the risk of transmission is also close to zero – even without using a condom.

PrEP is when HIV drugs are taken by an HIV negative person before and after sex to reduce the chance of infection.

Condoms, if used correctly, protect against HIV, so most sero-different couples become very good at using condoms.

There are lots of couples where HIV status is different. You can have a full and active sex life without the negative partner ever catching HIV.

See the sections in this guide on viral load, on condoms and on PrEP.

When both partners are positive: what about reinfection?

Many HIV positive people have sexual partners who are also HIV positive.

If both partners are positive this removes the anxiety of worrying about HIV, even when risks are low.

There are not a great number of benefits from being HIV positive, but for many people, this is one of them.

Knowing about reinfection is important. If either partner has drug resistance or a different type of resistance this can be transmitted.

How often reinfection occurs is not known. The risk is probably at least as low as catching HIV the first time. This will be higher if viral load is detectable and dramatically less for someone on effective treatment.

The implications for your health if reinfection occurs will depend on how serious the resistance is.

We mainly know about reinfection because of cases where the new infection has caused treatment to fail.

This means knowing about both your and your partners treatment history.

If neither of you have resistance, or if you both have the same resistance, then there is unlikely to be a problem from not using condoms (other than STIs or pregnancy).

But if one of you has resistance, especially with a detectable viral load, then reinfection would stop the chance to use these drugs.

Last updated: 1 June 2016.