How does someone get HIV?

The HIV virus is found in semen, blood, rectal fluids, vaginal fluids and breast milk.

HIV is transmitted:

  • through having sex without a condom (vaginal, anal) with someone who is HIV positive and not on effective HIV treatment*
  • vary rarely through oral sex without a condom with someone who is HIV positive and not on effective HIV treatment* (this risk is extremely low)
  • through sharing needles or injecting equipment with someone who is HIV positive and not on effective HIV treatment*
  • during pregnancy, delivery or breastfeeding from mother to child where the mother is not on effective HIV treatment*
  • through contaminated blood products (very unlikely in Ireland as all blood donations are tested

HIV infection can be hard to spot in its early stages. Left untreated, a person with HIV will become very unwell over time.

You cannot get HIV:

  • From sharing food, cooking or eating utensils
  • From kissing
  • From shaking hands or hugging
  • From the toilet or swimming pools
  • From spitting or biting
  • From sneezing

It is extremely unlikely that you will get HIV from oral sex although there is a theoretical risk if you have open sores in your mouth.

Being Undetectable (U=U)

Viral load is the term used to describe the amount of HIV in the body at any one time. It is determined with a blood test.

A higher viral load is associated with a higher risk of HIV transmission. With successful HIV treatment, the viral load can become so low that it is considered ‘undetectable’ in the blood, and this reduces the risk of HIV transmission to zero.

*Effective HIV treatment

When a person living with HIV is on treatment and the level of virus (viral load) in the body is so low that it cannot be detected (is ‘undetectable’), HIV cannot be transmitted to sexual partners. This is also known as ‘undetectable’ equals ‘untransmittable’ (U=U).

A lot of people with HIV see becoming undetectable as a very important benefit of HIV treatment, which decreases anxiety about onward transmission to a sexual partner. People are now taking their viral load into consideration when thinking about safer sex.

If you want to stop using condoms, it is important to discuss this carefully with your partner(s) and ensure they are also comfortable with the decision. This information may be new to a lot of people who do not have HIV; it may take time for someone to understand and trust what you are saying. It is also important to remember that while using this approach will protect your partner(s) from HIV, it does not protect them or you from other STIs.

The following are some guidelines for men who may be thinking about using this approach to reduce the risk of HIV transmission:

  • the viral load can increase if doses of HIV treatment are missed. Take pills exactly as prescribed. Adherence to treatment is critical to keep the viral load undetectable;
  • check to make sure the blood viral load is undetectable before starting this approach, and get regular viral load tests to ensure it remains undetectable.
  • as a guideline, it is suggested that you and your partner(s) wait until your viral load has been undetectable for at least six months before making any decisions about whether to stop using condoms;
  • get tested regularly for STIs. If either partner has an STI, start treatment immediately and consider using condoms during this time as viral load may spike;
  • if you have not already done so, get vaccinations for hepatitis A and B;
  • use other HIV prevention strategies as much as possible. This will help reduce the overall risk of HIV transmission.

If you use this approach without disclosing your HIV status, it is important to remember that in some countries, having sex without condoms without disclosing that you are HIV positive is a criminal offence, regardless of the likelihood of HIV transmission.

HIV transmission and the Law

Travel, mobility and migration are increasingly part of our lives.

It’s important to be aware that in a number of countries, criminal law is being applied to people living with HIV who transmit or expose others to HIV infection. Different countries have different laws.

Currently, criminal prosecution for the sexual transmission of HIV remains untested in Ireland, in both the Republic and Northern Ireland.

The following is an example of how the law has been applied in England and Wales.

This is not legal advice. It is an example that you may wish to consider when making your choices about disclosure.

In England and Wales, people living with HIV may be prosecuted with ‘reckless HIV transmission’ under section 20 of the Offences Against the Person Act 1861. It’s worth noting that this guidance applies to England and Wales only, although the Offences Against the Person Act still applies in Northern Ireland.

In the UK, based on the criminal prosecutions to date, a person may be prosecuted for reckless transmission of HIV if:

  • the person knows he/she is HIV positive.
  • the person understands the risk of HIV transmission.
  • the person engages in risk taking sexual behaviour, and as a result the person infects his/her sexual partner.
  • the person has not previously disclosed his/her HIV status to that sexual partner.

Although UK law does not precisely define ‘safer sex’, from the cases brought to court so far in the UK, it seems that a person will not be prosecuted if condoms are used for anal sex – as long as they have been used 100% of the time.

The law in the UK is not explicit in relation to a situation where a condom splits or slips off. The advice given in the UK is to disclose HIV status immediately and advise your sexual partner to get PEP.

The UK law covers any serious infection that is passed on sexually, so a prosecution for the transmission of Hepatitis C is also possible.

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