Treatment as Prevention

What is TasP?

What’s known as Treatment as Prevention (TasP) is when HIV-positive individuals go onto HIV treatment to reduce the possibility of transmitting the virus onto someone else, or in other words using treatment as a way to prevent the transmission of HIV by reducing a person’s infectiousness.

Sero-discordant relationships

Opposites Attract

A serodiscordant relationship is one in which one partner is HIV-negative and the other is HIV-positive. All couples face conflict and obstacles, but emotions can become even more complicated when you share your life with someone who has a different HIV status than you. The conflicting emotions and feelings can sometimes be overwhelming and can leave either partner in a vulnerable position.

It Takes Two

It is important to realise that both the HIV-negative and HIV-positive partner in the relationship will each have some concerns at the beginning and throughout the relationship.

Things the HIV-positive partner may be concerned about include:
  • Rejection or abandonment;
  • Transmitting HIV to their partner;
  • Health issues and illness;
  • Effects of treatment and energy levels;
  • Planning for the future;
  • Disclosure and privacy issues in talking to others about the relationship and their HIV status.
Things the HIV-negative partner may be concerned about include:
  • Guilt that his partner is HIV-positive and he isn't;
  • Feeling that if he had HIV too he'd feel closer to his partner;
  • Fear of becoming HIV-positive from their partner;
  • Fear of losing their partner to health issues and illness;
  • Stigma and disclosure to friends and family about being in a serodiscordant relationship:
  • Issues around getting tested, and how often they should be tested.

What's important to understand is that while each partner may have their own concerns, there will probably be some common themes among them. Open and honest communication is the key to being able to come to a common ground, and being able to support one another during the relationship – good times and bad.

Keep on Talking

Talking about your feelings with each other is a practical way of working through some of the complex issues that are raised in a serodiscordant relationship. Not discussing these issues can lead to risky behaviour, greater anxiety and trouble in the future of the relationship.

Here are some key points of discussion that can be considered:

Emotional health

Discuss your fears and explore any feelings or issues that your other partner may be experiencing of thinking about. Identify areas where you need each other's support, or perhaps the support of a professional.

Sex and transmission

Discuss each other's concerns about transmission from one partner to the other. Come together with a safe plan that includes what precautions each of you will take, what risks you are willing to take, and what activities you feel comfortable getting up to. Other elements to consider and become informed about that may reduce concerns regarding transmission include PrEP (Pre-Exposure Prophylaxis) and what it means to have an undetectable viral load. It can also help some couples to discuss an emergency plan including knowing how to access PEP (Post-Exposure Prophylaxis) should an accidental unintended exposure incident occur. It is also worth having a discussion around how both partners feel about condom use and how that factors into what risk reduction strategies you both decide to utilise.

Negotiating sex - communication strategies:

  • Listen to each other, both of you should have a say in what you are going to engage in - if either person does not want to engage in an activity, that person has the final say;
  • Get educated together about what can make your sex practices safer if you're not sure about what activities are safe, and which can be risky;
  • Know that HIV transmission isn't the only risk; be aware of the risk of other sexually transmitted infections;
  • Communicate your fears – talk about your concerns;
  • It doesn't all have to be about anal sex – talk about alternatives for sex play.


Be open and honest about your concerns with things like treatment side effects, difficulties adhering to the daily treatment regime, and its potential impact on both your physical and mental health. For more information about treatments and the important factors relevant to HIV treatment check out


Talk about some of the issues regarding disclosing of each others’ HIV status outside of the relationship. While not disclosing may reduce the effects of stigma and discrimination, disclosing may increase support and reduce isolation. Keep in mind that the effects of disclosure may have more of an impact on the HIV-positive partner, and as such, it is crucial that it is a joint decision and that he has a big say in how that information is divulged and to whom.

It's important to remember that just like with any other relationship, all parties need to respect each other's decisions. You may find it helpful to seek professional support for the issues that you and your partner have the most difficulty with.

Undetectable viral load

There is some uncertainty amongst men when it comes to fucking without condoms with someone whose status is different to theirs and the associated risk of contracting and/or transmitting HIV, especially if the HIV-positive partner has a low or undetectable viral load level. This section explains what viral load means and what the concept of an undetectable viral load (UVL) means in relation to HIV risk.

What is viral load?

Viral load refers to the amount of HIV circulating in the blood. To find out a person’s viral load, a doctor takes a sample of blood and sends it to a laboratory where a viral load test is conducted.

When the result comes back, viral load is indicated as a number. The number indicates the amount of viral copies per millilitre of blood (written as copies/ml). Viral load can range from below 20 to over one million copies/ml. In layman’s terms, viral load refers to the amount of virus that is in the HIV-positive persons’ body.

What does undetectable mean?

An undetectable viral load level is when the level of the virus in the body is reduced to a point that it cannot be detected by current tests. This does not mean that their body is free or cured of HIV, only that there is less than the test can detect.

In fact, all HIV positive people with an undetectable viral load still have HIV in their blood, as well as in blood cells, tissue and other bodily fluids. HIV-positive people on sustained anti-HIV treatment regimes are commonly able to maintain their viral load at low or undetectable levels.

Viral load and fucking without condoms

The current research has indicated that if the HIV-positive partner has a sustained undetectable viral load level and is on effective treatment their ability to transmit HIV to the negative partner is basically eliminated during sex without condoms.

The PARTNERS Study, looked at over 22,000 cases of condomless anal sex between gay couples where one person was HIV-positive and had an UVL, and the other person was HIV-negative. They found that there were no cases of HIV transmission. This is just one of many studies regarding viral load and HIV prevention.

The body of evidence indicates that using an undetectable viral load level as a strategy is an effective way to prevent HIV transmission.

Viral load issues

There is one factor that can make undetectable viral load ineffective in preventing HIV transmission, and that is when the HIV-positive persons’ viral load changes rapidly as a result of their anti-HIV drugs not working effectively. This rarely happens with someone who is on an effective and sustained treatment regimen, but if you have HIV and you are on antiviral treatment it is important to have your viral load level checked regularly to ensure that it remains undetectable.

Viral load reduction

Whilst the majority of positive people on treatments will be able to reach an UVL, there is a smaller proportion that for a variety of reasons are unable to do so. These can include a problem with taking the drugs as prescribed, having to try several different combinations of drugs over a longer period of time, or due to medical reasons, such as the intolerable side effects.

It is important to note that treatments do not automatically guarantee that people will achieve an UVL. However, taking treatments means taking control of your health. Virtually everyone who is on treatment has a significantly reduced viral load, giving them the best chance of maintaining their health and reducing the risk of transmission.

Viral load and STIs

It’s important to understand that having an undetectable viral load will not protect you against other STIs and if you and your partner(s) intend on using this strategy to protect yourself against HIV then you should be having regular sexual health check-ups and keeping condoms in the mix as they remain the best way to prevent most STIs.