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The ABCDs of prevention
HIV prevention is as easy as ABCD
- A for abstain - abstain from casual sex
- B for Be faithful
- C for condom usage
- D for detect early.
Some other methods to prevent HIV if you are HIV negative is avoid sharing of needles for injection using pre-exposure prophylaxis medications if engaged in high risk sexual activities
How to prevent spreading to others?
How do you prevent yourself from spreading HIV to others if you are positive?
- Abstinence from sex is the best method but we know its not easy
- getting yourself treated and managed properly so that your viral load is very low or undetectable
- only having sex with partners of the same HIV status
- again, using condom
Concept of u=u
Here we will share this concept of undetectable equals untransmittable or u=u for short. This is a key concept that is vital in the prevention of HIV transmission and in allowing HIV positive patients to have a fulfilling sexual relationship with a partner who is HIV negative.
What is HIV viral load?
HIV viral load refers to the amount of virus within your bloodstream. In general, the higher the viral load, the more infectious you are.
Someone with HIV that is untreated, may have thousands, even millions of HIV virus per millilitre of their blood. However, when this same patient is started on Anti-retroviral therapy, the viral load may drop to undetectable levels within 6 months.
The importance of undetectable HIV load
“Partner 1” Study
The result of the “ Partner 1 “ study was announced in 2016 where 88 couples were recruited in this study. 38% of them were gay male couples, the rest heterosexual.
Amongst these couples, one had to be HIV positive and the other had to be HIV negative.
The HIV positive individual must be well treated with a viral load that is less than 200 per millilitre of blood. Amongst these 888 couples, there were an estimated 58,213 sex acts, all of which were condomless. Amazingly, there were zero HIV transmissions amongst them.
“Partner 2” Study
The scientific world felt that a study that focused on gay men would be necessary as rate of transmission of HIV in anal sex was higher than vaginal sex. As such, in 2018, the result of the “Partner 2 “ study was released. In this study, 635 Gay men only couples were recruited, of which one partner was HIV positive and the other negative.
Again, the HIV positive individual had to have a viral load of less than 200 per millilitre. Amongst them, an estimated 77,000 condomless sex were estimated.
The result? Zero HIV transmissions.
“Opposites attract” Study
In 2017, a similar study of 343 gay male couples called “ Opposites Attract “ also found no hiv transmissions from partners with an undetectable viral load in 17,000 acts of condomless anal sex.
Between these three studies, no transmission of HIV from a hiv positive sexual partner with an undetectable viral load was seen in nearly 130,000 acts of condomless penetrative sex.
These findings have been life changing for many people living with HIV. It means that if you are on effective treatment with an undetectable viral load, you do not have to worry about passing on HIV through sex, even if you do not use a condom.
Therefore if you are a HIV positive patient, please get yourself treated and followed-up to ensure that your viral load is in the undetectable range. This is the best way of protecting your loved one from catching it.
HIV prevention
There are also medications to prevent HIV. They include :
- Pre-exposure prophylaxis ( PrEP )
- Post exposure prophylaxis ( PEP )
Prep or pre exposure prophylaxis
These are medications that you take to reduce your chance of getting HIV from sexual interaction and drug injections. Examples include Truvada and Descovy.
If taken in the correct manner, PrEP reduced the risk of getting HIV from sex by about 99%, This also reduced the risk of getting HIV from sharing of needles by at least 74%. However the effectiveness drops if its not taken in the prescribed manner.
Side effects of PrEP includes diarrhoea , abdominal pain, nausea, headache and fatigue.
So How long do you have to take PrEP before it becomes effective?
- For receptive anal sex - about 7 days
- For receptive vaginal sex and injection drug use - about 21 days
- No data are available for insertive anal or insertive vaginal sex yet.
You are not suitable for PrEP if
- you already have HIV
- there is clinical suspicion that you may have HIV
- your kidney is not functioning normally
- or you are allergic to the medication
Who may be suitable?
- If you are a sexual partner of someone with HIV but not on treatment
- If you have multiple sexual partners within last 6 months without the use of condom
- If you have been diagnosed with STD in the past 6 months
- Received HIV post-exposure prophylaxis in the last 6 months
- If you engage in sexual activities under the influence of alcohol or other drugs
Please speak to your doctor to find out more about taking PrEP and the required follow up.
PEP or Post exposure prophylaxis
These are emergency drugs that you take after a possible HIV exposure. They must be started within 72 hours of the exposure. Some emergency situations could be like needle prick injuries to health care workers, or when the condom breaks during sex or after you’ve been sexually assaulted.
The sooner you start the PEP, the better. Once you’ve been started on PEP, you need to continue to take it daily for 28 days.
PEP is not the right choice for people who may be exposed to HIV frequently such as commercial sexual workers or promiscuous individuals. It should not also be used as a substitute for other HIV prevention methods like condom.
By : Dr Chen Yiming
Family Physician, MBBS (Singapore), GDFM (NUS), GDFP Dermatology (NUS)