HIV prevention pill myths busted
A single pill could slash your risk of HIV infection — could it be for you?
More people than ever are taking the oncea-day pill to prevent HIV infection. As of the beginning of this month, HIV-negative men who have sex with men in Tshwane are the latest to get access to Truvada, a two-in-one antiretroviral.
When the pill is taken daily as pre-exposure prophylaxis (PrEP), it can reduce a person’s risk of HIV infection by between 44% and more than 90%, depending on how well it’s taken, studies have shown.
In March 2016, the health department began providing PrEP to up to 5 000 sex workers. Men who have sex with men are expected to be next on the list of people getting access to the drug nationally in the public sector.
Meanwhile, anyone who thinks they are at a high risk of contracting HIV can approach their private GP for a prescription, so could the HIV prevention pill be right for you?
Speaking at a recent forum, Anova Health Institute senior clinical specialist Kevin Rebe debunked some of the myths that could be standing between you and PrEP.
Myth: Taking PrEP will increase my risk of developing antiretroviral (ARV) resistance
Truvada can be used to prevent HIV infection. But when used in combination with other ARVs, the two-inone pill can also be used to treat HIV.
People living with HIV must take a combination of three antiretrovirals to prevent the virus from replicating and stay healthy. Just as with other conditions, if HIV-positive people skip doses — or take only one or two of the three medicines — they risk developing resistance to the drugs.
This has led to fears that people who take Truvada as PrEP could become HIV positive but not know it, meaning they would only be taking two out of the three drugs needed to control the virus, which could lead to resistance.
But Rebe says there is no evidence that taking PrEP fuels ARV resistance. Two large studies found few instances in which people acquired resistance while taking the pill.
A 2010 study conducted among almost 2 500 men who have sex with men found that only two men developed ARV resistance. Published in The New England Journal of Medicine, the research found that this pair had been newly infected with HIV when they began taking PrEP. This means they were in a short window period during which they had already contracted the virus but may not have tested positive for HIV with conventional testing.
Rebe says the number of HIV cases that can be prevented through PrEP far outweighs the small percentage that may face ARV resistance.
South African PrEP guidelines require those taking the tablet to undergo HIV testing every three months. People who test positive should stop taking Truvada immediately and switch to the three-in-one combination ARV most frequently used to treat HIV in South Africa.
Myth: PrEP will increase my risk of contracting a sexually transmitted infection
No clinical trial or pilot programme has shown that PrEP use leads to an increase in sexually transmitted infections (STIs), says Rebe.
On the contrary, he expects that PrEP will be revolutionary in bringing down STI rates as users are required to go for health checks every three months.
Myth: People taking PrEP are more promiscuous
Some people fear PrEP users will engage in risky sexual behaviour because they believe they are completely protected from HIV.
Rebe says there is no evidence to back this claim. Instead, he says clinical trials found that users had safer sex. This may be owing to the mandatory quarterly counselling sessions PrEP users receive.
The 2010 research published in The New England Journal of Medicine found no evidence that PrEP users took more risks. Follow-up research in 2014 conducted as part of the same study found that people on the HIV prevention pill had less unprotected sex and fewer STIs over time.
Rebe says this trend proves the efficacy of the safer-sex counselling that goes along with PrEP. Although PrEP may draw more risk takers it won’t turn you into one.
“PrEP does not change your personality, it will not make you more ‘out there’. But it might bring the most risky people into your [health facility],” says Rebe.
Myth: I can’t take PrEP because I’m pregnant
There is insufficient long-term research on the effects of PrEP on pregnant women and their babies, and concerns about this have kept HIV-negative women out of PrEP clinical trials. But some pilot projects are evaluating it.
Meanwhile, there is no evidence of harm to babies who were born to women living with HIV when they took Truvada as part of HIV treatment, notes the United States Centres for Disease Control and Prevention on its website.
But PrEP could be key to decreasing HIV infection rates in pregnant women.
A 2015 study published in the PLoS ONE journal estimated that about 3% of women who initially test HIV negative during their pregnancy will contract HIV before giving birth. This is an infection rate a lmost twice that among women in general.
As of May 2016, the World Health Organisation was still reviewing research on the safety of Truvada use in pregnant women.
But national guidelines say those who are pregnant and at high risk of contracting HIV should make an informed decision about taking the HIV prevention pill after speaking with their doctor.