Scientists know it as ALVAC-AIDSVAX. You know it as the HIV vaccine that a Thailand study found could help reduce the risk of contracting the virus by a third — the one that everyone was sooooo thrilled about yesterday. But maybe it’s not such a big deal after all?
“The results were barely significant on statistical grounds,” relays the Washington Post. Wait. How could that be? If they were so insignificant, why was the HIV/AIDS community popping the bubbly?
In the study, volunteers in two provinces in central Thailand were randomly assigned to get vaccine or placebo shots. About 40 percent were women, and many were employed in manufacturing and shipping enterprises along Thailand’s coast. They were counseled on ways to avoid HIV infection and advised to use condoms.
There were few intravenous drug users and male homosexuals — groups at unusually high risk for HIV that make up most of the infected population in North America and Europe. In Africa and much of Asia, heterosexual intercourse is the most common route of infection.
Of 8,197 people who got vaccine, 51 became infected in the three years after their shots. Of the 8,198 who got placebo injections, 74 became infected. While that difference — 23 infections out of more than 16,000 people studied — is significant, it could have occurred by chance.
The results have at least one part of the AIDS research community doubting the vaccine as as significant development (though they don’t want their names in such a report, which makes sense).
On the other hand, even a modestly successful means of prevention is reason to celebrate, because it shows a vaccine is possible. In theory.
How about we take this to the next level?
Our newsletter is like a refreshing cocktail (or mocktail) of LGBTQ+ entertainment and pop culture, served up with a side of eye-candy.
And then there’s this possibility: The (immediate) future of fighting HIV/AIDS lies not in a vaccine, but in PrEp drugs.
A Spoon Full Of Sugar
These were the same type of results researchers got with circumcison studies, yet circs are being touted as the savior of African nations, while this vacine is being downplayed.
tavdy79
Even if it does work (we’ll have to wait for the results of the studies first) PrEP won’t impress me much – condoms protect against more than just HIV; PrEP will only protect against HIV.
Also, PrEP is only really feasible for those who have the money to buy the drugs or live in countries with universal healthcare systems. The leaves hundred of thousands in America, and tens of millions in Africa, unable to use PrEP. In Africa and other poorer areas of the world this would be a good thing – Condoms provide more complete protection because they protect against STDs other than HIV. But in wealthy countries that don’t have universal healthcare, like the USA, PrEP could actually become a problem if it becomes seen as the predominant form of preventing HIV infection. Using condoms would become a symbol of poverty – only those who cannot afford PrEP would use them, after all – and some may choose to risk unprotected sex rather than admit that they’re poor.
A key difference between PrEP and condoms is that if you’re using a condom to protect against HIV there’s no faking it. It’s easy to lie about whether or not you’re taking a drug; it’s not so easy to lie about whether or not you’re using a rubber.
B
“Of 8,197 people who got vaccine, 51 became infected in the three years after their shots. Of the 8,198 who got placebo injections, 74 became infected. While that difference — 23 infections out of more than 16,000 people studied — is significant, it could have occurred by chance.”
The probability that the vaccine did nothing is between 2 and 3
percent. That’s why people are excited – we have a candidate for a vaccine that is worth larger scale testing.
Initial tests typically use small sample sizes because to half the error, you have to quadruple the number of people in the study. It’s better to do a lot of smaller studies to find which ones are likely to work and then check those in detail.