There has been a rapid, historic shift in HIV prevention among gay and bisexual men in Australia, according to a new analysis of community surveys over five years. While consistent condom use has fallen dramatically, the uptake of PrEP and HIV treatment mean that “net prevention coverage” has increased. The study by Professor Martin Holt of the University of New South Wales is published in the April issue of AIDS.
Australia has been a world leader in the rapid roll-out of the HIV prevention medication PrEP among gay and bisexual men. HIV treatment is available free of charge for most people and the benefits of HIV treatment for prevention have been promoted.
Data for the study come from 32,048 responses to the Australian Gay Community Periodic Surveys, conducted between 2014 and 2019. Participants are recruited at gay venues, gay events and online. This analysis only included men who reported casual sex.
Half the participants were aged between 27 and 45 years. Most identified as gay (90%) or bisexual (7%) and were born in Australia (70%). Their self-reported HIV status was negative (82%), positive (10%) and untested/unknown (9%). One third lived in New South Wales, one third in Victoria, one fifth in Queensland, and the rest elsewhere in Australia.
The repeated surveys over the five-year period allow comparisons over time. Asked about sex with casual male partners in the past six months:
- Not having anal sex with casual partners was reported by 18% in 2014 and 15% in 2019.
- Consistent condom use was reported by 45% in 2014, falling to 23% in 2019.
- PrEP use by men who had condomless sex was reported by 0.7% in 2014, rising to 31% in 2019.
- Taking HIV treatment and having an undetectable viral load, and also having condomless sex, was reported by 4.8% in 2014 and 5.8% in 2019.
- Condomless sex, reported by a man who was HIV negative or untested and not on PrEP, was reported by 30% in 2014, falling to 25% in 2019.
- Condomless sex, reported by an HIV-positive man who was not undetectable, was reported by 1.6% in 2014, falling to 0.6% in 2019.
Whereas the last two groups have a risk of being involved in HIV transmission, the first four are covered by HIV prevention. Summing the numbers in the first four groups, net prevention coverage increased from 68% to 75% over the five-year period.
The researchers note that their estimate of prevention coverage is conservative. It does not take into account information about men’s partners. For example, an HIV-negative man who is not on PrEP and has condomless sex is put into a risky group even if he did so because he knew his HIV-positive partner was undetectable.
In fact, looking at the HIV-negative men who were not on PrEP and had condomless sex, by 2019, 34% of this group said they often had casual sex with men who were on PrEP and 15% said they often did so with men who had an undetectable viral load.
“Our analysis of national behavioural surveillance data demonstrates a historic change in the sexual practices of Australian gay and bisexual men,” conclude Holt and colleagues. “Between 2014 and 2019, the most commonly used HIV prevention strategy by gay and bisexual men with casual partners changed from condom use to PrEP.”
These shifts are likely to have contributed to recent declines in HIV infections in Australia, they add.
Holt M et al. Increasing preexposure prophylaxis use and ‘net prevention coverage’ in behavioural surveillance of Australian gay and bisexual men. AIDS, 35: 835-840, April 2021.