Despite increasing HIV prevention among gay and bisexual men in Australia, some men less well protected

HIV prevention coverage is increasing among gay and bisexual men in Australia, but some men remain less well protected. Gay and bisexual men under the age of 25, bisexual men of all ages, and men living in suburbs with fewer gay residents have higher levels of HIV risk and lower levels of prevention coverage.

The addition of PrEP and viral suppression to the arsenal of HIV prevention strategies has decreased HIV infection rates among gay and bisexual men, including in Australia. However, because access to, and use of, HIV prevention strategies varies across subpopulations, some groups of gay and bisexual men have higher HIV rates or are at higher risk of HIV infection, including in Australia, a country where HIV prevention policies have been strong. Moreover, the widening range of HIV prevention strategies – many of which are used in combination – has made it difficult to monitor and evaluate HIV prevention techniques and risk of HIV infection within specific groups.

Drawing on repeat survey data collected between 2017 and 2021, a recent article in AIDS and Behavior analysed the wide range of HIV prevention measures that Australian gay and bisexual men used and identified the level of ‘safe sex’ (‘net HIV prevention coverage’) these men achieved by using any safe sex strategy. These strartegies included not engaging in anal intercourse; consistent condom use; being HIV positive and on treatment with an undetectable viral load and reporting condomless anal intercourse with casual male partners; and being HIV-negative, on PrEP, and reporting condomless anal intercourse with casual male partners.

They also sought to identify which groups of men were at highest risk of HIV infection by virtue of engaging in higher risk sexual behaviours: being HIV-negative or untested, not on PrEP, and having condomless anal intercourse with casual male partners.

The authors found that their respondents’ net HIV prevention coverage increased overall, from 70% to 75%. The rise in prevention coverage during sex with causal partners was driven by increased PrEP use and high levels of viral suppression among respondents living with HIV, which counteracted the drop in condom use over the same five-year period. However, the risk of acquiring HIV, and the prevention methods used, varied by age, sexual identity, how long those born outside of Australia had lived in the country, and the percentage of gay men living in the suburbs in which respondents resided.

Age differences

While respondents aged 25 and younger had the lowest rate of HIV infection, they also had the lowest level of prevention coverage and the highest risk of HIV infection. They were the most likely to report having anal sex with casual partners. While they were most likely to report consistent condom use with casual partners, they were also least likely to use PrEP when having condomless sex with them (however, this age group’s PrEP use in this context more than doubled from 9% in 2017 to 20% in 2021).

Respondents aged 25-44 were the most likely to use PrEP when having condomless sex (this doubled from 19% to almost 40% over the five years), but their consistent condom use dropped by almost half from a high of almost 40% in 2017. This age group’s prevention coverage (71% in 2017) increased slightly, and the proportion of respondents in this age group at higher risk of HIV infection decreased from almost 30% to slightly more than 20%.

The oldest age group (45 and above) had the highest prevention coverage and the lowest proportion of men at highest risk of HIV infection. This group was most likely to be living with HIV and have an undetectable viral load. It was most likely to report no anal sex with casual partners, and, while consistent condom use declined over time, PrEP use by those reporting condomless sex more than doubled, from 12% in 2017 to 31% in 2021.

Country of birth and length of stay in Australia

Australian-born respondents’ HIV prevention coverage increased slightly (from 69% in 2017 to 74% in 2021), and the proportion of these respondents at higher risk of HIV infection decreased (from 31% to 26%) over the same period. In contrast, HIV prevention coverage among overseas-born respondents who had lived in Australia for less than two years stayed the same between 2019–2021 (the only years the survey asked about length of stay), although the proportion of recently-arrived respondents who were at higher risk of HIV infection also dropped. The highest levels of prevention coverage were among overseas-born respondents who had lived in Australia for more than two years (coverage increased from three in four to almost four in five from 2019 to 2021). These highest levels were mainly due to relatively stable proportions of these respondents reporting consistent condom use and no anal intercourse, and to an increase in PrEP use during condomless sex.

Sexual identity

Survey respondents who identified as gay had higher levels of prevention coverage (and lower levels of casual sex with a risk of transmission) than bisexual and other-identified respondents. Men who identified as gay also had higher levels of PrEP use during condomless sex. Gay-identified respondents had a higher proportion of HIV-positive respondents with undetectable viral loads who reported condomless sex. Respondents who were bisexual or had another identity were more likely to report consistent condom use.

Living around other gay men

Prevention coverage among respondents who lived in suburbs with more than a 10% gay resident population was consistently high, increasing from 73% in 2017 to 88% in 2021. In suburbs with more gay residents, this was driven by an almost two-fold increase in PrEP use by HIV-negative respondents who reported condomless sex with casual partners (23% in 2017, and 52% in 2021) and in HIV-positive respondents with undetectable viral loads who had condomless sex. The proportion of respondents living in suburbs with more gay residents who reported having sex with a higher risk of HIV infection dropped from one of four (25%) to roughly one in ten (11%) over the five years.

In contrast, improvements in prevention coverage were smaller among respondents from suburbs with a less than 10% population of gay residents (from 70% in 2017 to 74% in 2021), although their PrEP use during condomless sex more than doubled over the five years the data were collected. However, they were consistently more likely to report sex with a higher risk of HIV infection than were respondents from suburbs with more than 10% of gay residents.

Conclusion

Although Australia’s HIV provision remains strong, inequalities in net HIV prevention coverage, in HIV risk, and in the range of prevention strategies used continue. Higher levels of HIV risk and lower levels of prevention coverage among younger gay and bisexual men, men who identify as bisexual, and men living in suburbs with fewer gay men contribute to Australia’s failure to achieve the 95% prevention coverage target recommended by UNAIDS.

The authors recommend that those working to increase HIV prevention coverage in affected communities support access to a range of effective prevention strategies – including condoms, PrEP and undetectable viral load – rather than focusing on single strategies.