Since the mid-1990s, indicators of HIV risk in gay men in Australia have steadily increased but HIV infection rates have not. In Sydney, where behavioural monitoring has been in existence since 1996, the proportion of gay men reporting unprotected anal intercourse (UAI) with casual partners has increased from 14 percent to 25.7 percent in 2001. Rates of gonorrhoea have increased several-fold in the gay communities of Sydney and Melbourne, and this increase has also occurred for anal gonorrhoea, an indicator of unprotected anal sex.
There are early indicators that suggest that Sydney may also be on the verge of a syphilis epidemic in gay men. Internationally, similar trends in HIV risk behaviour and sexually transmitted infections (STIs) have occurred. In some locations, such as San Francisco and Toronto, this has been accompanied by increases in HIV incidence but this has not been a consistent finding.
These data pose an obvious question: why has Australia not seen an increase in HIV infection in recent years? There are several factors that may have acted to prevent a resurgence.
First, levels of testing for HIV in people at risk of HIV in Australia are among the highest in the world. Coupled with the second factor, the emergence of effective HIV therapies, this means that a large proportion of people with HIV in Australia are diagnosed, and are receiving HIV therapy. More than 50 percent of people with HIV attending medical practices in Australia have undetectable viral loads, and this has probably led to decreased infectiousness of people with HIV.
Third, behavioural studies suggest that much of the increase in UAI with casual partners has occurred in situations of modified risk, such as HIV-negative men assuming the insertive position in anal sex.
However, there are a number of new social and medical conditions that may impact upon Australia’s continuing success in HIV prevention.
Among gay men, there is evidence that testing rates may be decreasing. In addition, new treatment guidelines recommend delaying therapy in many people with HIV, which will mean that a larger proportion of people with HIV will have detectable viral loads. Changing attitudes about the consequences of HIV infection may mean that further changes towards higher risk behaviours will occur.
Australia’s needle and syringe program has kept HIV infection levels very low among injecting drug users, but the continued success of this program is threatened by politically motivated attacks, even in the face of the obvious international evidence of the decimation of injecting drug-using populations where ready access to clean needles is not available.
External factors also loom large as HIV epidemics take off in our near neighbours of Papua New Guinea and Indonesia. Responding to the crisis on our region will be one of our greatest challenges and will require strong leadership.
We should be in no doubt that Australia’s success in controlling HIV is fragile. Past investment in HIV policy in Australia has been extraordinarily successful in minimising the personal, social and economic impacts of HIV. The continued success in HIV prevention requires continuing investment in prevention. The HIV epidemic in gay men in Australia, and in many other industrialised countries, is in an easily disturbed equilibrium, held in check by effective antiretroviral therapy, complex behavioural risk reduction strategies, and high rates of testing and treatment.
Australia cannot simply assume that its successes in HIV prevention will continue. Despite some promises in the field of HIV vaccine research, a safe and effective vaccine remains a hope rather than a reality. An optimistic view is that we may have a highly effective vaccine widely available within five to 10 years, but it is equally possible that the goal of an effective vaccine will continue to elude us.
The price of continued success in HIV prevention is continued investment in the model of HIV prevention that has served Australia so well. This model is one of engagement and involvement of all players across a formalised partnership of government, health care workers, researchers, and members of affected communities. All members of this partnership need to remain engaged and the need for a strong and unified federal government strategy remains crucial.
On the world scale of HIV epidemics, Australia is currently an island of calm. This is not through luck, but through good planning and policy. Any reduced commitment to HIV prevention at this crucial time could well put this success at risk.
Associate Professor Andrew Grulich (pictured) is president of the Australasian Society for HIV Medicine (ASHM). This is an edited version of his address to the ASHM National Conference held in Sydney last month.