The first AIDS diagnosis in Australia was in 1982, and following the introduction of HIV testing in 1985, cases of newly diagnosed HIV infection peaked at 2,773 in 1987 declining to their lowest level in 1999 (Figure 1). Studies using the back-projection method have estimated that HIV incidence was highest in 1984 (2,890 cases) with a rapid decline in the latter part of the decade. The decline in incidence has been largely attributed to the rapid adoption of HIV prevention practices, including safe sex, and world leading needle and syringe programs.;
Early diagnoses in Australia were characterised by low levels of heterosexual transmission and transmission among people who inject drugs, with most cases diagnosed among men with a history of male-to-male sex (86%). Of the 16,765 newly diagnosed cases of HIV infection between 1984 and 1992, the majority were reported in New South Wales (67%). The contribution of diagnoses due to receipt of blood, blood products, tissue or treatment of haemophilia declined rapidly from 14% in 1985-1986 to 1% in 1991-1992. There has been an average of one mother-child HIV transmission per year over the last 10 years.Reflecting the approximately 10-year period from HIV infection to development of AIDS, AIDS diagnoses peaked in Australia at 909 in 1994. The first antiretroviral drugs for HIV inf
ection became available in Australia in 1987 and were initially used as monotherapy then as dual therapy from 1992, leading to a continuing decline in AIDS and AIDS-related deaths. By the end of 2009 there had been 10,446 diagnoses of AIDS and 6,776 deaths following AIDS.
Between 1999 and 2012 HIV diagnoses in Australia increased by 48%, likely attributed to increases in risk behaviour and confidence in HIV therapies. However, in the 5 years from 2013 to 2017, HIV diagnoses in Australia have decreased by 7%.1 This decrease has been alongside increases in testing, high treatment coverage, and an increased use of pre-exposure prophylaxis (PrEP).1
Figure 1. Newly diagnosed HIV infection in Australia by year