Biomedical prevention of HIV infection

Iryna Zablotska1, John McAllister2

  1. The University of Sydney, Sydney, NSW
  2. St. Vincent's Hospital, Sydney, Darlinghurst, Sydney, NSW

Last reviewed: November 2019

Background

The HIV epidemic in Australia

Australia has a concentrated human immunodeficiency virus (HIV) epidemic. In 2018, sexual contact between men accounted for approximately 70% of new HIV diagnoses; heterosexual exposure contributed 23%, and only 3% were attributable to injecting drug use alone. [1] During 2014-2018, the annual number of HIV diagnoses declined by 23% overall [1], but a more substantial decline (by 30%) was recorded among men who have sex with men (MSM), while no decline was seen in Aboriginal and Torres Strait Islander people (hereafter referred to as Indigenous), heterosexual people or those born overseas. At a closer examination, the decline in cases of HIV infection among MSM was not uniform: in the last 10 years, notifications declined by 21% in Australian-born MSM but almost doubled (from 28% to 52%) among overseas-born MSM. [1] Among heterosexuals, the notification rate in females remained stable during 2013-2017 (between 0.7 and 0.9 per 100,000) and was lower than in males (0.9 vs 7.1 per 100,000 in 2017). Among Indigenous people, the rate of HIV notifications increased by 41% between 2013 and 2016 and was mainly attributed to heterosexual sex and injecting drug use. Among female sex workers, HIV incidence remained stable at or below 0.13 per 100 person-years during 2013–2017 and was 0.13 per 100 person-years in 2017. [1] Similarly, for people who inject drugs (PWID), HIV prevalence has remained low in the past 10 years (at 2.1% in 2017, and 0.7% if MSM were excluded). However, among Indigenous men in these programs, HIV prevalence increased almost five times between 2011 and 2017 (from 0.9% to 4.2% [1]).

Overall, recent declines in HIV incidence and notifications concurred with several key initiatives at the heart of HIV biomedical prevention, specifically:

  • Improved uptake in HIV testing and treatment with simpler HIV treatment regimens. Consequently, 74% of people with HIV infection in 2017 reached viral load suppression, thereby achieving zero risk of onward HIV transmission. [1]
  • Widespread access to HIV pre-exposure prophylaxis. By the end of 2018, 18,530 people, of whom 99% were male, were receiving Pharmaceutical Benefits Scheme (PBS)-subsidised PrEP in Australia. [2] Largely related to PrEP implementation, a 25% decline in new HIV diagnoses was observed among MSM in New South Wales in the 12 months following the commencement of the EPIC-NSW study. [3]

The divergence in rates of HIV infection between the non-indigenous and indigenous Australians possibly relates to a number of factors, including a higher proportion of undiagnosed cases of HIV infection, sexual and drug-injecting practices and, importantly, a slower adoption of biomedical prevention strategies such as treatment as prevention and PrEP in the Indigenous population. [4] Hence, intensive HIV prevention and treatment efforts, including the use of PrEP, are required to reverse this alarming trend. [5]

In other population groups, harm reduction strategies for PWID and HIV infection, and sexually transmissible infection (STI) prevention strategies for sex workers, have been highly successful in keeping the prevalence and incidence of HIV infection at extremely low levels in Australia and among the lowest in the world. Current health promotion and HIV prevention strategies support PWID and sex workers to maintain these achievements, while access to PrEP may expand HIV prevention options. [6]

There are no available recent data about HIV testing uptake and access to biomedical HIV prevention for temporary residents who are ineligible to access Medicare (short-term visitors, international students, skilled workers and some temporary residents awaiting decisions regarding their permanent residency as partners of citizens or permanent residents, asylum seekers and refugees).