By Dr Skye McGregor, Epidemiologist, and Jonathan King, Epidemiologist, The Kirby Institute

A late diagnosis of HIV has important individual and public health implications. Late HIV diagnoses are characterized by a CD4+ t-cell count of 350 cells or less per cubic millimeter of blood at diagnosis (CD4+ t-cells are immune system cells that are attacked by HIV). People diagnosed late are often at an advanced stage of disease and are more likely to experience poorer health outcomes. To achieve equity of outcomes for people living with HIV, it is crucial that we focus on timely HIV diagnosis and reduce the proportion of late diagnoses. Timely diagnosis also ensures that people can commence treatment early and achieve viral suppression and an undetectable viral load, to effectively reduce the risk of onwards transmission of HIV to sexual partners to zero. To reach equity, we need to understand who is more likely to be diagnosed late and use this information to ensure appropriate and accessible HIV testing options are available to those who need them.

In 2020, 44% of new HIV diagnoses in Australia were classified as late diagnoses, up from 32% in 2016. Looking in more detail, the data show that among people born overseas diagnosed with HIV in 2020, 52% were diagnosed late, compared to 37% among people born in Australia. While country of birth is a poor proxy for cultural and linguistic diversity as this indicator may incorrectly classify people or not capture all people from cultural and linguistically diverse backgrounds, it does indicate that people born overseas are missing out on timely HIV testing.

Other data relating to late diagnoses that are useful in understanding inequity in HIV testing, are the estimates for the proportions of people who are living with undiagnosed HIV. Ensuring this group has access to HIV testing and therefore timely diagnosis, will help reduce the number and proportion of people diagnosed with HIV late. In 2020, an estimated 2,610 people, or 9% of people living with HIV, were living with undiagnosed HIV. And while this proportion has decreased since 2016, when it was 12%, the change has been slower than required to achieve national and international targets of 95% of people living with HIV diagnosed by 2030. When thinking about this in relation to people from culturally and linguistically diverse backgrounds, information broken down by region of birth is helpful in understand where the biggest gaps are. In 2020 the proportion of people born in South-East Asia, Latin America, and Sub-Saharan Africa, living with undiagnosed HIV was 28%, 22% and 13%, respectively. Concerningly, for people born in Latin America, this proportion has not decreased over time and has plateaued. These data show that Australia needs to invest more in targeted and culturally appropriate testing programs to ensure that all Australians have equitable access to timely HIV diagnosis, and appropriate care and support.

While these data focus on region of birth, there are considerable limitations in using this as an identifier of cultural and linguistic diversity. For example, country of birth doesn’t take into account cultural connectedness of people born in Australia to overseas born parents. Many Australian-born people may live and/or work in communities with strong cultural affiliations associated with their cultural heritage originating outside of Australia. The use of country of birth also doesn’t consider the diversity of countries included that may not be classified as culturally and linguistically diverse in the Australian context. Work is currently underway to improve national HIV surveillance data collection, with the aim of providing more nuanced data relating to people from culturally and linguistically diverse backgrounds. This will help support the development of tailored public health programs and to improve equity in the Australian response to HIV.

You can also listen to Dr Skye McGregor’s podcast ‘Late HIV diagnoses among people from a culturally and linguistically diverse background in Australia’ here.