Suboptimal mpox vaccination coverage in Australia, study suggests

By Rebecca Jenkins

As few as 10% of Australian men who have sex with men (MSM) may be vaccinated against mpox, an analysis suggests, revealing an immunity gap that could lead to future outbreaks.

Limited Australian data on mpox disease epidemiology and vaccine uptake have been published since the global outbreak began in 2022, researchers led by the National Centre for Immunisation Research and Surveillance (NCIRS), Sydney, wrote in eClinicalMedicine.

In the first study to address this knowledge gap, their analysis using National Notifiable Diseases Surveillance System data found 1579 mpox cases were reported from May 2022 to December 2024.

Most recorded mpox cases were in males (99.2%) and in those aged 20 to 49 years (85.6%), 45.2% of cases were unvaccinated and 7.4% were hospitalised, they reported.

In terms of epidemiological patterns, Australia recorded a small mpox outbreak in 2022 and a large outbreak in 2024, contrary to the trends in most high-income countries, which saw large outbreaks in 2022.

The researchers said this possibly reflected effective initial containment through a nationally funded immunisation program launched in 2022, together with extensive contact tracing in sexual networks of gay, bisexual and other men who have sex with men (GBMSM) with strong gay, bisexual and queer (GBQ+) community connections.

From January 2022 to December 2024, 114,966 mpox vaccine doses were administered to 66,982 people, mostly male (94.2%) and aged 20 to 49 years (75.6%), according to the researchers’ analysis of Australian Immunisation Register data.

Using detailed denominator analysis, the researchers estimated that the two-dose coverage was 15% (13.7% to 16.6%) among men identifying as GBQ+ and 9.6% (8.4% to 11.2%) among MSM.

Study senior author Associate Professor Frank Beard, Associate Director of Surveillance, Coverage, Evaluation and Social Science at the NCIRS, said the new estimates of mpox vaccination coverage in the overall GBMSM population were much lower than in previous surveys. These had found between 41.5% and 72.5% coverage among community-recruited samples that included a high proportion of men with strong GBQ+ community connections.

‘This suggests that awareness and vaccination uptake may be much lower in men who have sex with men without strong GBQ+ community connections,’ he told Medicine Today.

‘While rates of mpox disease in Australia are currently relatively low, our estimates indicate mpox vaccination coverage is suboptimal, suggesting a risk of future outbreaks.’

Professor Beard encouraged GPs to offer mpox vaccination to all sexually active GBMSM alongside other recommended vaccinations, such as human papillomavirus, hepatitis A, hepatitis B, and meningococcal ACWY and B vaccinations.

‘Where appropriate, GPs could consider engaging via local trusted community channels to increase awareness of the recommended vaccinations for GBMSM and their availability, as many are free in Australia,’ he said.

The Australian Immunisation Handbook also recommended offering the mpox vaccine to other at-risk groups, including sex workers, people living with HIV and other people who may be involved in the sexual networks of GBMSM, such as transgender and gender-diverse people.

eClinicalMedicine 2026; https://doi.org/10.1016/j.eclinm.2026.103903.