Australia is experiencing a significant surge in measles infections, with cases in 2025 nearly tripling the number recorded in the previous year. The national disease surveillance system reports 168 confirmed cases across the country this year, a sharp increase from 57 cases in 2024 and just 26 in 2023. This alarming rise follows a period of exceptionally low transmission during the COVID-19 pandemic, which saw zero cases in 2021.

Medical experts attribute this resurgence to a combination of factors, including a global explosion in measles outbreaks, declining national vaccination rates, and increased international travel. The World Health Organization (WHO) estimated 11 million measles infections globally in 2024, nearly 800,000 higher than pre-pandemic levels. At least 59 countries experienced large-scale outbreaks last year, with a quarter of these previously having achieved measles elimination status.

The global crisis has seen several nations lose their measles-free declarations. Canada, for instance, lost its elimination status in November after reporting over 5,000 cases this year, including two infant deaths. The United States, which achieved elimination in 2000, faces its highest case count in 25 years, with 1,828 infections and at least three confirmed deaths reported by the CDC as of early December, surpassing its 2019 figures.

Dr. Ramya Raman, vice-president of the Royal Australian College of General Practitioners (RACGP), notes that measles had been uncommon in general practice for decades due to effective immunisation programs and herd immunity. However, the current environment has changed, leading to more frequent outbreaks. Dr. Meru Sheel, an infectious diseases epidemiologist at the University of Sydney, highlights that historically, most Australian cases are linked to international travel, either by infected individuals or their family members.

The highly contagious nature of measles poses a significant challenge to containment. With a basic reproduction number (R0) of 12-18, it is far more transmissible than many other infections, including the more infectious variants of COVID-19. Individuals can spread the virus to others the day before symptoms appear and up to four days after the characteristic rash develops, complicating efforts to trace and prevent further transmission.

Australia was declared measles-free in 2014, with cases dropping into double digits the following year before steadily climbing to 284 annual cases by 2019. The pandemic temporarily halted this trend. However, current vaccination coverage in Australia falls short of the Department of Health’s aspirational 95 per cent target. As of August, only 91.63 per cent of children aged 12 months were fully immunised, and rates for older children were even lower, at 89.76 per cent for those aged 24-27 months.

Medical professionals are urging vigilance and a review of vaccination status. Many Australians born before 1989 may have only received a single dose of the MMR vaccine, which studies later showed was often insufficient for adequate immunity, prompting the introduction of a second dose to the routine schedule. Immunocompromised individuals, very young children who are too young for routine vaccinations, and older adults with incomplete immunisation are particularly vulnerable as the virus continues to circulate globally and domestically.

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