AusDoc 12th Dec | Page 38

38 CLINICAL FOCUS

38 CLINICAL FOCUS

12 DECEMBER 2025 ausdoc. com. au
Therapy Update

Measles immunisation for travel: how young should we go?

Travel medicine
Professor Nick Zwar is a GP and executive dean at the faculty of health sciences and medicine, Bond University, Gold Coast, Queensland.
Given the falling and delayed vaccine coverage and the resumption of international travel, there are significant numbers of Australian children at risk of contracting measles.

MEASLES has been in the news with outbreaks occurring globally at levels not seen for decades. Worldwide, there were an estimated 10.3 million cases of measles in 2023, a 20 % increase from 2022, according to estimates from the WHO and the US Centers for Disease Control and Prevention. 1 The WHO estimated that 107,500 people died from measles in 2023, with the majority of deaths occurring in low-income countries. However, with falling vaccination coverage in developed countries, measles outbreaks are possible when travel-related measles cases are in contact with

Victoria, and more recently in the Pilbara region of WA. Countries in our region where Australians like to travel, such as Vietnam, Cambodia, Laos and Malaysia, are also experiencing outbreaks, and recent cases in SA and WA have been linked to travel to Bali. 3-5
Disrupted protection
The WHO recommends that two-dose
vaccination coverage must be above 95 % to prevent outbreaks. 6 However, many countries, including Australia, are falling short of the optimal level of uptake. Immunisation coverage has been falling since 2020. According to the National
international travel, there are significant numbers of Australian children at risk of contracting measles. Exposure can occur with travel to a high-risk destination, contact with an infected returned traveller, or from measles spreading in a suboptimally vaccinated community. One of the complications of measles is sub-acute sclerosing panencephalitis( SSPE). The risk of this condition is higher( 18 cases per 100,000) if the measles infection occurs in a child aged less than five. The latent period for development of SSPE after measles can be as long as 7-10 years, and the clinical course is devastating, with no prospect of survival. 9
at-risk populations. In 2019, the US lost its status as a country where measles had been eliminated, following a large out-
Centre for Immunisation Research and Surveillance Annual Immunisation Coverage Report 2023, the proportion of two-
Timing of vaccination
In this context, there is lively discussion
break in New York( nearly 1300 cases) and cases in 30 other states. 2
Australia experienced a significant
year-olds who had received two doses of the measles vaccine was 93 %. 7 Decreased levels of on-time childhood vaccination
about the timing of measles vaccination. Currently, the Australian schedule for routine measles vaccination is the MMR
measles outbreak in the early 1990s with
are a worrying post-COVID-19 pandemic
vaccine at 12 months and the MMR-vari-
over 2000 cases in both NSW and Queens-
phenomenon. In 2024, one in three chil-
cella vaccine at 18 months. In the context
land and smaller numbers in other states.
dren was late to receive their first dose of
of low risk of exposure prior to vaccina-
Although not reaching these previous
the MMR vaccine. 8
tion, this schedule makes sense. The rea-
case numbers, 2025 has seen significant
Given the falling and delayed vac-
soning includes that immunisation may
outbreaks, predominantly in NSW and
cine coverage and the resumption of
be less effective if given at a younger