A 35-year high in pertussis cases has sparked concern among health professionals and the public alike. The latest data reveals a disturbing trend: declining childhood immunization rates are linked to the highest number of whooping cough notifications since national monitoring began.
The Impact of Declining Vaccination Rates
According to the Productivity Commission, vaccination numbers have fallen to their lowest in a decade, with a corresponding rise in pertussis rates across all Australian states and territories. The Report on Government Services (RoGS) for 2024-25 paints a worrying picture, showing that the proportion of fully immunized children under the National Immunisation Program was among the lowest since 2015-16.
In that year, the immunization rates were 91.6% for one-year-olds, 89.8% for two-year-olds, and 93.3% for five-year-olds. However, in 2024-25, the number of whooping cough notifications reached an unprecedented high of 792.1 per 100,000 children, surpassing all previous records since monitoring began in 1991.
The Productivity Commission attributes this situation to various factors, including decreasing vaccination coverage, waning immunity, and reduced exposure to whooping cough during the COVID-19 pandemic.
A Closer Look at the Numbers
Among children up to 14 years of age, the vaccination rates for the previous year were as follows:
- Pertussis: 792.1 per 100,000 children, a significant increase from 2023-24 when the rate was 201.2 per 100,000.
- Measles: 0.5 per 100,000 children, equivalent to the previous year and consistent with the average annual rate over the past decade.
- Haemophilus influenzae type b: 0.1 per 100,000 children, a steady rate since 2022-23.
Influenza vaccination rates among those aged 65 and over were also concerning, with only 58.4% vaccinated, and even lower among Aboriginal and Torres Strait Islander people at 56.6%.
Associate Professor Paul Griffin, director of Infectious Diseases at Mater Health Services in Brisbane, described these figures as "alarming and concerning." He emphasized that even subtle reductions in vaccination rates over time can lead to substantial changes in population immunity and, consequently, increased risks.
"It's no coincidence that we're witnessing record-breaking numbers of flu, whooping cough, and the resurgence of measles. These diseases are vaccine-preventable, and the decline in vaccination rates is a direct contributor to the rise in cases," Professor Griffin stated.
The Impact on Vulnerable Populations
Professor Griffin highlighted the risks to those who haven't had the opportunity to be vaccinated due to their age or compromised immune systems. "The vaccine for whooping cough is highly effective, but when vaccination rates are low, these vulnerable individuals are at a higher risk of contracting the infection and experiencing severe outcomes. This should be a wake-up call for everyone," he added.
Influenza: A Challenging Year
Last year was particularly challenging for influenza, with the emergence of the new strain Subclade K. Professor Griffin explained that declining flu vaccination rates across most age groups significantly alter population susceptibility. While the flu vaccine may not prevent infection, it moderates the severity of illness, reducing the likelihood of hospitalization.
"Our health system has limited resources and is often stretched to capacity. Higher flu vaccination rates could keep a significant portion of the population out of hospitals and GP clinics, improving the overall functioning and capacity of our healthcare system," he said.
Addressing Barriers and Misinformation
Professor Griffin acknowledged that influenza is often underestimated, especially post-COVID. He emphasized the need to address the barriers and challenges preventing higher vaccination uptake, suggesting a more proactive approach to understanding and overcoming these obstacles.
"Vaccination information can be a minefield, and the spread of misinformation, even from within the medical field, is a significant concern. We must ensure that people receive reliable information from trusted sources like GPs, pharmacists, and nurses, who can guide them towards making informed decisions about their health," he concluded.
The Report on Government Services 2026 provides further insights into the primary and community health sector's response to these challenges.
