Health in 2025: Why measles, whooping cough, HMPV, Covid and bird flu will keep making news
Antimicrobial resistance is making it harder to treat communicable diseases. Photo / Getty Images
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In the first of a three-part online only feature, Dionne Christian looks at the infectious illnesses we’ll continue to read more about as the year progresses. Tomorrow: Climate Change and mental health; Thursday: Risk factors for chronic illness.
Since the start of the Covid pandemic in 2019-20, we’re all more aware of “communicable diseases” – the infectious illnesses that spread from person to person.
Epidemiologist professor Michael Baker says they will always make the news, partly because of the Covid effect – we now realise what far-reaching and life-changing impacts these invisible (at least to the naked eye) agents can have – but also because they are everchanging.
“Non-communicable diseases [things like heart disease, stroke, cancer and diabetes] are the major threats to health in terms of years of life lost, but they are often measured by one data point per year. With infectious diseases, you have to look sometimes day by day and certainly month by month.”
For example, a whooping cough (pertussis) epidemic was declared in New Zealand in November 2024 after 263 cases were reported in four weeks from October 19-November 15, the highest number over a four-week period for the 2024 year to date. Since then, that number has risen to around 2213 cases and, sadly, a baby died during the Christmas break. A highly contagious respiratory infection that can cause serious harm to babies, whooping cough killed three infants in 2023.
Baker says immunisation rates are down, which goes part way to explaining this latest epidemic. Falling immunisation is also making a measles epidemic more likely in New Zealand. About 77% of the population is vaccinated against measles, but to provide effective herd immunity, close to 95% of the population needs to be fully immunised, says Baker.
“It’s 77% coverage overall, but for Māori it’s only 63%, for Pasifika it’s 72%. All those levels are far too low to stop a national measles epidemic. Measles is highly infectious; an infected person might infect 12-15 other people in an unvaccinated population.”
The World Health Organisation has warned that “measles in back”, with the British Medical Journal noting that cases are at a 25 year high in Europe, while North America has joined Afghanistan in dealing with major outbreaks. According to the BMJ, measles kills a child everyday in Afghanistan while in the United States, two people have died including a child with no underlying medical conditions.