Recorded cases of influenza in the first quarter of the year have hit an all-time high, as the state enters “uncharted territory” during the winter peak flu season.
There were more than 10,000 laboratory-confirmed influenza cases across Victoria during the first quarter of this year, a year-on-year surge of more than 47 per cent and the highest number since regular quarterly reporting began in 2000.
There were 5476 cases of lab-confirmed influenza during the first three months of 2024, according to federal government figures, and just 3557 cases the year prior.
Ten years ago, in 2015, only 660 influenza cases were reported during the first quarter of the year.
Victoria’s recent summer-to-autumn flu spike is part of a broader national trend, as influenza detection has been on the rise outside the traditional cold and flu season – between May and September – since the end of the COVID-19 pandemic.
Nationally, Australia has grappled with its highest first-quarter influenza case load ever, with more than 47,000 confirmed cases this year – up 55 per cent compared to the same three-month period in 2024.
Royal Australian College of General Practitioners president Dr Michael Wright says he is particularly concerned about a steady decline in vaccination coverage in over-65s.Credit: Dion Georgopoulos
Australian hospitals have also detected a jump in influenza B – the strain more likely to cause severe disease in children – after very few confirmed cases last year.
Influenza, more commonly known as the flu, is characterised by a fever, chills, cough, sore throat, a runny or stuffy nose, aches and fatigue. Children can often experience nausea, vomiting and diarrhoea.
Adults are most infectious during the first three to five days of their illness, while children can remain infectious for up to 10 days.
Royal Australian College of General Practitioners president Dr Michael Wright said an early start to the flu season was an “ominous sign”.
“More than 1000 deaths last year involved the flu,” Wright said. “More than 4200 people were admitted to hospital. It’s easy to see how a perfect storm of infection could push our health system to near breaking point.”
The second-generation GP said he was particularly concerned that vaccination rates had steadily declined among patients aged 65 and older. About 61 per cent of individuals in this age group received a flu shot last year, down from almost 70 per cent just three years ago.
“Please spread the word to people in your life, including friends, family and colleagues – the flu is a serious illness and this year is looking especially dire, so let’s work together and get vaccinated.”
While anyone can catch influenza, people aged 65 and older – as well as children under the age of five, Aboriginal and Torres Strait Islander people and pregnant women – have a higher risk of severe illness.
Chief Health Officer Tarun Weeramanthri said Victorians needed to get vaccinated every season: “It’s critically important to stay up to date with your shots – the influenza virus changes throughout the year, and that’s why new vaccines are developed for each season.”
Victorian Health Minister Mary-Anne Thomas repeated the call for vaccination, also urging parents to take advantage of the government’s free RSV immunisation program.
Senior pharmacist Peter Guthrey, from the Pharmaceutical Society of Australia, said people living with conditions like heart disease, diabetes or asthma also fell into the higher-risk category.
Dr Jules Bayliss, a medical director at vaccine manufacturer CSL Seqirus, said the last time there were this many influenza cases early in the year was 2020 when Australia closed its international borders.
“So we are in a little bit of uncharted territory with respect to what high notifications now mean for later in the year,” Bayliss said. “Certainly, we’ve made sure that our vaccines are available early for people to get vaccinated because there is more flu circulating.”
It is recommended that everyone aged six months and older receives an annual flu vaccine to protect themselves and others from influenza. High-risk cohorts are eligible for a free shot thanks to the national immunisation program.
Bayliss said there were a few factors behind the unprecedented January-to-March figures.
“The first is that testing for the flu has increased,” she said. “With more testing, you’ll find more cases. The northern hemisphere has also had a really significant flu season and that’s continuing even now, and that’s contributing to the cases we’re seeing here. And what we’ve seen in recent years are decreases in flu vaccine coverage across all age groups.”
Australians are encouraged to call triple zero immediately if they or a loved one develops the flu and experiences shortness of breath, rapid breathing, chest pain or pressure that lasts longer than 10 minutes, confusion, a sudden onset of dizziness or persistent vomiting.
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