It seemed that even the most cautious among us couldn’t manage to avoid a sick day or two by the time we emerged from hibernation last winter. For months, a chorus of sniffles and coughs echoed throughout supermarkets, doctor’s offices and workplaces, making it nearly impossible to avoid picking something up.
The 2024 flu season was Australia’s worst on record, surpassing even the intense 2019 season, leaving many of us concerned we could be in for another round of back-to-back bugs. Between January and March, we saw a 50 per cent increase in influenza numbers compared to the same period last year, with over 46,300 lab-confirmed cases, the most ever recorded in the first few months of a new year.
And while predicting flu severity is notoriously challenging, a tough season overseas can sometimes foreshadow what is to come here.
Across the northern hemisphere, hospitals were pushed to their limits as flu cases reached record highs. In the US, it was the worst flu season in 15 years, while the UK saw staggering rates of hospitalisation and death.
“While flu seasons can be unpredictable, we do look at international trends as an indicator,” says Professor Catherine Bennett, chair of epidemiology at Deakin University.
“Given the severity of flu in the US and UK, it’s certainly possible we could face a similar challenge this winter.”
So what happened both here and abroad? Several factors were at play – a mix of aggressive flu strains, lower immunity levels resulting from reduced exposure in previous years, and a slow uptake of flu vaccines.
“For influenza, a significant factor in determining the severity of a winter is whether the flu vaccine is a good match or a poor match for the circulating strain,” explains Associate Professor Sanjaya Senanayake, an associate professor of medicine at the Australian National University.
“This is an issue because the flu vaccine used for this winter will have been designed months earlier, based on the circulating flu strains at that time. That means that if the circulating strains of the flu virus mutate significantly in the following months, then the vaccine and the virus don’t match very well.”
On top of that, RSV (respiratory syncytial virus) and COVID-19 are still circulating, leading to a perfect storm of respiratory illness.
“We are seeing an increased circulation of multiple respiratory viruses globally, and Australia is not immune to this trend. If these viruses peak simultaneously, it could put significant pressure on our healthcare system,” Professor Bennett warns.
What viruses do we need to worry about this winter?
The term ‘quad-demic’ has been used overseas to refer to the surge in four main respiratory illnesses – flu, RSV, COVID-19, and norovirus. And while Australia’s seasons don’t always mirror those on the other side of the world, it’s likely that we’ll see numerous viruses in play.
“During winter, we see a lot of viruses that are more active because the drier winter conditions make it easier for viruses to spread. Additionally, people tend to spend more time indoors and in close proximity to one another, making it physically easier for a virus to spread from one person to another,” says Associate Professor Senanayake.
With a baseline of respiratory viruses already circulating, another difficult year wouldn’t be surprising. Last winter saw a resurgence of whooping cough, our first major spike since pre-pandemic times. Could we see other respiratory infections make a return?
“Last year’s spike in whooping cough reminded us that infections we hadn’t seen for years can return quickly when population immunity wanes,” says Professor Bennett.
“We’re also keeping an eye on adenovirus and metapneumovirus, which tend to fly under the radar but can cause significant respiratory illness, especially in young children and older adults.”
New variants of COVID-19 continue to emerge, and winter is typically a time when case numbers rise. At least one dominant variant is expected to circulate, with the key concern being whether it’s more immune-evasive or severe than previous strains.
“The virus continues to evolve, and while we can’t predict exactly what new variants will look like, history tells us we should expect ongoing mutations.”
The best time to get vaccinated
Timing is everything when it comes to vaccinations. Ideally, flu shots should be received in April or May to ensure peak protection for winter.
For COVID-19, those eligible for a booster should consider getting it ahead of winter. RSV vaccines are now available for vulnerable groups, and those eligible should speak to their doctor about the best timing.
When to seek medical attention for the flu
With so many bugs circulating, it can be hard to know when to ride it out at home and when to seek medical attention. Here’s a general guide:
- If you have difficulty breathing, persistent chest pain, confusion, or bluish lips or face, seek urgent medical help.
- If a high fever lasts more than a few days or symptoms worsen instead of improving, see your GP.
- If you’re in a high-risk group (young children, older adults, pregnant people, or those with chronic conditions), don’t hesitate to get checked.
How to avoid get sick this winter
Prepping your immune system isn’t about dosing up on vitamin C and hoping for the best – it’s about smart, sustainable habits that keep you fighting fit when the cold and flu season hits, says nutritionist Therese Cullen.
“We don’t need to spend a fortune to stay healthy. Instead of overpriced powders and drinks, invest in nutrient-dense whole foods that naturally support your immune system. Citrus fruits, leafy greens, garlic, nuts, and probiotic-rich foods like yoghurt and kimchi are far more effective than trendy and expensive health shots.”
Sleep, stress management, and hydration also play a major role in immunity to help keep you fighting fit.
Prioritise your bedtime
Your immune system performs its best repair work while you’re sleeping, so aim for 7–9 hours of shut-eye each night. Poor sleep can lower your immune defences, making you more vulnerable to infections.
Eat the rainbow
A nutrient-rich diet rich in vitamin C (such as citrus and capsicum), vitamin D (found in egg yolks and fatty fish), zinc (found in nuts, pumpkin seeds, and lean meat), and antioxidants (including berries and leafy greens) helps your immune cells function properly.
Move your body
Moderate exercise, such as walking, yoga, or strength training, helps circulate immune cells throughout the body. Just don’t overdo it – excessive high-intensity workouts can temporarily weaken immunity.
Roll up your sleeve
Make sure you’re up to date with your vaccinations and boosters. A record of these is available on the Australian Immunisation Register (AIR), accessible through your Medicare online account, or you can ask your GP to check.
Stress less
Have you ever noticed you get sick when you’ve had one of those weeks where everything went wrong? Chronic stress increases cortisol levels, which can suppress the immune response. Try meditation, deep breathing, or even a good belly laugh to lower stress hormones.
Get your gut health in order
Your gut is home to approximately 70 per cent of your immune system. Nourish it with fermented foods (yoghurt, kimchi, sauerkraut), prebiotic-rich foods (garlic, onions, bananas), and fibre (whole grains, legumes, veggies).
Stay hydrated
Water helps keeps your mucous membranes (like the lining of the inside of your mouth and nose) moist and effective at trapping germs. Adults should aim for at least 2 litres a day.
Boost vitamin D levels
Low vitamin D levels are linked to a weaker immune system.
“Aim for 10–30 minutes of sun exposure most days (excluding the hottest times of the day), eat vitamin D-rich foods such as salmon and eggs, and consider taking a supplement if needed. A simple blood test can check your levels,” advises Therese.
Ditch bad habits
Smoking, excessive alcohol, and a diet high in ultra-processed foods can weaken immunity. Swap alcohol for herbal teas, limit junk food, and quit smoking and vaping if you can.
Rinse and repeat
Handwashing is one of the most effective ways to prevent infections before they occur. It’s also worth wearing a mask in crowded areas like supermarkets or on public transport.
Consider immune-supporting supplements
If your diet isn’t quite hitting the mark, supplements like probiotics, echinacea, elderberry, and vitamin C may help. Just be sure to check with your GP first.
