Can you get influenza twice in a month? A GP’s take!

Overview

Technically, yes.  While your body does build up immunity to the specific strain of flu you've just battled, there's more than one strain circulating at any given time.   It's that time of year again when sniffles turn into sneezes, and a tickle in your throat becomes a full-blown cough.  Flu season is upon us, and with it comes a whole host of questions. One that often pops up, especially when you're feeling particularly under the weather, is: can you actually get the flu twice in such a short span of time, like a month? The answer, like most things in medicine, isn't a simple yes or no.  

Understanding flu in Australia

1. Influenza viruses cause flu — these are mainly influenza types A and B. Influenza viruses can change often, which is why new strains appear each year which is Even if you've been vaccinated against the flu one year, it will likely not protect you from new strains in the next year.
2. Influenza A can cause bigger outbreaks and pandemics (e.g., H1N1 "swine flu").
3. Influenza B usually tends to spread later in the winter season, but it can still make people very sick.
4. In Australia, flu season most often tends to peak around the winter months (June–August), although outbreaks can also happen outside of these typical months.
5. Different strains of influenza can often circulate together. For example, sometimes influenza A (H1N1) and influenza B strains may both spread in the same winter.
6. The flu is actually different to COVID-19 and the common cold. COVID-19 tends to cause loss of taste/smell with earlier strains and can be more severe, while colds generally tend to be milder with symptoms of a runny nose and sneezing. But it can sometimes be difficult to tell the difference, which is why it is worthwhile to use self-testing kits that can differentiate between the different types of viral fever.

How flu symptoms can come back

• Misdiagnosis – A bad cold, RSV, or another virus might feel like the flu, but it isn't. Only a test can confirm it, and you can do it conveniently yourself with an over-the-counter multi-test kit found at most pharmacies.
• Lingering symptoms – It's not uncommon to experience fatigue, cough, and muscle aches that can drag on for weeks after you have the flu, making it feel like you're "sick again."
• Secondary infections – Sometimes, after getting the flu, you can develop secondary infections such as sinusitis, bronchitis, or pneumonia (chest infection), and these can feel like having a second round of the illness.

Best way to build up immunity against the flu

The flu vaccine is your best bet, but a healthy lifestyle can also give your immune system a boost. This includes:

• Eating a balanced diet: Fuel your body with the nutrients it needs to stay strong.
• Regular exercise: Get your blood pumping and your immune cells moving.
• Plenty of sleep: Aim for 7-9 hours of quality sleep each night.

 

Flu prevention in Australia

• Get your annual flu vaccine – It's updated each year to cover multiple circulating strains. The best time is April–May, before peak winter.
• Hygiene matters – Wash hands often, wear a mask if unwell, and stay home to reduce spread.
• Boost your immune system – Good sleep, healthy food, hydration, and exercise all help your body fight off infections.
• Stress management: Chronic stress can weaken your immune system.

Home remedies for influenza

While there's no magic cure for the flu, there are things you can do to ease your symptoms and support your body's fight.  These include:

• Rest: Your body needs all its energy to fight the virus, so give it a break!
• Fluids: Stay hydrated to help flush out toxins and prevent dehydration.
• Over-the-counter relief: Certain medicines can help reduce fever and aches.
• Soothing remedies: Honey and lemon can soothe a sore throat, and a warm bath can help ease muscle aches.

When to see a doctor

See your GP or a telehealth doctor if you have:

1. A fever that won't settle
2. Difficulty breathing or any chest pain
3. Severe fatigue or weakness
4. A cough that worsens or doesn't improve
5. Any concerns if you're pregnant, elderly, or have any chronic health conditions (such as COPD, asthma, or diabetes etc)

Doctors can provide a same-day telehealth consult, medical certificates for work, and prescriptions or referrals if needed, which is especially convenient if you're too sick to leave home to go to the doctor's clinic.

Hola Health: support for influenza and recovery

If you are ill with the flu, you can instant consult with an online Hola Health doctor from home. Our experience doctors can check your symptoms and prescribe medicine if needed, and give you a medical certificate for work or study. They can also guide you on how to care for yourself, suggest tests or specialist referrals, and advise when to seek urgent help. This way, you can get quick and trusted care without visiting a clinic.

FAQs

Could my "second flu" actually be something else?

Yes — often it's another virus or a chest infection that's lingering and hard to shake off, but not true influenza.

Can you really catch the flu twice in the same season in Australia?

Yes, it's rare, but it's possible. You could catch influenza A and then influenza B, or different subtypes of A.

How can I reduce my risk of catching the flu more than once?

Make sure you get vaccinated, remember to wash your hands often, and avoid close contact with other people who are sick.

How common is it to get the flu twice in one winter in Australia?

It's uncommon to get it twice, but doctors do see it each year because multiple influenza strains are circulating.

How do I know if it's the flu, COVID-19, or just a bad cold?

The only way is by testing to confirm. Symptoms of each of these can often overlap, so it's safest to check with your GP.

Does getting the flu once give me immunity for the whole year?

Not always. Unfortunately, your immunity is usually specific to the strain you caught, so exposure to another strain can still infect you.

Can you get the same strain of flu twice?

It's less likely, but still possible.  Your immune system is usually pretty good at remembering its enemies.  However, the flu virus is a master of disguise, constantly mutating and changing its appearance. This means that even if you encounter the same strain again, it might have changed just enough to slip past your body's defences.

Can influenza come back after a week?

Sometimes what seems like a second bout of flu is actually just a lingering case of the first one.  The flu can be a real bully, sticking around for longer than you'd like and even bringing some of its friends along, like a secondary bacterial infection.  This can make you feel like you've been hit by a bus twice, but it's not technically a new flu infection.

How long are you contagious with influenza A?

You're most contagious in the first 3-4 days of your illness, but you can still spread the virus for up to a week after your symptoms start.  This is why it's so important to stay home and rest when you're feeling unwell to prevent the spread of the virus to your close contacts.

Is flu A or B worse?

Both can make you feel pretty miserable, but Flu A tends to be the more aggressive sibling, causing more severe symptoms and complications.  However, Flu B can still pack a punch, and both can potentially make you significantly unwell.

Can you still get the flu after vaccination?

Yes, unfortunately.  The flu vaccine is like a wanted poster for your immune system, showing it what to look out for.  But sometimes, a new strain pops up that wasn't on the poster, or the virus changes its appearance just enough to evade detection.  However, even if you do get the flu after having the vaccine, your symptoms are likely to be milder. Think of it as your immune system having a head start in the fight.