Influenza (commonly known as the flu) and COVID-19 share similar symptoms as both are viruses and can affect people of all ages.
We explore the key differences between these two viruses and how you can stay healthy when you catch either one.
Fast facts about influenza and COVID-19
- Influenza is commonly known as 'the flu'1
- The influenza vaccine can't give you the flu because it doesn't contain any live virus
- The symptoms of COVID-19 and the flu can be similar, but COVID-19 symptoms include fever, loss in sense of smell or taste an shortness of breath
What you need to know about the flu
The flu is a highly contagious respiratory illness caused by influenza viruses and can affect people of all ages.
It's usually spread by breathing in droplets from coughs and sneezes that contain the virus.
The flu is more serious than the common cold, with severe flu cases resulting in breathing difficulties and pneumonia for some people.
The influenza virus has a unique ability to change its structure surface, which means that even if you got vaccinated last year, your body's immune system may not be able to fight off the changed version of the virus that's circulating this flu season.
Each year, a new flu vaccination is developed that includes protection against four strains of influenza viruses. While it's not 100% effective, the vaccine still provides a high level of protection and can reduce symptoms if you get sick1.
Flu season generally occurs from April to September, but each flu season is unique as some can be more severe or last longer than the year before.
What about COVID-19?
COVID-19 is an infectious disease caused by the severe acute respiratory coronavirus 2 (SARS-CoV-2) virus.
It affects people of all ages, but older adults and people with certain medical conditions are at an increased risk of severe illness2.
Both COVID-19 and influenza are respiratory illnesses caused by different viruses.
Although they share similar symptoms, such as fever, cough, and body aches, different tests are needed to detect each one.
Key differences between the flu and COVID-19
Even though they are both contagious respiratory illnesses, there are some key differences, which include 3:
- COVID-19 spreads more quickly than the flu.
- Compared to the flu, COVID-19 may cause more severe illnesses in some people and require hospitalisation from previously healthy people.
- Compared to those who have the flu, people who are infected with COVID-19 may take longer to show symptoms and may be contagious for more extended periods of time.
Immunisation and practicing prevention measures (like staying home if you're sick or regularly washing your hands) are the best ways you can protect against the flu and COVID-19.
How can I protect myself against the flu and COVID-19?
You can protect yourself from respiratory viruses like COVID-19 and the flu by:
- Learning the difference between the symptoms
- Having COVID-19 tests in your medicine cabinet so you can test in case of illness
- Booking your COVID-19 and influenza vaccine
Vaccination is the best protection from getting viruses and can protect you against infectious diseases.
You can also receive your flu vaccine at the same time as other vaccines, including your COVID-19 vaccine.
It isn't just a flu vaccine, it's the first step to a healthier Winter. Book your flu vaccination below.
References
1Better Health Victoria, Influenza (flu), accessed 31 March 2025
2Australian Department of Health and Aged Care, COVID-19, accessed31 March 2025
3Centers for Disease Control and Prevention, Similarities and Differences between Flu and COVID-19, accessed31 March 2025
4Western Australian Department of Health, Protect yourself from viruses, accessed 31 March 2025