Got the spicy cough followed by a bout of flu followed by a seemingly never-ending cold, followed by another bout of COVID-19? Well, there’s a chance it could be down to the way COVID impacts your immune system.


It’s not really a shock that COVID fucks with your immune system: it is a virus after all. But it certainly feels like everyone I know has been almost constantly sick this year, whether it’s from COVID reinfections, a terrible flu season or just a pesky cold.

So what’s happening?

Let’s start simple: what is your immune system?

Your immune system is a network of proteins, organs and cells. Its job? Protecting you from nasty little pathogens. Your immune system recognises pathogens once it’s faced them before, making them easier to fight off.

This is why vaccines are so great: your body is able to have a little suss of the offending pathogen and prepare its immune response against it if you did get sick.

What do we know about COVID and the immune system?

Over the course of the pandemic there have been numerous studies into how COVID-19 impacts the immune system.

One German 2021 study found contracting the COVID virus (known as SARS-CoV-2) “reduces the numbers and functional competence of certain types of immune cells in the blood” according to Science Daily.

The researchers thought this could make people “more susceptible” to secondary infections during and immediately after their contraction of the virus.


In an article for The Conversation, Griffith University research lead in virology and infectious disease Lara Herrero broke down how the body responds to viral infections.

Herrero explained that often with COVID, our bodies are able to “clear” the virus.

But she cited evidence which indicates there are changes to our immune cells after they’re infected with SARS-CoV-2, which can lead to a reduced ability to fight other viruses and pathogens (fungi and bacteria).

Like a lot of COVID research, it’s an area that’s still being explored by the big dogs of science.

A study conducted by scientists back in January found the virus could impact immune cell populations up to 24 weeks after someone had the infection.

Professor Simon Barry, one of the scientists involved in the study, told the ABC that there “are some subtle immune changes which seem to last a long time”.

For example, T cells — an important type of immune cell — took a fair while to get back to normal after a COVID infection.

T cells are where you get an immune memory response, and that’s critical for the next time you see the virus — you want to knock it off before you get any symptoms, or you knock it off quickly so you don’t get many symptoms,” he said.

How can you look after yourself?

We’ve said it once, we’ll say it again: make sure you’re up to date with your vaccines and wear a mask where possible.

Australia is in the midst of yet another COVID-19 wave thanks to a couple new Omicron variants. So let’s look after ourselves and others the best we can.

Image: Ferris Bueller's Day Off