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COVID-19 vs. influenza: What's the difference?

Is it the flu or coronavirus? There's one key difference
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(WXYZ) — It’s not just COVID-19 cases that are on the rise. Many Michiganders are surprised to learn they’re sick with the flu and not COVID-19.

I know many patients who were convinced that they had COVID-19 when they were actually sick with the flu. I get that there are similarities when it comes to COVID-19 and the flu because they are both upper respiratory infections.

For instance, both can cause symptoms like runny nose, sore throat, fever, cough, difficulty breathing and body aches.

So how can you tell them apart?

Well, a loss of taste or smell was once a telltale sign you had COVID-19 as this rarely happened with the flu. But those symptoms are not as prominent anymore.

Another indicator was to look at how fast symptoms appeared. Symptoms tend to come on faster with the flu, whereas it can take longer for a person who has COVID-19.

But here’s the bottom line. The only real way to really know if you have the flu or COVID19 is to get tested. Otherwise, it’s very difficult to tell the difference between the two viruses just by looking at symptoms alone as they are nearly identical.

Both the flu and COVID-19 can be asymptomatic, mild or severe. Both can lead to complications like pneumonia, respiratory failure, sepsis, fluid in the lungs, cardiac injury, multiple organ failure and inflammation of the heart, brain, or muscle tissues. Also, both the flu and COVID-19 can be fatal.

Is one virus deadlier than the other? The answer is: yes. COVID-19 appears to cause more serious illnesses, which can lead to hospitalization and death. While the people most at risk are older adults, pregnant women and people with certain underlying medical conditions, we know that severe illness and death can happen even to healthy people.

Also, some people can develop post-COVID-19 symptoms that last weeks or months. And long COVID can happen to anyone, even if their symptoms were mild or asymptomatic.

The good news is that we have vaccines for both COVID-19 and the flu that can help prevent serious illness and death. It is never too late to get either vaccine, especially as we’re seeing the flu season drag on a bit longer than usual and rising cases for both viruses.

Additional Coronavirus information and resources:

View a global coronavirus tracker with data from Johns Hopkins University.

See complete coverage on our Coronavirus Continuing Coverage page.