How To Tell the Difference Between COVID and Seasonal Viruses

By Dr. J.E. Williams | | Reading Time: 3 minutes

Man explaining flu symptoms COVID and seasonal viruses

The flu season is just starting, and with COVID and seasonal viruses present, already there’s an increase in influenza activity. The dominant strain this year is influenza A, subtype H3N2v. It’s a variant (denoted by the small “v”) of the swine flu pandemic strain H1N1 of 2009. And it has the potential to cause severe disease in humans. 

Flu season starts in the Southern Hemisphere before heading north. Look to Southeast Asia and Australia for clues on how bad flu season could get. In the first years of the COVID-19 pandemic, influenza cases were unusually few and mild down under, but not so in 2022. 

Flu cases surged in Australia for the first time since the pandemic. A nasty flu season with a COVID surge driven by new highly infectious SARS-CoV-2 variants may cause a “twindemic.” 

We never know precisely how a winter flu season will play out. But this year’s signs suggest more cases of “flurona,” getting the flu and COVID simultaneously.

Sings of infection, COVID and Seasonal Viruses

Which Virus Is Making You Sick? 

As we enter the cold and flu season with new aggressive SARS-CoV-2 pandemic variants already infecting people, it’s essential to know which virus is making you sick. 

For mild cases, it’s difficult to tell the difference based on symptoms because symptoms are similar. But telltale indications can help you distinguish one from the other. 

The three main symptoms of a common cold are nasal congestion or stuffiness, a runny nose, and sneezing. You may have a scratchy throat and slight body aches. But you won’t have a fever. 

Flu symptoms come on suddenly. You feel sick and could have a fever above 100 F. Other symptoms include severe fatigue, weakness, headaches, and a dry cough. 

Respiratory Syncytial Virus (RSV) is another common virus that causes cold-like symptoms. Typically, symptoms are mild, much like a cold. However, it can be life-threatening in young infants and the elderly. 

COVID takes its time after exposure. The first symptoms don’t appear until about one week after infection. Many only have mild symptoms. But COVID symptoms can come on hard and strong for others. Consider COVID if you have a high fever and chills, a dry cough, fatigue, and muscle pain. Many, though not all, lose their sense of taste or smell.

Symptom Comparison Chart

Runny Nose
Sore Throat
Phlegmy Cough
Dry Cough
Fever Chills
Body Aches
Loss of taste or smell
No appetite
Shortness of breath

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COVID and Seasonal Viruses Tests

The only way to know what virus you have is to get tested. 

If you know you were exposed to COVID, and have the typical symptoms of COVID, do a rapid nasal or throat home swab test. If it’s negative, repeat in 5 days. That’s because it takes a week or longer for SARS-CoV-2 viruses to replicate enough after exposure to show up on a test. 

If you’re unsure if you have the flu or COVID, or are concerned you may have both, get a combination test. LabCorp OnDemand will send you a COVID 19+Flu+RSV home test collection kit. It’s a PCR test, not a rapid test, so you must send the sample to the lab. Results are available in two days. 

Quest Diagnostics offers a SARS-CoV-2 and Influenza A and B nasal swab test. Order on your own online with QuestDirect

You can also order tests from Quest through the Ulta Lab portal on my website. 

To take the guesswork out of your health concerns about infection get tested. If you have moderate to severe symptoms, don’t wait.

Get tested as soon as possible.