Fears of 'twindemic': Here is how flu symptoms differ from Covid-19

There are at least 100 viruses that can cause the common cold, but only four that cause seasonal flu

As influenza season approaches, some Americans, and especially parents, are worried that, if they or their children should become ill, it may not be easy to know which disease they have — the flu or Covid-19.

They are correct. Most symptoms of the two diseases are so similar that, short of a test — or two or three tests — it won’t be possible to know for sure. But there are some clues. (And it is possible to have both infections at the same time; some patients in China this year were found to have both.)

But first: get a flu shot.

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