The Washington Post points out that 82% of covid-19 cases identified so far are mild, basically a bad cold. Virologists are trying to determine: How many more mild cases haven’t been counted? And what factors cause some cases to be mild and others lethal?

There are several coronaviruses that already circulate globally and just cause colds. And there are several that cause more dangerous diseases like SARS and MERS. Covid-19 is new enough that we’re still trying to figure out where it is on the scale between a cold and SARS.

The Los Angeles Times brought up the H1N1 flu, which at first appeared much more deadly than other strains because it was the severe cases that were being counted. Once researchers could go back and find the mild cases, it turned out to be about the same as the typical seasonal flu. A decade since jumping to humans, H1N1 has essentially become just another seasonal flu.

Covid-19 is somewhere in between a cold and SARS, but as mentioned above, we’re still trying to figure out where.

In any case, it’s worth remembering: mild or severe, coronaviruses spread the same way as colds and the flu. Update 2023: Well, we thought it did at the time. Now we know it’s mostly shared, close airspaces. But washing your hands is still a good idea.

Wash your hands. (As Science-Based Medicine points out, a recent study suggests that hand-washing in airports is “probably the single most effective method for preventing pandemics.”)

Cough and sneeze into your elbow instead of your palm.

And if you get sick, stay home if you can.