Flurry of coronavirus reinfections leaves scientists puzzled

Though far from common, some patients developed worse symptoms the second time they became infected with Covid-19.

Doctors treating coronavirus patients have noticed an increasing number of COVID-19 reinfections. Scientists in various countries have reported reinfections, warning that the second bout of COVID-19 will not be necessarily easier than the first.

So far, only two dozen or so reinfections have been confirmed worldwide in a pandemic that has infected more than 30 million people. For now at least, reinfection seems uncommon. But scientists point out that confirming reinfection is no easy task and many cases are missed.