Will there be a 2nd wave of COVID-19 infections? WHO warns of 'immediate 2nd peak'

SAN FRANCISCO -- Health officials have long been warning of a second wave of coronavirus cases to come sometime in the fall, but a global spike may come even sooner.

While new infections may be on the decline in Europe, Asia and North America, the World Health Organization's Dr. Mike Ryan warned that trend may change with loosened restrictions.

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Ryan predicted we may see a "second peak" even before the expected second wave in the fall.

"We need also to be cognizant of the fact that the disease can jump up at any time. We cannot make assumptions that just because the disease is on the way down now, it is going to keep going down," he said. "We may get a second peak in this (first) wave."

He advised leaders to "continue to put in place the public health and social measures, the surveillance measures, the testing measures and a comprehensive strategy to ensure that we continue on a downwards trajectory and we don't have an immediate second peak," as reported by Reuters.

In addition to a potential more imminent peak, epidemiologists also believe we'll see a wave of new COVID-19 infections in the fall and winter, as is typical with other strains of coronavirus.

Marc Lipsitch, a Harvard epidemiology professor, said in an interview with the American Medical Association he expects warm, summer weather to contribute to a decline in coronavirus transmission, but only by about 20%.

"That's only enough to slow it down, but not enough to stop it," said Lipsitch. "We will have a harder time controlling coronavirus in the fall ... and we will all be very tired of social distancing and other tactics. The hard thing will be to keep enough of it to protect our ICUs and keep the number of cases from flaring up."

In California, Gov. Gavin Newsom has emphasized the state is prepared to return to stricter stay-at-home measures if the rate of COVID-19 transmission increases.