'The second wave has begun,' Vanderbilt infectious disease expert warns about coronavirus spikes

As coronavirus infections continue to rise in a number of states across the country some health experts are warning that the second wave of COVID-19 in the U.S. is already taking place.

“I think the second wave has begun,” William Schaffner, an infectious diseases expert and professor at Vanderbilt University Medical Center, told CNBC Monday.

“We are opening up across the country, but many, many people are not social distancing, many are not wearing their masks and those are the things that will contribute to coronavirus spreading,” Schaffner said.

Weeks after lifting stay-at-home orders, some states are experiencing record numbers of cases and hospitalizations. South Carolina and Alabama both hit single-day records of new confirmed cases Sunday, while Texas is seeing record numbers of hospitalizations. Meanwhile, Oregon last week put a temporary pause on all further reopening efforts after a spike in single-day cases.

New York Gov. Andrew Cuomo (D) on Sunday threatened to halt the reopening of Manhattan and the Hamptons over complaints people are flouting social distancing guidance. New York so far is not among the states currently seeing an increase in cases and hospitalizations.