The U.S. has not yet had a "true second wave" of the coronavirus and the country could see a resurgence of the virus in the fall and winter, former Food and Drug Administration Commissioner Dr. Scott Gottlieb told CNBC on Friday.
"I think most peoples' perception is we had one epidemic in New York, in the New York region, we came down the epidemic curve, we had another epidemic in the Sun Belt, so that really looks like and feels like a second wave," Gottlieb said on "Squawk Box." "I do think that we're going to have a third act of this virus in the fall and the winter and it's likely to be more pervasive spread in a broader part of the country."
He added that the virus is likely to spread to rural parts of the U.S., some of which have been "largely unaffected to date." Cases are already beginning to build in the West and Midwest, Gottlieb said, adding that "every community is vulnerable."
He said the coronavirus does not spread like the flu, which one person might pass on to two or three others, he said, but that the virus spreads largely at "super-spreading events" such as large gatherings, especially indoor events.
"Really, an outbreak can happen anywhere," he said.
While daily new cases have fallen steadily for about a month in the U.S., the number of new cases reported every day remains above 40,000 and more than 1,000 people in the U.S., on average, are still dying everyday due to Covid-19. Director of the Centers for Disease Control and Prevention Dr. Robert Redfield said Thursday he'd like to bring the number of daily new cases down below 10,000 and see daily new deaths fall to under 250.
He added that he expects both new cases and deaths to continue to fall as people and officials implement public health guidelines such as mask wearing, hand washing, social distancing and the closing of bars.
"You and I are going to see the cases continue to drop. And then hopefully this week and next week, you're going to start seeing the death rate really start to drop again." Redfield said in an interview with Dr. Howard Bauchner of the Journal of the American Medical Association. "I think we're going to start to see a decline in mortality across the country now next week as we continue to get control of these cases."
Redfield and others, including Gottlieb, have repeatedly warned that the country could be in for a particularly difficult fall and winter. Coronavirus cases could begin to rise again, especially as cold weather forces people indoors, where the virus spreads more easily. And hospitals will need to grapple with the double burden of both treating Covid-19 patients as well as the expected seasonal influenza patients.
Redfield urged Americans yet again on Thursday to get this year's flu vaccine as soon as it's available to mitigate the risk of an overwhelming flu season. Health officials are taking new steps to increase access to the vaccine. Earlier this week, the Department of Health and Human Services announced that it has authorized pharmacists in all 50 states to provide childhood vaccinations, including flu shots.
In Massachusetts, health officials said Wednesday that most students over the age of 6 months must get a flu vaccine this year in order to enroll in classes in January. That makes Massachusetts the first state to require the flu vaccination for all K-12 and college students. The state expects students to receive the vaccination by Dec. 31, unless the student provides a medical or religious exemption.
Disclosure: Scott Gottlieb is a CNBC contributor and is a member of the boards of Pfizer, genetic-testing start-up Tempus and biotech company Illumina. He also serves as co-chair of Norwegian Cruise Line Holdings' and Royal Caribbean's "Healthy Sail Panel."