Mass vaccinations and natural protection from those already infected are likely to prevent a fourth wave of Covid-19 in the United States, Dr. Scott Gottlieb, former commissioner of the Food and Drug Administration, said Sunday.
"We're talking about some form of protective immunity in about 55% of the population," Gottlieb said on CBS's Face the Nation. "There's enough of a backstop here that I don't think you're going to see a fourth surge."
About 81 million people have had at least one dose of a vaccine, a number that is going up significantly every day. In addition, about 29 million people have tested positive for the virus and recovered, and tens of millions more have had Covid-19 without a positive test and have some natural immunity.
Still, the US will continue to see Covid-19 cases and deaths, Gottlieb cautioned, particularly as a dangerous variant first identified in the United Kingdom spreads.
"I think what you could see is a plateauing for a period of time before we continue on a downward decline -- in large part because (the UK variant) is becoming more prevalent, in large part because we're pulling back too quickly, with respect to taking off our masks and lifting the mitigation," he said.
Gottlieb also warned that the emergence of virus variants could change the nation's trajectory.
"The only thing that can be a real game changer here is if you have a variant that pierces prior immunity, meaning it reinfects people who've either already been infected or who have been vaccinated," he said.
Gottlieb's comments come as the number of US Covid-19 cases has plateaued at about 50,000 new cases per day over the last seven days. Several experts have warned of another surge as the US races to vaccinate and stay ahead of the variant.
"This is crunch time," Dr. Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine, told CNN on Saturday. "This is going to be our most difficult period right now in terms of seeing who wins out."
With about a quarter of all Americans having received at least one dose of a Covid-19 vaccine -- and about 13% fully vaccinated -- doubling down on safety measures now is what could help curb another surge, experts have repeatedly stressed.
"If we can hang on another month, another six weeks, that's going to make a huge difference," Hotez added.
However, air travel is hitting pandemic-era records and spring break crowds are swelling. In Miami Beach, officials declared a state of emergency Saturday in response to crowds the mayor says have been "more than we can handle."
And at least a dozen governors and multiple local leaders have eased restrictions this month, while several have done away with mask mandates completely.