Dr. Scott Gottlieb told CNBC on Monday that the current spike in Covid infections caused by the more contagious Delta variant could be the “last wave” of the virus in the United States.

“I don’t think Covid will be epidemic all through the fall and winter. I think this is the final wave, the final act, provided we don’t have a variant that pierces the immunity of a previous infection.” or vaccination, “the former Food and Drug Administration commissioner told the Squawk Box.” This will likely be the wave of infections that will end up affecting people who refuse to be vaccinated. “

Gottlieb said Americans still have a few months to take pandemic-related precautions, especially in the northern US states, as cases peak in the south until the wave of infections subsides again.

“I think this is going to be a difficult time,” he said. However, Gottlieb said the contagious nature of the Delta variant and the increased vaccination rates could change the course of future infections.

“We’re going to get some population-wide exposure to this virus, either through vaccination or through previous infection, which at this rate will stop circulating at that rate,” said Gottlieb, who ran the FDA from 2017-2019 under the Donald Trump administration.

According to a CNBC analysis of Johns Hopkins University data, the seven-day average of new daily coronavirus cases in the US is 108,624. That is 36% more than a week ago. The highly communicable Delta variant, first identified in India, accounts for 83% of all sequenced Covid cases in the country, according to estimates by the Centers for Disease Control and Prevention.

Given the surge in infections to coincide with plans to reopen schools in the fall, Gottlieb warned that schools may have to start the year with more stringent containment measures such as masking, testing, physical distancing and collecting through capsules.

“The goal must be to keep schools open and open, and we cannot expect us to change all behaviors about what we do about mitigation in schools and achieve the same result, in particular with this new “Delta variant, which is more contagious and will inevitably be difficult to control in schools,” said Gottlieb, who sits on the board of directors of the Covid vaccine manufacturer Pfizer.

Large numbers of vaccinated people can still congregate at a venue if there is an “appearance of a bubble,” he said. Vaccinated people who become infected are likely to get the virus from unvaccinated people and then spread it to close contacts after being contagious for a brief window of time, the former FDA chief said.

Gottlieb said wearing a higher quality mask like the KN95 mask is more important now as the virus is known to spread through aerosols rather than droplets. A good quality cloth mask only offers 20% protection from transmission, and most people don’t wear it well, he said.

“We’re bringing a kind of alpha mindset into a delta world, and it’s not going to work,” said Gottlieb, referring to the alpha coronavirus variant that was first discovered in the UK last year. “We will see that this delta variant is more difficult to control,” he said.

Disclosure: Scott Gottlieb is a CNBC employee and a member of the board of directors of Pfizer, genetic testing startup Tempus, health technology company Aetion, and biotechnology company Illumina. He is also co-chair of the Healthy Sail Panel of Norwegian Cruise Line Holdings and Royal Caribbean.