Dr. Scott Gottlieb told CNBC on Monday that he believed vaccinating children against Covid was a crucial step in changing the way many Americans see the coronavirus in the future.

“I think the reason a lot of people overestimate the risk of the coronavirus or worry even if they are vaccinated is that the children are still at risk,” the former Food and Drug Administration commissioner said “Squawk- Box.”

“Once adults can vaccinate their children, the fear of a breakthrough infection – knowing you are unlikely to get very sick, your chances of getting very sick are very slim if you are vaccinated, but you could bring it back into the house – I think this will slowly resolve, “he added.

Gottlieb, who is now on the board of directors at Covid vaccine maker Pfizer, admitted the process will be a “slow development,” especially after the highly transmissible Delta variant led to a surge in new Covid infections, hospital admissions and deaths in recent months has led.

“We’ve just spent a year, a year and a half preventing every single infection. We will evolve to a place where it is an endemic virus where it becomes a way of life or a fact of life. If you will. It will be an evolution. It won’t happen overnight, “Gottlieb said, emphasizing that simply vaccinating US adults is not enough to fully make the psychological transition.

“It will be when we can vaccinate the children, when the prevalence goes down, when hospital admissions and deaths go down, and they will. They will be at the far end of this delta wave,” he said.

Pfizer’s vaccine could be available to children ages 5-11 by Halloween after the company said last week that it produced a “robust” immune response in studies with this cohort of children and planned to share its data with regulators to submit. The company’s shot is currently available to children ages 12-15 under an emergency permit, while it is fully licensed for those aged 16 and over.

Moderna, which has received emergency approval for its Covid vaccine for people aged 18 and over, is also conducting studies on younger children.

New Covid cases are starting to decline again in the US, with the seven-day average of new infections every day a CNBC analysis of data from Johns Hopkins University at 119,598. That is 19% less than a week ago. However, the seven-day average of new daily deaths remains around 1,987, according to CNBC analysis. Deaths tend to delay infections by a few weeks.

“We’re still really in the middle of it,” said Gottlieb, who headed the FDA in the Trump administration from 2017 to 2019.

While the Pfizer director kept stressing the vital role vaccines play in protecting against Covid, he also emphasized treating coronavirus drugs, especially when it becomes endemic like seasonal influenza.

Existing therapeutic options include antibody treatments such as Regeneron and Eli Lilly, and Gilead Sciences’ antiviral drug Remdesivir, which is administered intravenously. Pfizer and Merck are currently investigating their own oral antiviral treatments for Covid.

“Roche has a drug that is also in advanced development, a little further behind but looks very promising, and then there are a number of drugs that are in earlier development and designed specifically for SARS-CoV-2 became.” scientific name for the novel coronavirus, said Gottlieb. “I think we’re going to have an antiviral.” He added, “This is not a difficult virus to stun in terms of replication.”

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.