(CNN)Child deaths from a preventable illness like Covid-19, no matter how few, are motivation for authorizing a vaccine in children, the US Food and Drug Administration's top vaccine official said Tuesday.
"In this latest wave of Covid-19, particularly down south, there have been thousands of children hospitalized. And, frankly, it's an embarrassment in a developed country to have even 100 children, like we've had, die of infectious disease that's preventable," Center for Biologics Evaluation and Research Director Dr. Peter Marks said in a town hall hosted by the Covid-19 Vaccine Education and Equity Project.
According to the US Centers for Disease Control and Prevention, 645 children have died from Covid-19 in the US.
"No parent should have to lose their child to a vaccine-preventable illness if we have a vaccine that can be deployed that is safe and effective. And we will only allow something to be authorized that we find to be safe and effective," Marks said.
Children under 18 make up 22% of the US population but account for 27% of all cases nationwide, according to data published Monday by the American Academy of Pediatrics, and new infections among children remain "exceptionally high," the organization said.
And although those cases are less likely to be severe or result in death, children can end up with long-term symptoms.
"I think we have underestimated the impact on children," Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said Monday. "Look at the pediatric hospitals throughout the country ... they're seeing a lot of children in the hospital with severe infection."
Children could have a vaccine by early November, health experts say
Vaccines are only available to children as young as 12. But health officials hope that will soon change.
The US Food and Drug Administration said Friday its vaccine advisers will meet October 26 to discuss data from Pfizer's vaccine trial among children 5 to 11.
There are still a few steps on the vaccine's way to authorization. The FDA vaccine advisers would have to first make a recommendation, and the FDA would vote on it.
Then, the CDC would have to sign off before children ages 5 to 11 could start getting vaccinated.
"Most of us in the public health community are expecting that we'll see approvals of vaccines for this younger age groups sometime in early November," said Dr. Megan Ranney, the Associate Dean of Strategy and Innovation for the School of Public Health at Brown University.
"Many of us, of the people who work at FDA, have young children or they have grandchildren," Marks said. "And this is clearly one of the most important issues to get done so we're not going to be wasting any time."
And once a vaccine is made available to younger children, it would be up to parents to decide, which may prove to be an obstacle.
Only around one-third -- 34% -- of parents of 5- to 11-year-olds say that they will vaccinate their child as soon as a Covid-19 vaccine becomes available for that age group, according to Kaiser Family Foundation Vaccine Monitor results published Thursday.
Preteens and teens still have the lowest Covid-19 vaccination rates of any age group, according to the CDC. The Dean of Tropical Medicine at Baylor College of Medicine Dr. Peter Hotez told CNN's Wolf Blitzer that in the South, only about a third of 12 to 17-year-old have been vaccinated.
"We have a lot of education to do around these mRNA vaccines," Hotez said.
Infection rates nationwide are declining
After weeks of a troubling Covid-19 surge across the US, infection rates are finally on the decline -- but experts say there's still work to be done before the tide can be turned, especially when cases remain exceptionally high among children.
"I am worried that we still have some tough days ahead," said Dr. Ashish Jha, the Dean at Brown University School of Public Health. "Even though we're doing reasonably well on vaccines, we've got to do much better because the Delta variant is very good at finding people who are unvaccinated and infecting them."
On average, about 105,054 people are reported to have new Covid-19 infections every day, according to data from Johns Hopkins University. That number is about 12,000 less than the average from a week before, and experts are questioning if that decline is an ebb and flow of cases or the beginning of an end to high case counts.
"What's going to determine whether this is the end of this surge or not really is up to us," Ranney said.
What's needed is for more people to get vaccinated as well as to wear masks indoors in high-spread areas and get children vaccinated, she said.
Fauci has said the vast majority of the US will need to be vaccinated to control the spread, but according to data from the US Centers for Disease Control and Prevention only 56% of the population is fully vaccinated.
Hotez said he is still concerned about the rest of the year. The colder months bring conditions that facilitate the spread of the virus, and the US is still under-vaccinated, he said.
"We're still in for a pretty rough ride for the rest of the year," Hotez said.
A promising new antiviral
An antiviral drug promises to reduce impacts of the infection, but experts warn that it is not a replacement for vaccines.
On Friday, the pharmaceutical company Merck said molnupiravir, an investigational antiviral drug made by Merck and Ridgeback Biotherapeutics, can reduce the risk of hospitalization or death from Covid-19 by half.
But full data from the molnupiravir trial had not yet been released or peer-reviewed. And it's not clear if or when the pill might be authorized by the FDA to fight Covid-19.
"This pill is terrific and, as an ER doctor, I cannot wait to have this as another tool in my toolbox to give to patients who are sick with Covid-19," Ranney said. "But better than taking a pill is not getting sick in the first place which means getting vaccinated."
CORRECTION: A previous version of this story did not include the most complete average daily case count. The current average is 105,054 cases a day as of Tuesday morning.
CNN's Jen Christensen, Holly Yan, Susannah Cullinane, Ben Tinker, Jacqueline Howard, Mallory Simon and Theresa Waldrop contributed to this report.