Centers for Disease Control and Prevention Director Robert Redfield told senators that he didn’t mean to imply last week that it could take into the second half of next year for enough Covid-19 vaccine to be available to inoculate all Americans.

Redfield said at a Senate health committee hearing Wednesday that about 700 million vaccine doses should be available by April, echoing a timeline laid out by Paul Mango, deputy chief of staff at the Department of Health and Human Services, last week.

The vaccine candidates that are furthest along in development will require a two-dose regimen. Redfield’s comments last week, in an appearance before a different Senate panel, were “alluding to how long I thought it would take to get those doses into the American public,” he said. It could take through July to disburse the vaccine to all Americans that want one, Redfield said.

President Donald Trump said last week that he had called Redfield after his earlier testimony to tell him his comments weren’t correct.

Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, agreed Wednesday with the timeline of 700 million doses by April.

Political Questions

The heads of U.S. health agencies attempted during the hearing Wednesday to reassure the public that staff are making decisions, particularly surrounding a vaccine, based on science, not politics. Food and Drug Administration Commissioner Stephen Hahn committed to taking any inoculation his agency authorizes.

“FDA will not authorize or approve a vaccine that we would not feel comfortable giving to our families,” Hahn said.

The agency plans to “provide additional information so that it is clear what we expect” from vaccine manufacturers that apply for emergency authorization of a shot, Hahn said. Peter Marks, director of the FDA’s biologics office that oversees vaccines, said Sept. 10 that the agency would put out guidelines for vaccine makers that will set a higher bar for emergency authorization.

Redfield said that CDC data indicates 90% of Americans are still susceptible to the virus.

Health officials also said they were dismayed at studies showing that “a disturbing number” of people who recover from Covid-19 experience inflammation in their heart muscles, Fauci said. The inflammation is “really quite puzzling,” Fauci told lawmakers, and it remains to be seen whether it will subside or whether those who have had the virus could suffer from cardiovascular issues later on.

“These are the kinds of things that tell us we must be humble,” Fauci said, “that we do not completely understand the nature of the virus.”

Childhood Cases

In another area of concern, hospitalization rates among children with Covid-19 increased during the summer, according to CDC’s prepared remarks for the hearing.

“Though the mortality rate is low for children aged 18 years and younger, Covid-19–associated hospitalization rates increased among this age group during the summer,” according to the testimony.

The CDC has previously reported that from March 1 through July 25, 1 in 3 children admitted to a hospital for Covid-19 ended up in an intensive-care unit. The number of pediatric hospitalizations is still small compared with adults, but the data do highlight that kids aren’t immune to the virus — as President Donald Trump has claimed — and can suffer serious illness.

The percentage of all hospitalizations for Covid-19 that involve children rose from 0.8% May 21 to 1.7%, totaling 5,016, the American Academy of Pediatrics reported on Sept. 17. Children represented 10.3% of the more than 5.7 million Covid-19 cases in the U.S., the academy said. When the coronavirus pandemic began earlier this year, the CDC originally said children represented 2% of Covid-19 cases.

Redfield didn’t immediately expand on the prepared remarks, but a CDC report shows that weekly hospitalizations for all ages related to Covid-19 hit a second peak the week ending July 18. Weekly adult hospitalizations fell between the weeks ending Aug. 1 and Sept. 12, while the rates among children remained steady during that time period, the CDC said.