Robert F. Kennedy Jr. testifies Jan. 29 at his Senate hearing on his nomination to be the secretary of the Department of Health and Human Services.

WASHINGTON – President Donald Trump defended a decision by a Centers for Disease Control and Prevention advisory panel to stop recommending that newborn babies receive a first dose of the hepatitis B vaccine within 24 hours of birth.

The committee issued the controversial new guidance, which reversed decades of well-established medical advice, during a Dec. 5 meeting. The remarkable policy change immediately prompted backlash from public health experts, who worried it could undo decades of declines in new infections from the liver-damaging virus since all newborns began receiving the shot.

The president said in a social media post the same day that the vaccine panel made a "very good decision" to alter the schedule, which he called "ridiculous."

"I am fully confident Secretary Robert F. Kennedy, Jr., and the CDC, will get this done, quickly and correctly, for our Nation’s Children," he wrote. "Thank you, Mr. President. We're on it," the Health and Human Services secretary replied.

The Advisory Committee on Immunization Practices, whose membership was overhauled by Kennedy to add more vaccine skeptics, said babies born to mothers who have not tested positive for hepatitis B should not get the first hepatitis B vaccine until they are at least two months old.

Even some congressional Republicans are wary of that guidance. Sen. Bill Cassidy, R-Louisiana, a doctor who chairs the Senate's health committee, urged the acting CDC director not to sign the new recommendations and "instead retain the current, evidence-based approach."

The CDC's shift, he stressed, "makes America sicker."

"As a liver doctor who has treated patients with hepatitis B for decades, this change to the vaccine schedule is a mistake. The hepatitis B vaccine is safe and effective," he posted on social media. "Before the birth dose was recommended, 20,000 newborns a year were infected with hepatitis B. Now, it’s fewer than 20. Ending the recommendation for newborns makes it more likely the number of cases will begin to increase again."

Contributing: Erin Mansfield, USA TODAY

Zachary Schermele is a congressional reporter for USA TODAY. You can reach him by email at zschermele@usatoday.com. Follow him on X at @ZachSchermele and Bluesky at @zachschermele.bsky.social.

This article originally appeared on USA TODAY: Trump defends controversial new hep B vaccine guidance for babies

Reporting by Zachary Schermele, USA TODAY / USA TODAY

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