In what has become a pattern of spreading vaccine misinformation, the Florida health department is telling older Floridians and others at highest risk from covid-19 to avoid most booster shots, saying they are potentially dangerous.

Clinicians and scientists denounced the message as politically fueled scaremongering that also weakens efforts to protect against diseases like measles and whooping cough.

A prominent Florida doctor expressed dismay that medical leaders in the state, leery of angering Gov. Ron DeSantis, have been slow to counter anti-vaccine messages from Surgeon General Joseph Ladapo, including the latest covid bulletin. Ladapo is a DeSantis appointee and the top official at the state health department.

The bulletin makes a number of false or unproven claims about the efficacy and safety of mRNA-based covid vaccines by Pfizer and Moderna, including that they could threaten “the integrity of the human genome.” Florida’s guidance generally regurgitates ideas from anti-vaccine websites, said John Moore, a professor of microbiology at Weill Cornell Medicine.