Possible black box label marks major policy shift
The US Food and Drug Administration is considering adding its strongest safety warning, known as a black box warning, to Covid vaccines, according to reports first published on Friday. If implemented, the move would represent a significant shift in federal vaccine oversight and could further affect public confidence in the shots, whose uptake has already been declining.
The plan, which has not been finalized or officially confirmed by the Department of Health and Human Services, is reportedly being driven by Dr. Vinay Prasad, the FDA’s chief medical and scientific officer and head of the Center for Biologics Evaluation and Research.
What a black box warning means
A black box warning is the most prominent safety label the FDA can require. It appears at the top of a drug’s prescribing information and is reserved for risks such as death or serious injury that must be carefully weighed against a product’s benefits. Similar warnings are used on opioids to highlight dangers including addiction, overdose and fatal outcomes.
At this stage, it remains unclear whether such a warning would apply to all Covid vaccines or only certain products or age groups.
Uncertainty around scope and justification
HHS has not confirmed any decision. In a statement, spokesperson Andrew Nixon said that unless the FDA makes an official announcement, reports about the move remain speculative.
It is also unknown whether the warning would target only mRNA vaccines from Pfizer and Moderna, which have previously been criticized by HHS Secretary Robert F. Kennedy Jr., or if it would also apply to Novavax’s protein based Covid vaccine.
Safety concerns and expert response
In an internal memo last month, Prasad attempted to associate 10 deaths in children with Covid vaccines without presenting evidence. He also highlighted myocarditis, a rare side effect previously linked to early dosing schedules of mRNA vaccines, primarily in younger males.
Health authorities worldwide, including the Centers for Disease Control and Prevention, have consistently stated that the benefits of Covid vaccination far outweigh the risks. They note that myocarditis cases linked to vaccines have declined sharply and that Covid infection itself carries a higher risk of heart complications.
Vaccine makers defend safety record
Pfizer reiterated that its Covid vaccine has demonstrated strong protection against severe disease across variants, contributing to more than 14 million lives saved globally in its first year of use alone.
Moderna said the safety of its vaccine continues to be closely monitored by regulators in more than 90 countries. With over one billion doses distributed worldwide, the company said no new or undisclosed safety concerns have been identified in children or pregnant women.
Declining vaccination rates add context
The debate comes as Covid vaccination rates continue to fall. Data cited by the National Foundation for Infectious Diseases show a 27 percent drop in vaccinations from retail pharmacies since 2024, raising concerns among public health experts about long-term protection against severe disease.
