Why it matters: Trump's pick, which was confirmed after markets closed, puts one of the nation's foremost vaccine skeptics in charge of America's health care agencies.
By the numbers: The stocks of Moderna, BioNTech and Novavax fell5.6%, 7.1% and 7.0%, respectively Thursday.
All three companies get significant revenue from COVID vaccines.
Trump posted on Truth Social Thursday afternoon that HHS under Kennedy would "play a big role in helping ensure that everybody will be protected from harmful chemicals, pollutants, pesticides, pharmaceutical products, and food additives that have contributed to the overwhelming Health Crisis in this Country."