Florida Gov. Ron DeSantis took yet another shot at the CDC and FDA on Wednesday, claiming in a warning to his constituents that the federal agencies are trying to use them “as guinea pigs” to test new coronavirus booster shots. The break in guidance from medical professionals is nothing new for DeSantis, who has long railed against the CDC and vaccine makers—despite receiving the jab himself. On Tuesday, a CDC panel green-lit an updated COVID-19 vaccine following a recent spike in coronavirus-related hospitalizations this month. The vaccine was also approved by the FDA. DeSantis, who’s running a fledgling campaign for the presidency, called the newest vaccines “hastily-approved” boosters that “have not been proven to be safe or effective.” The CDC says otherwise, asserting they’re rigorously studied before approval.