Moderna COVID Vaccine Is Under Investigation For This Reason 01/19/21 AT 7:51 AM The California Department of Public Health has opened an investigation into one lot of a COVID vaccine from Moderna after it possibly caused several severe allergic reactions. The lot, which contained about 300,000 doses of the drug, has been recommended by California State Epidemiologist Dr. Erica S. Pan to stop being administered while it is under investigation by the state, Moderna, and the Centers for Disease Control and Prevention, and the Food and Drug Administration. The doses of the vaccine were distr...