KEY POINTS
  • Doses of Pfizer's vaccine were quarantined in California and Alabama after an "anomaly" in the transportation process caused the storage temperature to get too cold.
  • Army Gen. Gustave Perna, who oversees logistics for Operation Warp Speed, said the doses "never left the truck."
  • Pfizer's vaccine, which was developed with German drugmaker BioNTech, requires a storage temperature of around minus 70 degrees Celsius.

U.S. officials said Wednesday they quarantined several thousand doses of Pfizer's coronavirus vaccine in California and Alabama this week after an "anomaly" in the transportation process caused the storage temperature to get too cold.

Pfizer's vaccine, which was developed with German drugmaker BioNTech, requires a storage temperature of around minus 70 degrees Celsius. Vials of the vaccine are stored in trays, which carry a minimum of 975 doses each, according to the Centers for Disease Control and Prevention.