One of the most advanced US coronavirus vaccines, created by Pfizer in partnership with BioNTech, has to be stored at -70° Celsius (-94° Fahrenheit), or around 30°C colder than the North Pole in winter. It’s far from certain that the vaccine will be approved for widespread distribution. But if it is, very few freezers go that cold.
“There’s no precedent for vaccines to be stored at that low of a temperature,” says Soumi Saha, a pharmacist and director of advocacy at Premier, which arranges healthcare purchases for hospitals, nursing homes, and other providers. Most vaccines are transported along the cold chain network at 2° to 8°C (35° to 46°F), with the odd vaccine requiring temperatures as low as -25°C (-13°F.)
Those few US freezers that can reach -70°C are typically lab freezers, says Saha, which have completely different regulatory requirements from pharmaceutical freezers.