The COVID vaccine must be kept at a very specific temperature in order to be effective. The Pfizer vaccine must be stored between -112 and -76 degrees Fahrenheit and Moderna must be kept at -13 and 5 degrees Fahrenheit. Then the vaccine must be administered within six hours of thawing—otherwise, it’s no longer viable. If a vaccine dose is administered after improper storage, including a temperature issue, the CDC advises administrators to contact the vaccine’s manufacturer. “If the manufacturer provides information supporting that the dose should be repeated, the repeated dose may be given immediately (no minimum interval) in the opposite arm,” says the CDC. And for more up-to-date COVID news delivered straight to your inbox, sign up for our daily newsletter. On Feb. 23, a local NBC News affiliate reported that a New York State-run vaccination site on Long Island administered some COVID vaccine doses that had been stored at the wrong temperature. As a result, 81 of the 1,379 people vaccinated on Feb. 15 had to return for an additional shot. Though there were no health risks due to the original shot they were given, there’s concern about the vaccine’s efficacy if it wasn’t properly stored. And to see what you should steer clear of after your shot, check out Don’t Do This Until a Month After Your COVID Vaccine, Experts Warn. Getting a shot again is considered safe if one of the doses was compromised. “Knowing that the vaccine itself is really not an active virus, it’s just a part of a protein portion that it makes from the mRNA of the virus, I don’t think it’s necessarily dangerous that we know of to get that third dose in this case,” Frederick Davis, MD, of Northwell Long Island Jewish Hospital, told NBC News. “The hope is that if the first one wasn’t as effective because it wasn’t stored at the proper temperature that this will hopefully boost your immunity a little bit better.” And to learn about what you need to avoid right after your shot, check out The CDC Says Don’t Do This Within 2 Weeks of Your COVID Vaccine.ae0fcc31ae342fd3a1346ebb1f342fcb In its guidelines, the CDC notes a few other reasons someone may need to get the vaccine again. If you receive less than half of the authorized dose volume because some leaked out, if equipment faltered, or if you pulled away, the administrator should give you the authorized dose in the opposite arm immediately. Additionally, if the dose you receive was expired or administered with the wrong kind or amount of dilutent, you could need to get the vaccine again. And to see what you’ll finally be able to do again after getting your shot, check out Dr. Fauci Says It’s Safe for You to Do This Once You’re Vaccinated.