Vaccines and Preventable Diseases:
Varicella Vaccine - Storage and Handling Q&A
Clinical Questions and Answers
How should the vaccine be stored?
Both the single antigen varicella vaccine (Varivax®) and the quadrivalent combination vaccine (ProQuad®) must be kept frozen at an average temperature of 5°F (-15°C) or colder. The vaccine should also be kept away from light at all times. Proper storage is important because varicella-containing vaccine may lose potency if stored improperly. Stand-alone freezers or combination refrigerator/freezer units with separate sealed freezer doors that maintain an average temperature of 5°F (-15°C) or colder are acceptable for storing varicella-containing vaccine. Small single-door refrigerators with separate ice compartments (e.g., dormitory-style refrigerators) should not be used. Freezers in these units are less likely to maintain adequate temperatures for storing vaccine. The diluent should be kept separately in the refrigerator or at room temperature.
We strongly suggest that the freezer temperature be carefully checked prior to ordering vaccine. For new freezer units, the temperature should be monitored for at least 1 week prior to storing the vaccine. For all freezers, the temperature should be monitored at least twice each day, once in the morning when the door is first opened and at the end of day when the door is closed for the last time, to ensure that the temperature is kept at
5°F(-15°C) or colder. We recommend that a calibrated and certified thermometer be used to monitor freezer temperatures. Placing cold packs in the freezer may help stabilize the temperature and minimize temperature fluctuations during the opening and closing of the freezer doors.
What if varicella vaccine is inadvertently placed in the refrigerator instead of the freezer?
Do not administer the vaccine until you have consulted with Merck. The expiration date of the vaccine will be affected. The mishandled vaccine should be clearly marked and should be immediately placed in the freezer, separate from vaccine that has been properly handled. Call the Merck Vaccine Customer Service at 1-800-MERCK90.
What should be done with varicella vaccine in case of a power outage?
If varicella vaccine is thawed for any reason, including a power failure, you must consult the manufacturer for advice before using the vaccine. Call the Merck Vaccine Customer Service at 1-800-MERCK90.
Try to estimate the highest temperature that the vaccine was exposed to and the length of time that the vaccine was at that temperature. The recommendations from Merck will be based on the amount of time that the vaccine was exposed to temperatures higher than 5°F(-15°C). To help maintain vaccines at cold temperatures during power failures, we recommend that you always keep extra ice or cold packs in the freezer compartment. In addition, providers should have an emergency vaccine storage plan in the event of a power outage or natural disaster.
How can varicella vaccine be safely transported to off-site clinics?
Single-antigen varicella (Varivax®) and combination MMRV (ProQuad®) vaccines have similar but not identical distribution, handling, and storage requirements. Varivax® can be transported with regular ice or ice packs if the vaccine will be used within 72 hours and a good assessment can be made as to the number of doses that will be needed. However, unused Varivax® must be discarded after 72 hours at refrigerator temperatures (36°F-46°F [2°C-8°C]). If transport and use will exceed 72 hours, it will be necessary to transfer the vaccine in a high-quality ice chest with dry ice. Unlike Varivax®, ProQuad® MUST be transported at all times in temperatures 5°F(-15°C) or colder and therefore must be transported only with dry ice. Temperature must be monitored carefully to ensure that adequate temperature has been maintained. Note: Diluent should not be transported on dry ice.
Does Merck replace your vaccine if you mishandle it?
No. If the vaccine is damaged as a result of mishandling after it was received, Merck will not replace it. Merck will only replace vaccine that has been improperly shipped (no dry ice in the box), damaged or destroyed during shipping to your clinic, or damaged because of natural disasters.
Return to main Varicella Vaccination page
Content last reviewed on May 18, 2007
Content Source: National Center for Immunization and Respiratory Diseases