Effective vaccine storage and handling is an important component of proper vaccine management. Several recent scientific studies on equipment used for vaccine storage, as well as an improved understanding of best practices, have prompted the Centers for Disease Control and Prevention (CDC) to provide updated guidance on proper vaccine storage and handling practices.
See the CDC’s November 2012 Vaccine Storage & Handling Toolkit at:
Use the correct equipment to properly protect vaccine integrity. To ensure that refrigerators and freezers are maintaining the appropriate temperatures for vaccine storage, each unit should have a calibrated thermometer. Read and document temperatures on each unit a minimum of twice daily, including recording the minimum and maximum temperatures once each day. The temperature data, whether it is electronic or paper, must be retrievable for at least three years.
Biosafe glycol-encased probes are preferred, as they more accurately replicate the actual vaccine temperature in vials and therefore give more accurate temperature readings. The CDC recommends:
Ensure you have a back-up temperature probe for each vaccine storage unit. The back-up probe should match the primary set up (ie, temperature probe in glycol). Establish a different calibration schedule for the back-up probe so that it is available when the primary probe is sent for calibration. The CDC does not recommend fluid-filled biosafe liquid thermometers, bi-metal stem thermometers, food thermometers, household mercury thermometers, chart recorders, infrared thermometers, and non-calibrated thermometers for vaccine monitoring.
Use digital data loggers with detachable, programmable probes for 24-hour monitoring. If a storage unit is operating outside the recommended temperature range (see Sidebar), digital data loggers with detachable, programmable probes provide information about the length of time the unit has been out of range. Simple minimum/maximum thermometers provide only the warmest and coldest temperatures reached during a 24-hour period. Additionally, many digital data logger thermometers have special software that allows users to set the frequency of the temperature readings, download data from the device, and calculate temperature averages, minimums, and maximums. In the event of a temperature excursion, this detailed and precise information allows vaccine manufacturers to make specific recommendations about the viability of vaccine exposed to temperatures outside recommended ranges.
Store vaccines in stand-alone refrigerators/freezers, as these units provide a more stable temperature environment than a combination unit. The National Institute of Standards and Technology (NIST) tested household combination refrigerator/freezers and found the freezer section of these units was incapable of maintaining the correct frozen vaccine storage temperatures consistently, especially during defrost cycles. In addition, avoid using dormitory-style refrigerators as they have great fluctuations in temperature, providing a less stable environment compared with full-size refrigeration units. Where possible, CDC recommends pharmaceutical grade or purpose-built refrigerators/freezers.
Place vaccines in the proper location within the refrigeration unit. Vaccines should be placed approximately two to three inches from the walls and stored in bins by vaccine. Because most vaccines are light sensitive, they should remain in their boxes within the bins until used. Vaccines should never be stored in door compartments or in the crisper areas of refrigerators. In fact, should non–commercial grade units be used, the CDC recommends removing the crisper drawers and storing water bottles in both the crisper area and the door compartments to help maintain consistent temperature. In addition, do not store vaccines directly under any air vents, and ensure that air vents are never blocked.
Temperature Excursion Checklist*
1. Checklist for general power loss
2. Checklist for presumed storage unit malfunction Disposition of Storage Unit If unit is too warm, too cold, too noisy, or stopped, check the following items:
3. Disposition of vaccine (if power not restored or if temperature does not begin to recover)
*Centers for Disease Control and Prevention Web site. http://www.cdc.gov/vaccines/recs/storage/toolkit/default.htm Accessed December 19, 2012.
Jennifer Karpinski is a senior editor at Pharmacy Purchasing & Products magazine. PP&P would like to thank the CDC for their assistance with this article.