Vaccines, as we are all being strongly reminded, protect patients from disease. Proper storage of these sensitive assets ensures they achieve that goal. Vaccine storage was a critical element in healthcare long before the pandemic arrived. The Centers for Disease Control and Prevention (CDC) have guidelines in place that outline how vaccines should be handled and stored. In this article, we will review those guidelines and how they ensure the vaccine integrity.
Why Vaccine Storage Is So Crucial
Aside from potential spoilage, there is a far greater risk from improper vaccine storage. Patients lose confidence in the entire vaccination program and tend to shy away from receiving vaccines. This can have a huge impact on the spread and ability to control of any virus or disease. Individuals who may have received a compromised vaccine will require revaccination. For many patients, this is a stressful event. Of course, this is accompanied by the significant financial loss from vaccines that are not properly stored or handled. The vaccine cold chain must be maintained at all times to prevent any loss. The cold chain encompasses the environment surrounding the vaccine from the moment it is manufactured through the transport and storage of the vaccine to administration of the vaccine to a patient. The most effective way to prevent any complications during the cold chain is through vaccine temperature monitoring.
CDC Guidelines By Category
Here is a breakdown of the recommendations made by the CDC concerning various parts of the vaccine cold chain:
Many types of vaccine storage units are available. The CDC recognizes purpose-built and household-grade units but recommends the use of either purpose-built or pharmaceutical-grade units that can both refrigerate and freeze. Purpose-built units are specifically designed for vaccines. The size of the unit is dependent on the facility and available space. Acceptable units include compact, under-the-counter, and large sizes. Although household-grade units are acceptable alternatives, the CDC does not recommend using the freezer compartment in these units because they are not typically adequate for proper vaccine storage.
Storage Unit Placement
Storage units require good air circulation; placement in a well-ventilated area is ideal. There should be space between the unit and any solid obstacle including walls and the ceiling. Nothing should block the motor compartment and the storage unit should sit on a firm, level surface above the floor. Storage units best operate when in rooms that maintain a constant temperature ranging between 20C and 25C.
Storage Unit Doors
Storage unit doors must close properly and remain closed at all times when vaccines are not being retrieved from them. When a door is left open it affects the internal temperature of the storage unit. It can also expose vaccines to light, which can negatively affect some vaccines. The CDC suggests these tools to aid in ensuring that storage unit doors remain closed: self-closing hinges, door locks, and door alarms.
The CDC is very specific on the acceptable temperature ranges for storing vaccines. Refrigerators should hold temperatures between 2C (36F) and 8C (46F). Freezers must maintain temperatures between -50C (-58F) and -15C (+5F). The thermostats of each storage unit must be set at either the factory-set or midpoint temperature and the use of temperature monitoring devices is recommended to ensure accurate temperature levels.
Temperature Monitoring Devices (TMDs)
A TMD must be included in each vaccine storage unit. The CDC recommends a Digital Data Logger (DDL) for this purpose. A DDL is a portable, battery-operated device that tracks temperature by taking readings with either an internal sensor or an external probe. The data collected is stored in a memory and provides an accurate history of temperatures recorded over a set period. The CDC TMD guidelines indicate that each transport unit must contain a DDL and that a backup DDL should be available in case of malfunction by or damage to the original data logger.
Vaccine Temperature Monitoring Equipment
The CDC further recommends twice daily monitoring of both vaccine storage equipment and the temperatures within them. This is to quickly identify temperature excursions so they can be acted upon as soon as possible. Although several different types of TMDs are available in the marketplace, only certain ones are adequate for the task of monitoring vaccine temperatures. The CDC urges users to avoid the following types of TMDs because they are not capable of detecting temperature excursions: alcohol or mercury thermometers, liquid vail bimetal stem TMDs, food temperature TMDs, chart recorders, infrared TMDs, or TMDs that do not have a valid or current Certificate of Calibration.
Responding To Temperature Changes
A temperature excursion requires immediate attention. In the event of a temperature excursion the process to enact, as approved by the CDC, is as follows:
– Anyone alerted to a temperature excursion must notify the designated supervisor of the event
– Exposed vaccines must be placed in a separate container and labeled “DO NOT USE” to notify others
– The vaccine coordinator or supervisor should begin to document all relevant information related to the event and action taken.
Vaccine Storage Unit Maintenance and Troubleshooting
Both storage units and TMDs require regular maintenance. Vaccine storage units must be inspected and any problem immediately rectified. This includes checking the seals and door hinges, cleaning coils and other components, defrosting manual-defrost freezers, cleaning interiors, and a quarterly test of the backup generator.
Vaccines are valuable. They are essential to the prevention of disease and have a financial cost related to their manufacture, transport, and storage. The cold chain that ensures vaccines are in pristine shape when they are administered requires careful attention. The main focus of that attention is temperature-related. The CDC has set out guidelines on handling and storing vaccines throughout the cold chain. These guidelines ensure vaccines do not spoil and are in their best condition when given to a patient.