BEHIND THE SCIENCE

 

Vaccines are a topic that has been at the top of everyone's mind for over a year. As a result, there has been a lot of focus worldwide on the unique storage conditions required for the new mRNA-based vaccines. Some of these new vaccines require ultra-low temperature storage at or around -80°C, while others require storage at higher temperatures, like -20°C.

 

Whether it's a new mRNA-based vaccine or a traditional vaccine, the storage conditions listed by the manufacturer typically specify that vaccines need to be stored from +2°C to +8°C just before administration and that they must be prevented from freezing to protect their viability.

 

One would think that protection from freezing is an easy task for a refrigerator. Yet, given that the temperature storage requirements are so close to freezing, any issues with the refrigerator’s temperature control or anything that can obstruct airflow, such as overloading with too much inventory, can put products at risk. In fact, a DHHS Inspector General report from 2012 stated that the vast majority of clinical providers they studied allowed vaccines to be exposed to improper temperatures, which can affect potency and efficacy, exposing vaccine recipients to unnecessary risk.

 

To help combat inappropriate storage conditions, the CDC worked with the National Science Foundation (NSF) International and the American National Standards Institute (ANSI) to create a committee to develop guidelines for vaccine refrigerators and freezers. The committee comprised industry experts from vaccine manufacturers, pediatricians, state health authorities, refrigeration manufacturers and other interested parties, who worked over the last six years to create new standards. The committee needed to tackle several challenges. Those challenges included overcoming the presence of automatic defrost cycles in many freezers that can put vaccines out of their recommended storage conditions and refrigerators that cannot maintain tight temperature tolerances or can drop into freezing conditions due to differences in load or environmental conditions.

 

The committee released the new guidelines in June of 2021. This new standard will help ensure that refrigerators and freezers certified to this standard and used for vaccine storage are designed and built to help preserve the efficacy of the vaccines being stored in them.

 

As you select vaccine storage equipment, consider carefully what your requirements are for both frozen and refrigerated storage, the available space in your facility, and most importantly, the equipment design. Selecting equipment that is purpose-designed from the ground up with cold wall freezer sections to eliminate temperature spikes caused by freezer defrost cycles and refrigerators that maintain even temperature uniformity regardless of the product load while protecting products from freezing is critical.