Vaccine Storage and Handling: Current Considerations and Trends
Failing to keep the cold chain at the required temperature costs lives.
Making an effective vaccine faces significant obstacles, but it can’t protect people without proper storage and handling, which depend on a complete line of pharmaceutical-grade refrigerators and freezers that maintain the necessary conditions to keep vaccines safe and effective. According to the U.S. Centers for Disease Control and Prevention’s Vaccine Storage and Handling Toolkit: “Proper vaccine storage and handling are important factors in preventing and eradicating many common vaccine-preventable diseases.” Nonetheless, this toolkit points out that every year “storage and handling errors result in revaccination of many patients and significant financial loss due to wasted vaccines.” Without the proper storage, a vaccine can lose potency, resulting in “inadequate immune responses in patients and poor protection against disease,” according to the CDC. This can only be prevented by storing vaccines— from the raw materials through manufacturing and delivery to patients—within the recommended range of temperatures for a particular product.
A vaccine’s temperature must be maintained accurately and consistently. These requirements apply to all stages of a vaccine’s lifecycle and impact a wide range of participants in the process, from pharmaceutical and logistics companies to storage and clinical sites. Some of the vaccines in development for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes COVID-19, create new challenges. For example, the COVID-19 vaccines under development by Moderna and BioNTech/Pfizer are based on messenger RNA (mRNA), which is very unstable, and the vaccines must be stored at –20° C or –70 to –80° C, respectively (See Covering the Temperature Range for COVID-19 Vaccines). Reporting in Science, Jon Cohen wrote that the ultra-low temperature needed to store the BioNTech/ Pfizer means that “delivering it to hundreds of millions— if not billions—of people remain huge challenges.”
Scientists see a range of challenges from mRNAbased vaccines. As an example, theoretical chemist Hannah Wayment-Steele of Stanford University and her colleagues wrote: “RNA hydrolysis presents problems in manufacturing, long-term storage, world-wide delivery, and in vivo stability of messenger RNA (mRNA)-based vaccines and therapeutics.” Several of these obstacles for COVID-19 vaccines can only be addressed with improvements in the cold chain, and those enhancements must reach around the world.
FILLING THE COLD CHAIN GAP
So, logistics and storage companies must provide enough ultra-low freezers to keep the vaccines safe. At clinical sites, personnel must be able to safely handle the frozen vaccines, thaw them, and keep them viable until use. Addressing some of these concerns will require collaborations, such as the partnership between vaccine developer COVAXX and logistics company Maersk. Plus, many countries must add cold chain equipment. For example, India’s health secretary Rakesh Bhushan, stated, “We are in a position to not only augment and strengthen but also add to our cold chain capabilities.”