Local Authorities Relying on Dry Ice for COVID-19 Vaccine Release Will Struggle to Effectively Manage Multiple Doses

Dry ice is an incredible scientific material. In solid form, it can be used to rapidly freeze liquid-based materials and keep them frozen at ultra-low temperatures (ULT), for an extended period of time. Because dry ice is made of carbon dioxide, it is an environmentally friendly way to manage the byproducts of petroleum production, it is easy to manufacture, and has been used for decades. Today, dry ice is frequently used in the transportation and distribution of perishable goods and even gets used in scientific laboratories to flash-freeze biological samples.

60 Minutes on CBS Nightly News recently covered a story on Operation Warp Speed investigating how Army General Gus Perna is preparing to inoculate 300 million Americans over the next few months. In the interview, General Perna expressed that he is most concerned about multi-dose vaccine requirements. It was described in this segment that Pfizer will be using dry-ice to support distribution of their vaccines, but how will these local clinics manage, store and guarantee effective administration of multiple doses of these vaccines? Is dry ice a great solution for local storage and administration? Probably not.

Dry ice while inexpensive, ultra-cold, and environmentally neutral, does unfortunately pose some serious health and handling risks. The Occupation Safety and Health Administration (OSHA) summarizes proper dry ice handling and management in this QuickFacts for Laboratory Safety (using) Cryogens and Dry Ice.

General Precautions When Working with Dry Ice:

  • Avoid eye or skin contact with these substances.
  • Never handle dry ice or LN2 with bare hands. Use cryogenic gloves, designed specifically for working in freezers below -80°C and for handling containers or vials stored in these freezers.
  • Always use appropriate eye protection.
  • Do not use or store dry ice or LN2 in confined areas, walk-in refrigerators, environmental chambers, rooms, or vehicles without ventilation. A leak in such an area could cause an oxygen-deficient atmosphere.
  • Never place on tile or laminated counters because the adhesive will be destroyed.
  • Never store a cryogen in a sealed, airtight container at a temperature above the boiling point of the cryogen; the pressure resulting from the production of gaseous carbon dioxide or nitrogen may lead to an explosion.

So why were we able to experiment with these materials in our elementary-school science labs if they were this dangerous? The answer comes down to the amount of dry ice exposure. In small batches, with the correct PPE, dry ice is safe. If being used in larger volumes, for frozen storage – it must be replenished regularly to maintain ultra-low temperatures. Having replenishment stock on hand while working in small clinical rooms that were not designed for dry ice, could be very dangerous.

Dry ice sublimates at room temperature – using oxygen to emit CO2 into the atmosphere. Storage in a small room without ventilation, like you would see in a clinic or pharmacy, could lead to potential asphyxiation. Dry ice is so cold it can cause serious skin burns if the correct gloves are not used, and goggles and/or face shields must be worn to prevent any contact with the eyes.

With dry ice demand steadily increasing over the years, and less transportation vehicles on the roads due to COVID-19 lockdowns, dry ice manufacturers are reporting their material supply has decreased by almost 30%, causing an international shortage. This shortage will only intensify as the entire world tackles a herculean effort like COVID-19 vaccine release.

The last and final point that needs to be made about using dry ice for ultra-low temperature storage is that it is not a permanent solution or an exact science. Dry ice itself stays at -78°C, but whether it keeps the products thermally protected at that exact temperature while it sublimates, is not confirmed.

With advancements in cell and gene research and new regenerative medicines coming to market every day, ULT storage needs are most likely not going anywhere. And the manufacturers of these mRNA vaccines are still not sure how many doses will be required or even if this will turn into an annual vaccination like the flu shot.

Investing in non-consumable ULT storage infrastructure now will serve many healthcare operations well for the foreseeable future. Whether with a large, upright ULT freezer or a portable cooler-style freezer appliance, the need will remain. The table below summarizes how Stirling’s ultra-lightweight, portable ULT25NEU stands up to a dry-ice solution for ULT storage.

For more information on how Stirling Ultracold products are supporting COVID-19 vaccine efforts, our COVID-19 response page is regularly updated with the latest updates.

Local Planning Efforts for COVID-19 Vaccine Distribution

In our last blog post, we pointed out some of the daunting challenges associated with “Operation Warp Speed” (OWS) because certain COVID-19 vaccine candidates will require storage at -80°C, while other doses may need to be frozen from -40°C to -20°C. Perhaps the most significant OWS obstacle now falls to local/regional COVID preparedness teams to plan for vaccine “last mile” distribution and administration. “Last mile” is a general term used within the cold chain space to indicate the connection from a regional repository to the end patient recipient. The responsibility sits with thousands of local health systems, clinical sites and pharmacies to plan local vaccine inoculation, where the side task of now needing to maintain the ultra-low temperature (ULT) cold chain may be the most difficult aspect of guaranteeing safe and effective doses. That is because most local facilities, processes and organizations providing vaccines for patients around the world have never had to prepare for a task of this magnitude, let alone at this temperature range!

Last Mile Vaccine Cold Storage Challenges
This lack of local preparedness is evidenced by the recent list of questions submitted by the National Governors Association to the Trump administration, which focuses on pressing issues related COVID-19 vaccine distribution, administration and cold chain at the regional and municipal level. This letter expresses specific concerns about dry ice shortages and handling issues, as well as the limited availability of ULT storage equipment in health care systems. In fact, health care facilities and pharmacies that will need to store and administer COVID-19 vaccines rarely have access to ULT freezers. Traditional ULTs have tended to be too expensive, bulky and noisy for clinical environments, with most requiring dedicated power supply to remain operative.

Local leaders will also be challenged to get vaccines from central state repositories to remote or immobile communities, such as rural populations, extended care facilities, nursing homes, etc., without breaking the ULT cold chain. Vaccine distribution partnerships with large pharmacy chains or health systems will only work if patients can and will drive to them. Finally, large pharmacy chains are not consistently available across all geographies and one size may not fit all.

Cold Storage Solutions for Local COVID Preparedness
To maintain vaccine efficacy, health care facilities and pharmacies have the option of deploying ULT freezers designed for remote and portable use in limited spaces. Stirling Ultracold’s ULT25NEU portable freezer and SU105UE undercounter model are ideal for local vaccine administrators who will suddenly find themselves needing remote and on-site ultra-low storage of frozen vaccine doses. These compact, lightweight units deliver the same performance and reliability as full-size ULTs and can be easily moved throughout clinical sites and plugged into any outlet worldwide, avoiding the need for building rewiring or HVAC modifications.

Depending on which vaccine candidates release, cold storage requirements of -20°C to -80°C must be available, and Stirling Ultracold freezers are the ONLY units available to cover that range and will help local leaders cover their bases.

Stirling ULT freezers are also available with SenseAnywhere remote cloud-based monitoring for these critical vaccine doses. With precise temperature setpoint control and the ability to log vaccine temperatures, point-of-care facilities and pharmacies can also maintain a reliable audit trail on site.

With the limited availability, life span and temperature control of dry ice cooling, portable and compact ULT storage will become a critical linchpin for local delivery of safe and effective vaccines to the public.

A Local Health System Leading the Way
The North Dakota Department of Health recently took notice of the unique temperature range and compact ULT models offered by Stirling Ultracold as they finalized their COVID preparedness programs. They’ve since decided to purchase multiple ULT25NEU portable freezers to distribute these vaccines from their central warehouses within their population. The ULT25NEU portable units are capable of transporting smaller batches of vaccines to local clinics and storing them for multi-dose waves. All the while, these ULT freezers hold doses at optimal temperatures until the vaccine is ready to be administered. With this last mile solution, North Dakota DOH now has the potential to become the model for many other more-remote communities across the United States.

Learn how to lead the way in COVID preparedness for your area. Download our COVID-19 Vaccine Administration Local Planning Guide