The Roles of Active and Passive Containers for Transporting Vaccines
The role of active and passive containers for transporting vaccines is to keep heat-sensitive vaccines and other essential drugs at the right temperature. However, it is difficult in some areas with limited electrical power. While there is a high demand for vaccine roll out and mass vaccination, there is also a demand for cold supply containers that will help in maintaining the potency of vaccines from the transportation and distribution to the vaccination process.
The pressure to deliver COVID-19 vaccine requires the supply chain to share resources to other products that also demand cold chain transit, including flu vaccines, cancer treatments, and genomics and precision medicine.
Veerina conjectured that the industry will make an unrivaled collaboration to communicate and disseminate information on, for instance, new faculties for tracking devices such as pallets along with data on controlled temperature transport and storage assets.
Few medical facilities have space to accommodate large numbers of vaccines at constant ultra cold temperatures. That’s why Pfizer, a leading developer in the pursuit to bring a COVID-19 vaccine to the broader market, plumped for Corning’s Valor Glass packaging back in May 2020 to ensure durability and counter breakage, damage, and intercept contamination.
Each vaccine developer has identified the roles of active and passive containers in their cold chain equipment to ensure no defects or any ineffective results of the vaccines when used.
What is Cold Chain Equipment?
Cold chain equipment (CCE) is used for storing, transporting, and distributing vaccines and can be categorized by the roles of Active Containers’ Refrigeration systems and Passive Containers’ passive cooling devices.
- Active systems include mains refrigerators and off-grid refrigerators. Mains refrigerators are cooled by compressors that increase pressure to the gas refrigerant. While off-grid refrigerators include two main subsets: the absorption refrigerator system is a heat-activated thermal cycle; it exchanges the thermal energy with its surroundings. It operates often at a lower pressure than the atmospheric pressure where this pressure is regulated by the vapor pressure of the working fluid such as petroleum gas or kerosene. Conversely, solar-powered refrigerators use electric compressors that may be driven either from batteries that have stored the power generated by solar panels, or directly from the solar panels themselves.
- Passive cooling devices include cold boxes and vaccine carriers. Cold boxes are larger devices with 6–25 L capacity, generally transported by motor vehicles, while vaccine carriers are smaller (0.5–3.5 L capacity), and generally carried by hand. They are called passive because there is no active refrigeration mechanism—the cooling is provided by coolant packs containing phase change material. Traditionally frozen plain water. To avoid freeze damage to vaccines in conventional passive cooling devices, an extra step of ‘conditioning’ is required, depending on the operational conditions, coolant-packs can be frozen, conditioned, cooled, or warmed before the actual use to maintain temperatures within the container for the entire transport and distribution period of vaccines.
The Roles of Active Deep Freezing Containers
Germany’s MECOTEC has unveiled a prototype that implements active deep freeze technology to guarantee safe and controlled temperature transport and storage that do not require dry ice for cooling. This mobile hybrid container can store and transport up to 1,000,000 vaccination doses in a standard-sized container at temperatures down to –80°C/–112°F.
“Our many years of experience in the field of cooling technology made it possible within a very short timeframe to develop the transport, storage and distribution container,” explains Jan Hüneburg, Managing Director at COOLANT, the industrial division of MECOTEC.
“We are pleased that today we can present our Mobile Hybrid Container Solution for the transport and storage of COVID-19-Vaccines globally,” states the CEO of MECOTEC Group Enrico Klauer. “Since our system is based on an active deep-freezing technology, it does not require dry ice for cooling which makes it also suitable for safe carriage by air.”
The vaccines can be carried in small or large amounts directly to the distribution station or warehouses. The vaccine veils are stored in the mobile refrigerated container in transport packaging and insulation boxes and then are transported to the vaccination center while maintaining the deep-freezing temperatures down to –80°C/–112°F.
The hybrid container design also features systems such as remote monitoring, GPS location, and complete temperature recording with temperature-sensitive alarms if any fluctuation occurs. Furthermore, independent power supply and redundancy ensure that almost 100% cooling is achieved.
Container supplies are among the rampant challenges faced by companies that are part of a large, global network planning to quickly transport and distribute huge numbers of COVID-19 vaccines to affected areas. And each link in the proverbial chain — from finding well-sustained storage to keep doses sufficiently cold to protecting them from heists — is equally important to ensure enough vaccines reach even far-flung areas as swiftly as possible.
“This is high noon for vaccination,” says Joachim Kuhn, chief executive officer of Va-Q-Tec, which rents containers and sells containers for shipping pharmaceuticals and vaccines.
The particularly designed containers vary in size but typically can hold thousands of doses of vaccines that must be kept at specific temperatures to remain potent over time.
“Everything depends on how many vaccines will be on the market, whether they require one shot or two shots, where they are produced, and how much distribution is needed. And there will be high demand for safe transports,” he explained. “So there are many, many questions. Everybody has to think about how to handle this sensitive and precious cargo.”
The Roles of Passive Containers for Vaccine Transport
A passive container system controls the heat flow through the container walls so that vaccines remain within the standard storage temperature range to prevent any damage from temperature extremes. This temperature range, including permissible temperature expeditions, must be well-maintained from the moment the vaccine load is packed until it is discharged at the end of the journey, even when the ambient temperature fluctuates widely.
Unfavorable instances most often come to light when coolant-packs are used inappropriately, the wrong type of container is chosen for the conditions of the intended journey or the journey takes longer than anticipated. Failure to manage these risks according to WHO Vaccine Management Handbook can result in:
- exposure of freeze-sensitive vaccines to sub-zero temperatures, causing loss of potency (if alum-containing vaccines are frozen, they lose their potency and must be discarded);
- exposure of heat-sensitive vaccines to temperatures above +8°C for extended periods, causing loss of potency; and
- increased risk of microbial growth in opened vials of vaccine, which can occur if reconstituted preservative-free vaccines or opened vials of liquid vaccines that do not contain preservative are exposed to temperatures above +8°C during immunization sessions.
The World Health Organization (WHO) strongly recommends that a country’s transport strategy should be validated by carrying out systematic transport route profiling exercises; these exercises should cover a representative sample of the transport routes in the country. Optimum use of the equipment and the ensuring of vaccine safety can only be achieved if transport route validation has been carried out.
The strategy must be designed to suit local conditions. The following tasks need to be completed and documented:
- determine the heat and freeze sensitivity of every vaccine being transported. Awareness of the vaccine types can greatly help in putting the vaccines at risk.
- identify the existing risks to which vaccines are currently exposed during transport.
- determine transport durations and distances, geographical and natural hazards, and other risks along all intended routes.
- determine day-night and seasonal temperature extremes along each route.
- agree on the transport modes and vehicle types that are to be used on each route.
- define a policy for labeling passive containers (e.g. content, storage and transport conditions, and destination).
- record the published storage capacities of the passive containers currently used, and their laboratory-tested performance (cold life, cool life, and, if relevant, warm life).
- establish whether current passive containers are fit for purpose and define a policy for future procurement and/or replacement of this equipment.
- evaluate the risks and benefits associated with the four different types of water-packs (frozen, conditioned, cool and warm) in the local context.
There is no single recipe for transporting vaccines safely in containers. Every method can be risky, and these risks are essential to be identified, acknowledged, understood, and well-managed in every operational context. Some strategies may work well for short urban deliveries but may not be suitable for long-distance transport to remote rural locations. There must clearer guide for the roles of active and passive containers for the transportation of the vaccines to reduce the risks of vaccine damage.
Systematic management and effective training are essential things to consider to further reduce these risks. Vaccine distribution is logistically challenging and must be carried out with thorough planning and management.
A well-managed program “can help save on program costs in ensuring program implementation efficiently without sacrificing the quality of service delivery. Poorly managed logistics systems can lead to high and/or unnecessary vaccine wastage rates, stock-outs, or improper management of waste, resulting in significant operational program costs, as well as a negative impact on public health,” World Health Organization says.