Covid-19 has brought numerous niche topics into public awareness over the past year, from virus transmission rates to face masks. Now we can also add cold chain logistics to the list – a crucial part of distributing and storing vaccines.
According to US-based ABI Research, there could be an average of 271 million doses of Covid-19 vaccines shipped each month in 2021. This means at least 850 temperature-controlled trucks will leave Pfizer and Moderna manufacturing facilities every month (the estimate was made prior to AstraZeneca approval).
“The pandemic has attracted significant attention to the pharma supply chain,” says Victor Wildhaber from the Institute of Supply Chain Management at the University of St Gallen. Together with the consultancy Logistics Advisory Experts, Wildhaber has carried out a study into the performance of air freight containers, comparing temperature regulation, CO2 profile and economic efficiency.
Temperature regulation is critical for Covid-19 vaccines. At the most extreme end of the scale is the Pfizer BioNTech vaccine, which must be stored at -70°C to keep it from spoiling. The Moderna vaccine must also be frozen, between -25°C and -15°C, while AstraZeneca’s vaccine can be refrigerated at between 2°C and 8°C.
Problems with capacity
This poses an unprecedented challenge to the global cold chain. “Even before the pandemic, the cold chain was operating close to capacity handling various temperature-controlled goods, from medicine to groceries or even artworks,” says Wildhaber. Now it must cope with the added burden of hundreds of millions of vaccine doses.
To make things worse, the reduction in commercial air traffic has actually cut capacity as passenger jets often have excess space to transport freight. And dry ice, an effective coolant for the vaccines, is classed as dangerous goods, meaning there are strict limits on how much is allowed on board an aircraft. This adds extra financial and environmental cost to vaccine transportation.
The challenges of staying cool
Coronavirus is likely to drive much-needed improvements in the quality of temperature-controlled logistics. Breaks in the cold chain, due to power failures or control checks, for example, currently lead to losses of around $34 billion each year.
The challenges are particularly high in developing regions, where hot climates, unreliable electricity supplies and a lack of transport infrastructure can make distribution and storage extremely difficult. Around 1,000 new units of the Arktek off-grid refrigerator are being manufactured specifically for Covid-19 vaccinations. The passive storage unit was developed by the Bill and Melinda Gates Foundation and can keep vaccines cold for a month or more on a single set of frozen ice blocks.
According to Victor Wildhaber’s study, the best form of cold chain storage is a new form of ‘hybrid’ container. It combines the most effective elements of active containers, cooled by battery or electricity, and passive ones. “Hybrid containers are pre-conditioned in a cold storage room and require neither a mechanical opening nor electricity connection,” says Wildhaber. “The containers insulate the inner section and depending on the surrounding temperature, they either give off or absorb heat or cold.”
The hybrid technique also represents a more environmentally sustainable option than passive containers with dry ice or single-use boxes that can quickly build up in areas with limited recycling infrastructure.
Not just for pharma?
Improvements in tracking technology are enabling further improvements. German start-up Tec4med’s NelumBox, for example, has built-in sensors that provide real-time location and status updates. A personalised access function ensures only approved users can open the box.
Tec4Med’s Elisa Blank says that while they developed the container for medical transport, they believe their cold chain technology will become increasingly relevant for other sectors. “We decided to focus first on one particular area. The thought was that if we can fulfil the rigorous demands of pharma logistics, then we can manage everything else.”