Scientists at the University of Oxford in the UK are developing a vaccine candidate targeting the rare Bundibugyo strain of Ebola as health authorities respond to the latest outbreak in the Democratic Republic of Congo (DRC).
But while efforts are focused on containing the virus, the outbreak is also drawing renewed attention to cold-chain disruption – one of global healthcare’s most persistent logistical weaknesses.
According to the World Health Organization, around half of supplied vaccines are wasted globally due to failures in temperature-controlled storage and transport, with losses particularly acute in developing countries where vaccine access is often most limited.
The challenge became especially visible during the Covid-19 pandemic, when some vaccines required storage at temperatures between -80°C and -60°C, placing huge strain on refrigeration, cryogenic transport and medical supply chains.
In an effort to minimise losses, WHO and regional bodies pushed for ‘Internet of Things’ temperature monitoring and the adoption of thermostable vaccines that can withstand warmer temperatures.
However, losses still persist. UNEP figures suggest that failures in the cold chain results in an estimated annual loss of $34.1bn.
Even in developed countries, the supply chain is fragile. According to Open Access Government, almost five million doses of the Covid vaccine were wasted by the end of October 2021 in England alone.
The backbone of vaccine delivery
The latest Ebola response is again highlighting the role of industrial gases and cooling infrastructure in vaccine manufacturing, storage and deployment.
Nitrogen is widely used in pharmaceutical manufacturing for inert blanketing and vial filling, while dry ice and cryogenic systems help maintain ultra-low temperatures during vaccine transport and storage.
Freeze-drying, biologics manufacturing and long-term sample preservation can also rely on tightly controlled gas environments and cryogenic storage systems.
Liquid nitrogen is also used across pharmaceutical and biomedical sectors for ultra-low temperature preservation of biological materials, including vaccine samples, cell therapies and laboratory specimens.
The current outbreak has prompted WHO to declare a public health emergency of international concern following hundreds of suspected cases and more than 200 deaths.
Dry ice is an incredibly effective cooling agent for deep-frozen medical shipments (like specific vaccines, tissues, and biological samples) because it reaches an extreme temperature of -78.5°C ©Shutterstock
Researchers at Oxford hope clinical trials for the Bundibugyo vaccine candidate could begin within two to three months. There is currently no approved vaccine for the strain.
Vaccines for Ebola do exist, but they are strain-specific. Previous outbreaks have largely involved the Zaire strain, for which approved vaccines such as Ervebo are available.
The Bundibugyo virus, however, has only caused two previously recorded outbreaks in Uganda and DRC.
“In the absence of a specific treatment, care relies primarily on symptom management and intensive supportive therapy aimed at improving patients’ chance of survival,” wrote John Johnson, Vaccination and Epidemic Response Advisor at Medecins Sans Frontieres (MSF).
This includes oxygen therapy, fluid replacement, infection prevention measures and supportive critical care, particularly in remote healthcare settings where medical infrastructure can be limited.
A programme manager for MSF told BBC News that she is extremely concerned about the inability to get resources to the country.
Director-General for WHO Tedros Adhanom Ghebreyesus said WHO is supporting national authorities across multiple areas of the response, including development of a clinical trial alongside Africa CDC and the Collaborative Open Research Consortium on filoviruses.
“We have also released $3.9m from the WHO Contingency Fund for Emergencies,” he said during a briefing for Africa CDC.
Philanthropic organisation the Gates Foundation has also pledged $15m to support the emergency response to Ebola.
The United Nations Environment Programme previously warned that, at the scale of Covid-19 vaccine distribution, cold-chain failures could result in the loss of up to one billion doses globally.
The organisation supported the Africa Centres of Excellence for Sustainable Cooling and Cold Chain (ACES), an initiative aimed at improving vaccine and food distribution infrastructure across the continent.
Earlier this year, ACES convened at the UK-Rwanda Climate Partnership Conference attended by Rwanda’s Minister of Environment Bernadette Arakwiye, who described cooling infrastructure as an invisible but fundamental part of healthcare resilience.
Arakwiye said scaling cold-chain infrastructure, including packhouses, cold rooms and refrigerated logistics, should remain a priority.
