Cold chain infrastructure hangs over bird flu vaccine prepCold chain infrastructure hangs over bird flu vaccine prep

Epidemiologists, physicians, and other experts are expressing their concerns about the potential for an avian flu epidemic. They argue that we may be just one unlucky reassortment event away from the flu becoming transmissible from human to human. In the face of this, researchers are investigating novel mRNA vaccines for their quick development and adaptability to an emerging viral threat. 

Unfortunately, mRNA vaccines require significant cold chain infrastructure to remain usable – a restriction that can make delivering them in lower- and middle-income countries (LMICs) a challenge. 

David Hamer, professor at Boston University, has spent his life studying infectious disease with a focus on tropical climates. He has seen firsthand how cold chain infrastructure can be a barrier to delivering therapeutics in hotter climates. He spoke with our sister site, Tides Global, about how climate change and logistical factors directly impact patient access to lifesaving biologics. 

Quotes have been lightly edited for clarity.

Cold chain logistics and tech transfer/IP held up vaccine access in LMICs during the COVID pandemic. In the event of an avian flu outbreak, are LMICs in a better position, or are we at risk of repeating past mistakes? 

I don't think we've resolved a lot of the problems. It's going to be the Coalition for Epidemic Preparedness Innovations (CEPI)  and Gavi and other organizations that are going to have to step up and get funding from different parties to help coordinate this.  

The cold chain is still a problem, especially for mRNA vaccines. It's a little stronger in some places, but it's still not great. Heat-stable vaccines or vaccines that only require refrigeration rather than freezing are going to be a lot easier to distribute and maintain a degree of quality. 

I've done a lot of work in Sub-Saharan Africa over the years, and it's really a problem. I've worked in Zambia for 20 years, and Zambia is almost completely dependent on hydroelectric power. They had so little rainfall this year. This is a climate change effect. They basically had to do 21 hours a day of load shedding, so people only had electricity for three hours a day across the country for a couple months.  

That means if you want to plug in your phone, you've got to leave it plugged in and hope your electricity comes on between two and five in the morning. Then you charge your devices for the day, and you have to be careful – maybe you charge a backup, or you put in solar panels or whatever.  

But that makes it really hard to maintain a cold chain, because you're going to have to pay for diesel fuel to run generators or put in solar panels and other things that are little bit out of reach still in many low-income countries. I fear that some parts of the world are just not ready for it, and that that depending on their power sources, they may be greatly affected by climate change, and that may make it harder for vaccine storage and distribution. We have to be ready to help them.  

But we don't work with the WHO anymore, so we can't do that... 

Read more of our in-depth interview with Hamer about vaccines and pandemic preparedness at Tides Global. 

Søren Hough is the editor of Tides Global, which covers emerging peptide, mRNA, oligo, and genome editing therapeutics.