By: Christopher Sirota, CPCU
NPR's Planet Money takes a closer look at the global supply chain for vaccines in their December 2020 podcast (includes transcript).
How many vaccines will the world need?
Firstly, for an order of magnitude, the podcast highlights that, excluding the seasonal flu vaccine, the pre-pandemic global production of vaccines is estimated at three to five billion doses; since the current COVID-19 vaccines likely will require two doses, the estimated number of doses needed for the world is about three times the normal output, or 12 billion doses.
How on this world will those doses be distributed?
Apparently, discovering and successfully trialing effective COVID-19 vaccines in a relatively short time may be as complicated as what comes next: packaging and distributing them.
Making the glass vaccine vials
Per the podcast, special shock-resistant medical-grade, low-temperature resilient glass vials are required; the glass is called borosilicate glass. To manufacture such glass several ingredients (silicon, and various minerals) are sourced from many regions including Africa, Australia, Brazil, China, Europe, India, and South America. As the name implies, boron is likely a critical ingredient, and it is reportedly sourced mostly from a single country: Turkey.
The podcast explains further that after the borosilicate glass tubes are made from the molten glass in 5 different melting plants, they are shipped "to one of 16 cutting plants in places like Argentina, Mexico, the U.S., Switzerland, Germany, Indonesia, China [where] the glass tubes get cut into vials, syringes and cartridges."
No vial shortage forecast
According to one vial manufacturer interviewed for the podcast, COVID-19 vaccine makers have ordered vials in advance, and steps are being taken to avoid bottlenecks in supplying vials for the vaccines, despite vial manufacturers also continuing to maintain a supply for other drugs such as for cancer treatments.
The next stop for the vials would, as explained in the podcast, be the pharmaceutical companies where they are cleaned, sterilized and filled with, likely, more than one dose each of a vaccine to reduce the number of vials needed.
Keeping the vaccines cold…really cold
Since the current COVID-19 vaccines require either low or ultra-low temperatures for storage, various means have been reportedly planned to do so: one company has designed "their own boxes with thermal sensors and GPS trackers for their frozen vaccines to travel in."
The podcast explains that there likely are not enough freezers available at all the points along the vaccine supply chain so some airlines and hospital systems are planning to use dry ice; dry ice also has reportedly some transportation issues to consider; for example, if a cooler is not airtight, the ice can sublimate and disappear in about an hour.
Can air cargo networks alone connect the world to the vaccine?
The podcast concludes with a description of the order of magnitude of the air travel needed to support the vaccine distribution around the world. Firstly, it is estimated that the distribution would need the equivalent of 8,000 cargo planes filled with 100 tons of vaccine each to complete the enormous task.
Quick reality check: per the podcast, there are only about 2,000 cargo jets available globally, and 27,000 passenger jets. Therefore, the podcast explains, global distribution will rely on passenger jets as well, some with their seats intact, some with seats removed. Notably, since passenger flights have reportedly decreased by about 40%, this may limit the air transport network's ability to reach more secluded regions.
Also, of note, many regions will not reportedly be able to handle a large amount of vaccine due to limitations on the ground, such as lack of cold storage space, so some flights will be limited in how much can be delivered each trip.
Once on the ground, vaccines face more challenges
Lastly, the podcast speculates that to increase efficiency, regional hubs will be created so that trucks will deliver to fewer locations that are better equipped to handle the vaccine storage.
Of further interest, the Wall Street Journal notes a difference between windows of time allowed for different vaccines after they are thawed: one type can be refrigerated for up to 30 days while another only for five.