Corona Daily 318: Place Euphoria in Frozen Storage

I meet lots of people who are euphoric about Covid-19 vaccines. With the amount of investment and dozens of candidates running trials, the world will get a vaccine anytime soon, signalling curtains on the pandemic. Pfizer has one of the three vaccines that have advanced to phase 3 trials. God forbid Pfizer wins the race by getting approval for its vaccine. Why so?

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Vaccines travel a long way from the factory to the injectible arm – often across continents. Most standard proven vaccines need to be maintained at temperatures between 2C (36F) and 8C (46F) throughout the cold chain. If the vaccine becomes too warm for too long, it can become ineffective. (These two documents state in lovely details: all that you ever or never wanted to know about cold chains.)

Now along comes Pfizer and develops a Covid-19 vaccine that must be maintained at -80 C (-112 F) throughout the cold chain. Great if all of us were living on the South Pole. Fedex had invested in freezers for the 2009 H1N1 epidemic, they have doubled their capacity. UPS is building a freezer farm with ultra-cold freezers to store millions of doses.

Additionally, staff has to be trained and equipped. You can’t operate the freezer unless you are wearing personal protective equipment (not to be confused with the Covid PPE), specific gloves and special goggles. Of course, you can’t invite the whole world to a farm in Louisville to get vaccinated. The special operators must take the vaccines out to the trucks.

That has to be done with dry ice. But dry ice on flights needs special approvals. Because when it melts, it emits carbon dioxide, potentially making the plane unsafe for pilots and crew.

The trucks, planes, warehouses, clinics, chemists will require dry ice. Dry ice is made of CO2, which is a byproduct while producing ethanol. The demand for ethanol moves in line with gasoline. But people are driving less, so the ethanol production has slumped. As a result, dry ice is in huge shortage.

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Meanwhile, the American glass company Corning has warned that glass cracks in such extreme cold. Meaning the glass vials will be defunct. Corning is now developing a new type of glass that can withstand these temperatures.

In theory, the Pfizer vaccine can be shipped in “dry ice pack” boxes. But that dry ice will need to be replenished within 24 hours of receipt. The shipping carton must be closed within one minute of opening, and should not be opened more than twice a day. Again, dry ice handlers need to be trained at all stages, because of the risk of asphyxiation.

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Your chemist or GP is unlikely to invest in the necessary equipment. Even in developed countries, the probable scenario is people going to a centralized location, such as a hospital with great super freezers, and queuing up for a vaccine. With such stringent cold chain conditions, only 2.5 billion people in 25 countries would be able to access the vaccine. About 5.5 billion people in 180 countries in Asia and Africa will be deprived for lack of infrastructure.

Globally, half of the vaccines are wasted because of the supply chain logistics. India, a developed vaccine country, wastes 25% as a minimum, and up to 50% of BCG vaccines. Reliable electricity supply is key. In Uganda, 70% of the health care facilities have electricity going off for a few hours every day.

Moderna vaccine is slightly warmer, requires -20 C (-4 F). Oxford and Johnson and Johnson vaccines expect normal 2C-8C conditions.

People living in areas with unreliable power supply should not be euphoric about the potential vaccine.

Ravi