Cold Chain mission: Vaccines

With the outbreak of the COVID-19 pandemic, and subsequent the roll out of the vaccination program in 2021, cold chains have become a concept that a lot of people have become familiar with.

 

We already talked about the Cold Chain in a previous post that you can read in the below link:

 

Cold Chain

 

But with this term now becoming a hot topic, a post of itself should be dedicated to vaccines specific cold chain!

 

Let’s start from the beginning; a cold chain is a temperature-controlled Supply Chain. In particular, the term is used to describe the cold temperature conditions in which certain products need to be kept during storage and distribution.

 

The cold chain is used in the supply and storage of many perishable products, including vaccines, however, maintaining a continuous cold chain in resource-limited places where power supply is unreliable, or even non-existent, is a considerable task.

For vaccines, there are different types of requirements.

 

-    There is an ultralow, or deep freeze, cold chain for vaccines that require -70 degrees C (the Ebola vaccine require this level).

 

-     Next the frozen chain requires -20 degrees C (varicella and zoster vaccinations require this level)

 

-     The refrigerated chain, which requires temperatures between two and eight degrees C (most flu vaccinations only require refrigeration).

 

As an anecdote, the Pfizer COVID-19 vaccine also needs ultracold storage and transportation temperatures as cold as −70 °C, requiring what has been referred to as a "colder chain infrastructure” which has created some issues of distribution as it is estimated that only 25 to 30 countries in the world have the infrastructure for the required ultracold cold chain.

 

If you want to see first-hand how critical cold chain is when distributing vaccines, I recommend watching the series Cold Chain missions, with Ewan McGregor. Here is a taste for it:

Cold Chain Mission - The Congo

 

And if you want more information, check the below document from the World Health Organisation on vaccines cold chain.

Cold Chain vaccines WHO