The thrill that greeted the information of a vaccine candidate which may be extremely efficient towards COVID-19 was certainly one thing to behold. If the ultimate outcomes present something just like the numbers quoted within the press launch, then the world can certainly be happy and the scientists behind the scenes very happy with themselves.

One complicating issue would be the upkeep of the chilly chain. Vaccines are fragile merchandise: they should be saved at particular temperatures, and a few are delicate to gentle and should be transported in darkish glass vials. These exact situations have to be maintained all through the vaccine journey, proper till the purpose if you’re within the GP surgical procedure along with your sleeve rolled up and the nurse opens the fridge door to extract the required immunisation.

For instance, let’s say you reside in rural Ghana, in West Africa, and the vaccine itself is coming from the UK. The chilly chain must cowl that vaccine leaving the UK manufacturing website, being loaded onto a automobile and pushed to a storage website close to the airport, shifting on the aeroplane to Ghana, storage in or close to Accra (the capital metropolis), transport to a rural district well being centre, after which probably additional transport in a automobile, and even on foot, throughout troublesome terrain to bodily get to a distant inhabitants.

That closing stage is one thing healthcare staff in Ghana and all low and middle-income nations do many instances a 12 months – for instance, with polio vaccination campaigns – and it may be heroic and typically harmful work. Wherever we dwell on the earth, these individuals deserve our thanks.

Healthcare staff in these settings are well-practised at delivering vaccines in every single place, however you possibly can see the variety of separate steps the place the chilly chain must be maintained. Important package might embody a transportable fridge at the back of a 4×4, or a cool bag that’s carried by hand. These cool luggage might comprise “freezer packs” that preserve the merchandise sufficiently cool for at the very least a number of hours in order that the vaccines don’t spoil.

Eighty beneath

The Pfizer/BioNTech vaccine must be saved at -80⁰C, which is hard. This isn’t an insurmountable drawback, but it surely poses additional logistical challenges. It requires specialist gear often known as “extremely low temperature freezers”. These are usually present in specialist analysis amenities or biobanks.

Since most routine vaccinations require refrigeration or freezing at a lot lesser temperatures, a GP follow within the UK is unlikely to have already got that facility, not to mention a well being centre in rural Ghana.

Governments the world over will now be questioning what number of of those freezers they’ll want to purchase. And at a price of some thousand kilos per unit, plus working prices of perhaps £500-£750 per 12 months, the invoice might get giant in a short time. This type of monetary outlay may additionally be past rural Ghana and different resource-poor settings. It’s not simply the price of shopping for the vaccine itself that we want to consider.

Chilly chain being maintained utilizing ice field whereas transporting polio vaccine.

GiveWell/Wikimedia Commons, CC BY

Over the following six to 12 months, we hope that we’ll find yourself with a number of totally different vaccines. They’ll all have barely totally different benefits and drawbacks, together with issues of effectiveness, security, variety of doses, value and storage necessities. It might be that in high-income nations, vaccinating weak populations with a product that requires two doses and -80℃ storage is workable. In sub-Saharan Africa, a extra helpful product might probably be one which wants one dose and has a much less stringent chilly chain, even when general vaccine effectiveness is barely decrease.

The brief and medium-term future for COVID-19 vaccine improvement seems very thrilling. Nevertheless, success in scientific trials continues to be a great distance from the endgame of a extremely efficient immunisation distributed to all corners of the globe. For now, we await additional improvement with hope, however maybe additionally greater than a bit of expectation.

Michael Head has beforehand acquired funding from the Invoice & Melinda Gates Basis, and the UK Division for Worldwide Growth.