OT: Pfizer vaccine and cold storage

[Chris Hogg]

I don't understand why there's all this fuss about the difficulties in handling this vaccine due to having to store it at -70 to -80C, i.e. packed in dry ice (solid CO2). Decades ago all the little ice cream vans that did the rounds of housing estates or were parked on sea fronts used dry ice to keep the ice cream cold, before they had built-in refrigerators. It was commonplace. So why all the fuss about storing the vaccine? Just line a big box with a thick layer of expanded polystyrene, part fill it with dry ice, store in a well-ventilated room - problem solved. Much ado about nothing, it seems to me!

[Brian Gaff (Sofa]

It is not a problem here in the UK but it is in countries where the places where the people are are remote and require a long overland journey to get there, then protracted storage while people actually come in from the surrounding land. Brian

[Jeff Layman]

It's more to do with the availability of dry ice, I think. This is a US article, but it probably applies to Europe:

If the manufacturing plants have been partially shut down due to Covid, that adds another dimension in getting them running again.

I haven't seen it mentioned, but I wonder too if there are sufficient supplies of temperature monitors to place in the boxes.

[David]

I don't understand why there's all this fuss about the difficulties in handling this vaccine .........

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The media trying to create a mountain out of a molehill!

As you say, storing and transporting something at -70C isn't a problem in most countries.

Remember most journalists aren't technically minded and the limit of their thinking when it comes to cold temperatures is their domestic freezer and most importantly, if it can make ice for their drinks!

David

[Bob Eager]

Which may be the case here. 'long' in time.

[Chris Hogg]

That I can understand, but here in the UK? The media and indeed the doctors and other health professionals being interviewed on TV here seem to think it's a big issue for us.

[Andy Burns]

From footage on the news yesterday, that's what they're doing, no doubt it's a bit different and therefore "newsworthy" ...

[Martin Brown]

But they were only holding the ice cream at about -20C as a result. This vaccine would be rendered useless if it ever got that warm in transit.

One of the problems is that with the breweries shut down there is a shortage of pure CO2 for making the dry ice (and fizzy soft drinks).

You do also need to have the sort of industrial fridges that can hold the vaccine at that temperature until it is needed. Freezers that will do -20C are two a penny only quite specialist kit does -80C.

Hospitals have them but GP practices generally do not.

The vaccine has a very short life span once it is thawed ready for use.

[Andy Burns]

I heard that once it arrived, they thawed it down to convenmtiomnal fridge temperature and it was OK for a week like that, I imagine it's going to be used about as fast as it arrives, provided they can get people in through the doors?

[nightjar]

AIUI, the problem is the terms of the approval. At present, only bulk supplies are approved and they only have a shelf life of 10 days when kept as shipped. The MRHA is working on extending the approval, but that takes time.

[Andy McKenzie]

Yes - it does seem all a bit overblown. Put your vaccine in a special fridge at the hospital, take out the stuff you plan to use that day. Drive to where you want to use it - care home, GP surgery etc. Use it. Job done. Or are there many locations in the UK that are more than 5 days travel from a hospital?

[Chris Green]

Surely there are vehicles with refrigerators that can keep the vaccine at -70C, no need for any dry ice. They certainly said on TV recently that NHS hospitals *already* have refrigerators capable of storing the vaccine - that was given as an advantage over another that required lower (and not widely available) temperatures.

[Scott]

This seemed to be exactly the approach at Antwerp airport, shown on News at Ten last night.

[Scott]

I think that is for the first stage of distribution. Once they are taken out to individual care homes and GP surgeries, I cannot image such specialised vehicles will be available or used.

[newshound]

Not sure how much dry ice production there is in the UK now (probably more LN given the number of SEMs around). We sometimes get frozen dog food that comes, supposedly, with dry ice but all we ever find in the boxes are some empty, damp, perforated plastic bags.

[Andy Burns]

Doesn't it matter more how much production there is in Belgium?

[Tim Streater]

My question is more along the lines of why does it have to be kept so cold?

[The Natural Philosopher]

I suspect cos its partly alive, and needs 'suspended animation'.

[Tim Streater]

Less so than a virus, I would have said. The RNA fragment is supposedly inside a lipid shell, which also supposedly allows it to penetrate a cell so that the RNA can start to be used to replicate Covid's spike proteins. But if this is the case, why do viruses need a mechanism such as the spike proteins to effect cell entry?

[nightjar]

Because, at present, they only have data on its shelf life at those temperatures and the approval is based on that data. It is thought they are testing samples to see whether they stay stable at higher temperatures, but that is very much a project for the future.