[Rondec]

Yeah but the AZ vaccine is far cheaper at about 2.38 per dose as opposed to over 20 for the mRNA ones. The AZ/J&J ones are also far easier to produce and will be produced in the billions by countries all over the world.

Plus, they're far easier to store since they can be stable at regular freezer temperatures rather than the deep freeze temps of the mRNA vaccines which makes deploying it much easier.

I think if it turns out we need to be revaccinated every 6 months it won't be the biggest deal.

I don't think anyone thinks you will need to be vaccinated every six months -- at least with the mRNA vaccines. Indications are that antibodies tend to last at least a year, maybe longer. Moderna COVID vaccine may offer two years of protection: CEO

To me, the big question, as I mentioned is mutation, not loss of antibodies. So, if COVID mutates the spike protein, then you would need revaccination. But it would be a different vaccine, not a booster of the one you had already gotten.

[slartibartfast01]

I do wonder how they do it. Can you get him to explain how they manage to cool that low?

I got the impression they used liquid nitrogen but that may just be for transportation.

[dstar]

TREATMENTS
Why Does Pfizer's COVID-19 Vaccine Need To Be Kept Colder Than Antarctica? Look this publication on NPR 11/17/20 full explanation done
I can’t copy it’s to big publication

[Serkevan]

I do wonder how they do it. Can you get him to explain how they manage to cool that low?

Conceptually, it's not too different from a refrigerator, just has extra steps. They use a propane/CO2* cascade with multi-stage compression** - it is, IIRC, quite similar to cascades used for LNG (but of course at a smaller scale, and needing -80ºC instead of -160ºC helps a lot - with LNG you are banking hard on the evaporation of LNG to keep the fluid cold enough). I found it interesting that the compressors they use are just some kW and don't have to run at full load once the temperature is down. The key point here is that the useful volume is fairly small and the enclosure is very thickly insulated, so the heat transfer is slow once you get down to the target temperature.

*nowadays the EU regulations for freon fluids are very stringent with regards to greenhouse potential, so hydrocarbons are the best options.

**So instead of having a single compression/evaporation circuit like in a normal fridge, you chain together different gasses at different pressures to get to progressively colder temperatures - the coldest gas is the one in contact with the enclosure.

[gaweidert]

TREATMENTS
Why Does Pfizer's COVID-19 Vaccine Need To Be Kept Colder Than Antarctica? Look this publication on NPR 11/17/20 full explanation done
I can’t copy it’s to big publication

Two companies in the US are working on more conventional vaccines and they are a one shot only deal. Stores well at normal refrigerator temperatures too. However the CDC in the US is keeping them on a slow track. Initial trials in the UK have gone well. This would be my preferred vaccine.

[MarkJerling]

Conceptually, it's not too different from a refrigerator, just has extra steps. They use a propane/CO2* cascade with multi-stage compression** - it is, IIRC, quite similar to cascades used for LNG (but of course at a smaller scale, and needing -80ºC instead of -160ºC helps a lot - with LNG you are banking hard on the evaporation of LNG to keep the fluid cold enough). I found it interesting that the compressors they use are just some kW and don't have to run at full load once the temperature is down. The key point here is that the useful volume is fairly small and the enclosure is very thickly insulated, so the heat transfer is slow once you get down to the target temperature.

*nowadays the EU regulations for freon fluids are very stringent with regards to greenhouse potential, so hydrocarbons are the best options.

**So instead of having a single compression/evaporation circuit like in a normal fridge, you chain together different gasses at different pressures to get to progressively colder temperatures - the coldest gas is the one in contact with the enclosure.

Aha. Thank you. Very interesting.

[ZombieArmy]

I don't think anyone thinks you will need to be vaccinated every six months -- at least with the mRNA vaccines. Indications are that antibodies tend to last at least a year, maybe longer. Moderna COVID vaccine may offer two years of protection: CEO

To me, the big question, as I mentioned is mutation, not loss of antibodies. So, if COVID mutates the spike protein, then you would need revaccination. But it would be a different vaccine, not a booster of the one you had already gotten.

I think most people will not be getting the mRNA version of the vaccine for logistical reasons. Even if temps aren't a problem the extreme expense of them really puts a damper on things. The DNA versions of the vaccines will be produced by many different companies en masse across the world.

[dstar]

Two companies in the US are working on more conventional vaccines and they are a one shot only deal. Stores well at normal refrigerator temperatures too. However the CDC in the US is keeping them on a slow track. Initial trials in the UK have gone well. This would be my preferred vaccine.

You correct Novavax and Novavax dual/covid-flue
Very good trail data probably will be next months or so ready

[Rondec]

You correct Novavax and Novavax dual/covid-flue
Very good trail data probably will be next months or so ready

I guess we'll see. Novavax just started recruiting 30,000 volunteers for their trial at the tail end of December. I would be surprised if it is late spring before they get that number recruited and hit their data marks -- 170 infections or whatever they are shooting for.

I'm not sure why AZ's vaccine isn't approved in this country, but apparently the FDA has asked them to test the half dose/whole dose regimen and they are recruiting for that right now. Certainly that vaccine is being used in the UK and Pakistan already. We know it works -- maybe not as well as the mRNA vaccines, but not sure why they wouldn't give it emergency approval.

Janssen is actually closer to finishing Phase III trials than the AZ or Novavax. They had already recruited 45,000 people for their trial in the middle of December.

[MarkJerling]

A bit of a grim milestone this week: 400,000 deaths in the USA, over 2 million worldwide and almost a 100 million cases worldwide. Lets hope the vaccine rolls out quickly and effectively.

[ChrisPlatt]

On The World radio program yesterday I heard a report that in Indonesia and some other predominantly Muslim countries
there is resistance to Sinovac due to the mistaken notion that it contains pork ingredients and is therefore haram (forbidden).

Chris

[timb64]

On The World radio program yesterday I heard a report that in Indonesia and some other predominantly Muslim countries
there is resistance to Sinovac due to the mistaken notion that it contains pork ingredients and is therefore haram (forbidden).

Chris

We are not doomed.....

The top Muslim body in Indonesia have declared it halal (permissable) pending a final decision from its Food and Drug Supervisory Agency on its safety quality and efficacy.

Indonesia: Muslim body declares Chinese vaccine halal

Indonesia is also undertaking one of the biggest vaccination rollouts in the world and prioritising those of working age.

https://news.sky.com/story/covid-19-indonesia-vaccine-rollout-bucks-trend-by...tions-12188490

[35mmfilmfan]

A bit of a grim milestone this week: 400,000 deaths in the USA, over 2 million worldwide and almost a 100 million cases worldwide. Lets hope the vaccine rolls out quickly and effectively.

To add some historical data to this - the flu epidemic of 1918 is known to have killed at least 50,000,000 people. I was going to add something about floods and plagues, but was concerned that might violate the edict concerning religious comments.

[Rondec]

To add some historical data to this - the flu epidemic of 1918 is known to have killed at least 50,000,000 people. I was going to add something about floods and plagues, but was concerned that might violate the edict concerning religious comments.

I really believe that without modern medicine, the death toll from COVID would be in the millions in Europe and North America -- basically anywhere with older populations and a lot of congregating indoors with heated/cooled rooms. The United States has averaged over 100,000 people in the hospital each day for the last month and a half. I really do think that the majority of those would have died before the mid twentieth century.

I think it likely that there will be 500,000 dead in the US before things calm down, but it would have been four or five times that without an early roll out of a vaccine, high flow oxygen, ECMO, and dexamethasone.

[Serkevan]

The flu pandemic of 1918 (really any pandemic before the 1950s) is not comparable to today, for a single word: antibiotics. The vast majority of H1N1 flu deaths had bacterial presence in the lungs, which means opportunistic bacterial pneumonia. Without treatment that's pretty much a death sentence, no matter how healthy you are.

I mean, it's also not comparable because malnutrition was rampant in ye olden times and that's a huge issue for immunity, plus hygiene standards, plus... you get the point. Contrast and compare the H1N1 pandemic of 2009, which was problematic but managed fairly easily.