Coronavirus Sars-CoV-2/Covid-19 Megathread

[Valmy]

Fauci believes, in America at least, distribution could begin by end of year.

To think, Trump would have loved this news last Monday.

Man this is exciting. I might get what I really want for Christmas after all.

[Valmy]

So this is the hopeful period before we all realize the vaccine turns people into mindless zombies, right? 

No that is the vaccine that cures cancer that is going to do that.

[viper37]

A few weeks back I saw the head of the pharmacy industry trade body say there are significant manufacturing and logistical challenges faced by coronavirus vaccines, he estimated 12-17 billion doses would be required, whereas the largest annual production so far is the polio vaccine, at just 450 million doses a year. 
 

Why would we need double the world population in doses?

because we may need more than one shot.  We do not know yet if it will require a recall.

[Sheilbh]

I've heard talk on NPR about multiple rounds of shots.

Yep - 2 shots and probably multiple vaccines. It's very unlikely that one vaccine will be a silver bullet.

[Malthus]

Fauci believes, in America at least, distribution could begin by end of year.

To think, Trump would have loved this news last Monday.

Trump of course is now saying the FDA and Pfizer deliberately held back the news until after the election

Heh it is looking like the vaccine may be ready just as soon as Trump is dragged out of the White House ... you can see why, in the fact-free, paranoid mental world Trumpites live in where everything revolves around Trump, this can be seen as screwing him. 😄 Assuming the vaccine works and is available on that date, it will literally appear that the pandemic is a "Trump" pandemic. Fitting in that he made it worse, but the timing of its end is purely fortuitous.

[Sheilbh]

I don't think it's crazy that Pfizer would hold back an announcement like this until people have voted. It's huge news that is causing real optimism in all the right places and I think you would want to make sure as much as possible that wasn't perceived/tarnished politically. The safest way to do that is to hold over the announcement until people are no longer casting their votes.

[Gups]

I don't think it's crazy that Pfizer would hold back an announcement like this until people have voted. It's huge news that is causing real optimism in all the right places and I think you would want to make sure as much as possible that wasn't perceived/tarnished politically. The safest way to do that is to hold over the announcement until people are no longer casting their votes.

If so, maybe they could give the UK Govt lessons on how to prevent leaks.

[The Minsky Moment]

I don't think it's crazy that Pfizer would hold back an announcement like this until people have voted..

OK but is there any basis to think they did that?  I haven't seen it.

[The Minsky Moment]

There isn't much information I've seen about the Pfizer study other than the total size of COVID positives (94) across the test and control groups and the finding that rates of symptomatic infection are 90% lower in the test group.  That is a very nice result but standing alone it's not clear how effective it really is.

[Valmy]

I don't really understand what exactly this announcement means. Is this thing proven to be effective and we are all ready for production or is this just one good result out of many that are required?

[Sheilbh]

I don't really understand what exactly this announcement means. Is this thing proven to be effective and we are all ready for production or is this just one good result out of many that are required?

From the BBC:

Covid vaccine: First 'milestone' vaccine offers 90% protection
By James Gallagher
Health and science correspondent

The first effective coronavirus vaccine can prevent more than 90% of people from getting Covid-19, a preliminary analysis shows.

The developers - Pfizer and BioNTech - described it as a "great day for science and humanity".

Their vaccine has been tested on 43,500 people in six countries and no safety concerns have been raised.

The companies plan to apply for emergency approval to use the vaccine by the end of the month.

No vaccine has gone from the drawing board to being proven highly effective in such a short period of time.

There are still huge challenges ahead, but the announcement has been warmly welcomed with scientists describing themselves smiling "ear to ear" and some suggesting life could be back to normal by spring.

"I am probably the first guy to say that, but I will say that with some confidence," said Sir John Bell, regius professor of medicine at Oxford University.

How effective could it be?

A vaccine - alongside better treatments - is seen as the best way of getting out of the restrictions that have been imposed on all our lives.

The data shows that two doses, three weeks apart, are needed. The trials - in US, Germany, Brazil, Argentina, South Africa and Turkey - show 90% protection is achieved seven days after the second dose.

However, the data presented is not the final analysis as it is based on only the first 94 volunteers to develop Covid so the precise effectiveness of the vaccine may change when the full results are analysed.

Dr Albert Bourla, the chairman of Pfizer, said: "We are a significant step closer to providing people around the world with a much-needed breakthrough to help bring an end to this global health crisis."

Prof Ugur Sahin, one of the founders of BioNTech, described the results as a "milestone".

When will the vaccine be available?

A limited number of people may get the vaccine this year.

Pfizer and BioNTech say they will have enough safety data by the third week of November to take their vaccine to regulators.

Until it has been approved it will not be possible for countries to begin their vaccination campaigns.

The two companies say they will be able to supply 50 million doses by the end of this year and around 1.3 billion by the end of 2021. Each person needs two doses.

The UK should get 10 million doses by the end of the year, with a further 30 million doses already ordered.

Who would get it?

Not everyone will get the vaccine straight away and countries are each deciding who should be prioritised.

Hospital staff and care home workers will be near the top of every list because of the vulnerable people they work with, as will the elderly who are most at risk of severe disease.

The UK is likely to prioritise older resident in care homes and the people that work there.

But it says a final decision has not been made, saying it will depend on how well the vaccine works in different age-groups and how the virus is spreading.

People under 50 and with no medical problems are likely to be last in the queue.

Are there any potential problems?

There are still many unanswered questions as this is only interim data.

We do not know if the vaccine stops you spreading the virus or just from developing symptoms. Or if it works equally well in high-risk elderly people.

The biggest question - how long does immunity last - will take months or potentially years to answer.

There are also massive manufacturing and logistical challenges in immunising huge numbers of people, as the vaccine has to be kept in ultra-cold storage at below minus 80C.

The vaccine appears safe from the large trials so far but nothing, including paracetamol, is 100% safe.

How does it work?

There are around a dozen vaccines in the final stages of testing - known as a phase 3 trial - but this is the first to show any results.

It uses a completely experimental approach - that involves injecting part of the virus's genetic code - in order to train the immune system.

Previous trials have shown the vaccine trains the body to make both antibodies - and another part of the immune system called T-cells to fight the coronavirus.

What has the reaction been?

The UK's chief medical advisor Prof Chris Whitty said the results showed the "power of science" and was a "reason for optimism" for 2021.

The US president-elect Joe Biden said it was "excellent news".

"It is also important to understand that the end of the battle against Covid-19 is still months away," he added.

The UK Prime Minister's official spokesman said the results were "promising" and that "the NHS stands ready to begin a vaccination programme for those most at risk once a Covid-19 vaccine is available".

Prof Peter Horby, from the University of Oxford, said: "This news made me smile from ear to ear.

"It is a relief... there is a long long way to go before vaccines will start to make a real difference, but this feels to me like a watershed moment."

Sir John Bell's comment was that it rolls the pitch for other vaccines. So there's been indications all through this that vaccines will work. This just increases the likelihood that some or all of the other vaccines under development may work. That's key because we're not going to have a perfect vaccine within a year of a new virus so we'll probably all end up on one or other of these or maybe a combination.

Edit: I actually feel like the key bit is that they've got enough safety data to go for approval which might mean going to manufacture this year. (Total aside - but imagine how we'd all have felt in the first week of April if we were told we might get back to normal in spring 2021 )

OK but is there any basis to think they did that?  I haven't seen it.

No - it just doesn't strike me as crazy.

[Syt]

"Only" 6100 cases today, but 23% positive test rate and contact tracing is not able to keep up, so the unseen numbers are likely a lot higher at the moment. Currently ca. 40 deaths per day.

[The Minsky Moment]

The problem with doing vaccine tests is you can't measure directly what you want to measure: namely, infection rates of people exposed the virus.   Pfizer had tens of thousands of people in their study but the vast majority presumably had no exposure and thus are irrelevant to the study.  There is no way to track or figure out how many were exposed.  Pfizer can only draw inferences based on the proportions of identified cases in their test vs control group.  So strictly speaking it is not accurate to say their study showed 90% efficacy in the group - it would more accurate to say that the results are consistent with a 90% effective vaccine.  They are also consistent with a 95% effective vaccine or a 90% vaccine or possibly even an 80% effective vaccine.  It is a probability distribution not a single fixed number.  The difference between 80% effective and 90% effective may not seem that big, but it is significant - the former means twice as many expected failures as the latter. One also has to account for the reality that many people will refuse the vaccine or fail to complete the full course properly.

An even bigger potential problem is that Pfizer hasn't revealed the composition of the infected sample and that even Pfizer doesn't know for sure the composition of those exposed.  If that population differs materially from the overall population then the results must carry an asterisk.  I.e. a vaccine that is 100% effective when administered to young healthy people but not very effective for elderly high risk has issues, particularly if the vaccine does not prevent transmission . . .

[alfred russel]

Minsky, while all that stuff is relevant, I think you are wrong.

It is estimated you only need something like 60% coverage to get to herd immunity. Possibly even less. 80% effectiveness is plenty if you can get this effectively rolled out.

[Sheilbh]

Incidentally some useful information on how vaccine trials work here:
https://twitter.com/nataliexdean/status/1310613702476017666

And on this one in particular here:
https://twitter.com/nataliexdean/status/1325820512946302977

By an academic specialising in vaccine study design.