Coronavirus Sars-CoV-2/Covid-19 Megathread

[Sheilbh]

Also not helpful, I don't think, to have every news org putting out headline that you need to have that gap...beyond say supporting JCVI guidance. I've already seen people saying though that Fauci and others need to apologise to the UK / people fretting they got their 2nd dose too soon.  News orgs seem to be doing nothing to contextualize the results of this small study.

Agreed. I think generally the JCVI have done a very good job of explaining their reasoning - so I don't know on vaccinating children but I look at that link I posted earlier and I can see the issues they've considered and how they get to their conclusion. Similarly Dr Wei Shen was excellent on explaining the rationale for their shift on AZ for younger people both explaining the decision but also, as you say, they were quite good at not creating a gap where lots of people could speculate (which I think was a mistake made by the EMA and FDA - on J&J) and the press just report "VACCINE HALTED". Similarly I don't think taking a really strict line without providing an explanation works - even if the later work does help explain it.

I think it's tough for regulators because the public not just medical/pharma community are watching. But I don't think it helps to issue a position without immediately being able to provide an explanation for your decision - even if it is a holding pattern. I think that's one of those BAU things that are fine in the industry for normal processes but harm trust or raise doubts in this context that don't realy need to exist.

[Tamas]

The study was done quite a while after the decision was made to use a 12 weeks gap I assume? That makes me skeptical about the whole "English study shows England was perfectly right to diverge from what the rest of the world has been doing" thing.

[Grey Fox]

The study was done quite a while after the decision was made to use a 12 weeks gap I assume? That makes me skeptical about the whole "English study shows England was perfectly right to diverge from what the rest of the world has been doing" thing.

We did it too.

[garbon]

The study was done quite a while after the decision was made to use a 12 weeks gap I assume? That makes me skeptical about the whole "English study shows England was perfectly right to diverge from what the rest of the world has been doing" thing.

Yes it looks like first worker in trial was given vaccine after JCVI guidance that ideal period was 8-12 weeks.

[garbon]

Study had a rather unbalanced sample with regards to short vs long interval. I wonder if there were circumstances that drove which interval they were given dose on.

[Sheilbh]

The study was done quite a while after the decision was made to use a 12 weeks gap I assume? That makes me skeptical about the whole "English study shows England was perfectly right to diverge from what the rest of the world has been doing" thing.

Yes it looks like first worker in trial was given vaccine after JCVI guidance that ideal period was 8-12 weeks.

Aren't those two separate things though?

Initially their view was that there were unlikely to be adverse effects from delaying the second dose to 12 weeks and it was better to have more people with the protection of one dose than a smaller number with both doses (0.8*2 is more than 0.95). It was basically about what's the best approach given you have very limited supply. But I think they always said they'd look at the data and adjust if necessary.

This study came after that but seems to be saying something different - that they think there are clinical benefits to an 8-10 week schedule which is why the NHS shouldn't be letting people get their second dose after 4-5 weeks (at which point, clearly, supply isn't the issue).

"English study shows England was perfectly right to diverge from what the rest of the world has been doing" thing.

The WHO and EMA are both also fine six week delays (which is less than the UK but double what was trialed), and as GF mentioned Canada also took this approach. I don't think the UK approach was that divergent it was just early so controversial.

[garbon]

Aren't those two separate things though?

Initially their view was that there were unlikely to be adverse effects from delaying the second dose to 12 weeks and it was better to have more people with the protection of one dose than a smaller number with both doses (0.8*2 is more than 0.95). It was basically about what's the best approach given you have very limited supply. But I think they always said they'd look at the data and adjust if necessary.

This study came after that but seems to be saying something different - that they think there are clinical benefits to an 8-10 week schedule which is why the NHS shouldn't be letting people get their second dose after 4-5 weeks (at which point, clearly, supply isn't the issue).

Yes, original stance was that okay to push so they could maximise use of supply. Now though they have a study that justifies there was no harm done and in fact what they did was even better than what other countries had done. That's the oh so convenient factor.

Note, I was briefly confused by your post as 'adverse effects' for pharma generally means side effects from the drug.

[Sheilbh]

Sorry - yeah I actually thought of that and should have been clearer. I meant they didn't think it would significantly weaken the protection from the vaccine.

I get the oh so convenient point - but I I've not seen anything else from JCVI that would suggest they wouldn't change policy if it showed that actually 3 weeks in is the optimum time. I wonder if they might have needed a little more evidence than this to shift to that position though - I'm assuming this is why they moved from 12 weeks to 8.

But I suppose the only options take a risk and be prepared to adjust or delay the vaccine roll-out to do studies which just isn't a plausible (or ethical)

[Tamas]

Study had a rather unbalanced sample with regards to short vs long interval. I wonder if there were circumstances that drove which interval they were given dose on.

It's not exactly rare that scientists arrive to a conclusion then formulate a test to prove it.

[garbon]

Study had a rather unbalanced sample with regards to short vs long interval. I wonder if there were circumstances that drove which interval they were given dose on.

It's not exactly rare that scientists arrive to a conclusion then formulate a test to prove it.

Are you describing a hypothesis?

[Sheilbh]

On covid studies - this one strikes me as important:
https://www.bbc.co.uk/news/health-57930214

It's still a pre-print but basically the got bunch of schools together. Half were required to quarantine/self-isolate if there were cases (this is the norm) and the other did daily rapid lateral flow tests instead. There was no difference in viral spread or transmission but the rapid lateral flow test significantly decreases the amount of time kids have to spend quarantining at home and increases the amount of time they can spend in school:

The University of Oxford study asked half of the schools to continue with the current policy while the other half invited close contacts of positive cases to take lateral flow tests every day at school. If they tested negative, they were allowed to attend school as normal.

Involving more than 200,000 students and 20,000 staff, the study found no evidence that the rate of students and staff developing Covid symptoms was different in the group doing daily testing compared with the group of close contacts isolating at home.

The study could not prove that the policy cut school absences, but the researchers claim that daily contact testing could reduce absences by up to 39%.

Overall, the study found:
    daily testing of students and staff who were exposed to Covid was as effective as isolation at controlling spread
    around 98% of contacts in the trial did not develop Covid during the isolation period
    rates of Covid in school staff were lower than in students and mirrored community levels

The researchers said pupils and staff were more likely to take daily tests because there was no social penalty to doing them, as there was with isolation when friends had to be named as close contacts.

Although they admit lateral flow tests aren't perfect, they say the tests are good at identifying people who are most infectious, who can then be withdrawn from school.

It seems like it's a big enough study to be useful for policy next school year - and hopefully in other countries that are working out what to do with schools. Also it might help reduce the inequality that's been showing up in tests/education around the worlds because if you've got money/are working from home it is more likely that you can help your kid if they're quarantining, or even have tutors while poorer kids have been falling behind (I think there was a big Dutch study on the unequal effects of school closures and quarantines). This might help even the playing field a little bit if schools can stay open.

[Tamas]

Study had a rather unbalanced sample with regards to short vs long interval. I wonder if there were circumstances that drove which interval they were given dose on.

It's not exactly rare that scientists arrive to a conclusion then formulate a test to prove it.

Are you describing a hypothesis?

No. I was trying to be nice saying they adjusted the parameters of the study to ensure the results will be to their liking.

[garbon]

Study had a rather unbalanced sample with regards to short vs long interval. I wonder if there were circumstances that drove which interval they were given dose on.

It's not exactly rare that scientists arrive to a conclusion then formulate a test to prove it.

Are you describing a hypothesis?

No. I was trying to be nice saying they adjusted the parameters of the study to ensure the results will be to their liking.

[Admiral Yi]

Heard on NPR that 40% of delta cases in the US are in three states: Florida, Texas, and Missouri.

[Josquius]

Is daily covid testing healthy?
Shoving a swab where items aren't meant to be shoved doesn't seem great as a daily thing.