On now:

UK Science, Research and Technology Capability and Influence in Global Disease Outbreaks
Witness: Sir Patrick Vallance, Chief Scientific Adviser @uksciencechief

https://parliamentlive.tv/Event/Index/c4b7d5c2-5227-4679-ae41-dad08753193a

Science and Technology Committee questioning @uksciencechief on role of scientific advice on @GOVUK policy decisions.

Questioning regarding 'slowness' to apply reasonable policy changes, particularly before results of studies are know (where 'common sense' could be used), such as asymptomatic and symptomatic transmission in care homes.

CSA confirms these are policy changes and are up to govt

CSA: care home advice was available to Govt from February. SAGE does not direct policy, they provide advice to Govt to make policy decisions. SAGE also willing to acknowledge uncertainty in evidence and still advice based on the evidence available.

Qs about diverging from WHO guidance, e.g., on social distancing 1 vs 2m.

Advice given by SAGE on face masks in Feb - Vallance: "masks are of marginal positive value when used in enclosed spaces where crowding may occur and you can't keep 2m distance"

Face masks to be mandatory in shops:

Releasing measures means other measures are sensible. E.g., making workplaces COVID secure.

[Note skirts around face masks question, only quoting as above]

Deputy Chief Medical Officer sat down in interview with PM about face masks and said they could be detrimental.

CMA: "I'm not sure the science has changed dramatically actually, it's sort of accumulating evidence, it's still not overwhelming evidence, and there are really 3...

"... lines of evidence on face coverings. One is experimental mechanistic work, (how droplets and aerosol pass through mask), second, clinical trials regarding what happens when people do or don't wear them, and there the evidence is much weaker, in other words you don't get..."

"95% protection as you might do if you tested that mechanistically, you get some protection, and it varies according to settings, and then there's observational studies which we're now seeing which is what was the impact when masks were introduced in country A or country B..."

"... could you see a difference in the rate of infection, they're quite difficult to interpret because usually the intervention isn't a single thing like a mask, all sorts of other things changed at the same time. You put those 3 lines of evidence together and it reaches the..."

"...conclusion that we did, in April, saying on balance masks have a positive effect, in terms of stopping other people catching it from you, not from you catching it from other people... One of the things the deputy CMO may have been worried about was..."

"... if you wear masks for very prolonged periods, people tend to fiddle with them, take them off, move them, then it;s a bit more tricky to see what the benefit is."

Questions now on immunity:

CMA: the vast majority who get COVID get an antibody response, including neutralising antibodies, which would prevent the virus from causing an effect, it also appears that in some cases antibody levels seem to drop after about 3 months

"Antibodies may not be long lasting, that does not mean that some form of immunity is not long lasting, so we've got other parts of the immune system, we may have memory cells on the B cell side of things, we may also have T cell responses, which are important, and we don't know"

There is much we still don't understand about immunity, and we don't know to what extent a positive antibody means that you are protected against the virus or carrying the virus.

Future leaning:

Data flows need improving. SAGE has never been set up to work for 47 meetings, need to think about how to make it work, largely volunteer academics who help out

"science system across govt and agencies needs to be robust, SAGE is *not* the science system..."

"... it is a science advisory body. And so science within @PHE_uk needs to be in the right place, science in Departments needs to be in the right place, there needs to be enough in order to be able to take the science advice to feed in"

Question regarding has science been over-weighted in the way Govt has managed this pandemic? Have we lacked for a business/economic SAGE?

CMA: we thought about how economics should be integrated into SAGE, it was quite a difficult thing to do...

Treasury is another route [for this].

Q about Prof Woolhouse's comments on harms done by lockdown not being considered.

CMA: not the purpose of SAGE to look at that, but @CMO_England was very clear that there were downsides from an economic perspective which would...

... have significant health effects, and he talked about damage... being direct from the virus, indirect from overwhelming of the NHS, and indirect through economic consequences

"We've been worried a lot about the consequences of this and I think those worries were right"

CMA: Economic input and science could have merged in a better way.

Q: has SAGE made an assessment of the impact of lockdown in terms of lives&health?

CMO has been clear, the way this should be looked at is overall excess deaths. Because then you're looking at the integrated effect of the virus with all the other reasons people may have suffered

Q about COVID spread in air:

"We said so in April. Three potential routes, aerosol, droplets, &surface contact. All 3 are things that need to be taken into account. What we don't know (&don't know for flu yet either) is what the relative importance of the 3 different routes are"

CMA: "the one that we don't think is such a big area, and the WHO doesn't either, is very widespread airborne transmission of the type you can get with measles and so on, we think that's less likely to be an important factor"

CMA: Transmission outside is low.

"We also see from demonstrations that have taken place in the last couple of months that so far we haven't seen an uptick in cases as a result of that, so outside, the risk of transmission, with distancing is pretty low"

CMA: [cloth masks] shouldn't be worn all day in indoor environments.

(A win for no masks in offcies and schools? @SelfHarmNotts @simondolan)

Q: is there a placebo effect from wearing a mask?

CMA: "it's a reminder, you can see from wearing a mask, it reminds you there are things you need to do, there are positive benefits to the messaging that might come with that sometimes."

Q about schools, can schools permit staff and pupils to wear face coverings?

CMA: "it's not really a science question, it seems to me that that's a straight policy question and one for the schools, I mean there's nothing scientifically to say don't wear a face masks..."

"there is a problem, an important one, its not practical or sensible to ask small children to wear a face mask, the evidence in terms of the role of children in terms of their low role in transmission, suggests that would not be a sensible route to go down"

CMA: "prolonged use [of masks] indoors for routine workers is very difficult and that comes with all sorts of problems" @simondolan

CMA: behaviour change in period before lockdown when people were advised not to go to pubs etc 'was extreme'

Q now about @MLevitt_NP2013's work on epidemic curves following Gompertz

CMA: we didn't get anywhere close to that. so no is the answer

(he seems irked)...

Questioner - so no you weren't aware of the work, or you didn't take it into account?

CMA: no we did not consider that we were anywhere close to this moving to a non-exponential curve at that moment, and the modellers look at all these things all the time and give info on it...

... in order to do that you need to be much higher up the epidemic curve before you start to level off. We were nowhere near that.

CMA: it's probable we will see more waves at many points over the coming years.

"I don't think schools are going to trigger a second wave"

Schools are relatively lower risk than other things, we absolutely know there are risks to keeping schools shut

@sjblakemore

Reopening schools is priority, mental and physical health problems with keeping schools shut, and... children are at lower risk, and actually teachers are more at risk from other adults than from the children"

( @GOVUK announce no restrictions to schools reopening in Sept now?)

Q about working from home

CMA: Myself and SAGE, distancing measures are important, and of the measures working from home, for many companies, remains a perfectly good option, because it's easy to do, [may not be] detrimental to productivity

Q: economic impact is relevant to lives and health Is it right that that should not be part of SAGE, SAGE should just look at as it were transmission, and not look at some of the consequences of some of the measures?

CMA: "so we do look at the health impact of lockdown...

..."but we're not modelling that. We can't, because we don't have the economic modelling, but that is integrated at a cabinet office level, which always includes CMO [and/or] me, to make sure the epidemiology is properly understood in relation to business&economic decisions"

Q about care homes, CMA very quick to curtly point out SAGE gives advice and that the responsibility for actions taken in care homes lies with @DHSCgovuk

CMA @uksciencechief says there's a paper by the National Statisticians in the public domain with SAGE docs on the impact of lockdown on health - @AlistairHaimes?

(Sorry, by CMA I should have been typing CSA (Chief Scientific Adviser, Patrick Vallance @uksciencechief))

Q about R being misleading at low numbers.

CSA: early on was the right thing to measure, it's not the right thing to be using now.

Q about treatments and vaccines:

CSA: Remdesivir&Dexamethasone being used. New drugs coming along designed for this virus, rather than the above which were designed for other viruses. These may have bigger effect. In winter as many patients as possible needed for clinical trials

CSA on vaccines:

Over 100 projects across the world, Oxford vaccine in front at the moment, in phase 3 with thousands of patients. UK has a wide range of vaccine options because we don't know which one will win.

Q now on challenge trials, giving young volunteers who are vaccinated COVID to speed up trials.

CSA: challenge trials are well established. There are 2 challenges with this virus; dose, and rescue. Challenge trials need info about what dose causes a safe infection...

... and can you rescue it if you get it wrong.

Q and what's the current answer?

CSA: we don't know the dose, and we don't yet know that remdesivir will rescue the infection.

CSA: on vaccines, important to recognise the chances of having a totally sterilising vaccine, are low, much more likely to have a vaccine that reduces severity, and spread a bit...

CSA: Major public health campaign needed this autumn.

Q - also need one for flu?

CSA: we flagged up a long time ago that this needed to be a big flu vaccine programme [autumn], @DHSCgovuk understood.

Q about PCR testing @AlistairHaimes

CSA: PCR is very accurate, but that doesn't mean the test is very accurate, we know that you get false negatives &those false negatives can be quite high at certain times of the infection process, there are three main reasons for false neg...

... one is it's early in the infection and the person isn't shedding enough virus to be detected, second, swab hasn't be done properly, or third the PCR's a false negative for some reason. Swabs and timing are really important.

Q in winter, symptoms could be COVID or flu, they need t be tested, 350K people a day may need tests. Do we have capacity?

CSA: at the moment, no. I believe a plan is being developed.

CSA: as an adviser and at SAGE, I can't make that happen. I don't think anyone's in any doubt that getting the test right is important.

Q on modelling of number of cases and whether NHS capacity would be swamped. Have SAGE looked at this for the winter?

CSA: we're working on it at the moment. The Academy of Medical Sciences report made an assumption that the R would be 1.7, of course that is literally just...

... an assumption so we're just gonna go through that and work on it and make sure it's ready.

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