Am going to talk about my experience with media bias around discussions of zero COVID & how this is shaping our COVID strategy. I've encountered this again & again. Am also going to speak about why it's important we consider elimination from an evidence based perspective. Thread.
Yesterday I was contacted by a prominent BBC programme to speak about strategy for exit from lockdown & the role of scientists & politicians in defining this. I outlined elimination as a preferred strategy and provided factual arguments to support this on being challenged.
I was told this was 'interesting', but later told me the programme had moved in a different direction (not on zero covid). This has happened to me before. I watched the show- it was clear that the same issues were discussed *except* elimination was not considered at all.
I know the direction was the same also because the same person from govt who I was supposed to 'debate' with was on the programme too, but just debating with a different expert. This wasn't the first time this had happened with the same programme.
I did another (different) interview on the BBC last night, where I was told that elimination was not a possible option by the presenter - and similarly challenged about this again by a presenter on the LBC this morning. I will address the arguments around this later in the thread
There is media bias around discussing an elimination strategy- which is considered 'unrealistic' or not possible in the UK- where the rhetoric from govt & its advisors has been 'acceptable deaths' or 'living with it'. And this is hugely impacting conversations around UK strategy
These ideas are prominently platformed and discussed on the media, and discussions around elimination tend to be shut down. This is despite world-leading scientists, including @IndependentSage having repeatedly advocated for this approach, and this approach being tried & tested.
So let's have the discussion I was hoping to have yesterday on long-term strategy for COVID-19 in the UK. As I see it, there are two routes (not mutually exclusive).
1. Elimination through multi-pronged measures
2. Immunity through vaccination - accept 'tolerable' cases & deaths
Let's look at each of these. Let's look at 1. first - this strategy would require restrictions to be in place to bring cases down to very low levels (<10/100K) before easing restrictions. During this period, we would need to reform our broken Test, trace, isolate & support system
Duration of restrictions? From current levels, at an R=0.8, it would take 2-3 mnths to reach this target. If we improve current measures (better support for isolation, improved masking policies, mitigation in schools), this period could be reduced significantly, by reducing R.
What do we need to do during this period? Need to fix our test, trace, isolate system (put it in the hands of the NHS where its performance for complex cases has been excellent). Support with isolation. Improve safety measures in schools. Managed quarantine for 14 days at borders
Once we come out of lockdown, our test, trace & isolate system will need to rapidly identify any cases that arise, and take urgent measures to trace contacts, isolate, and stop spread into the community.
Additional protections e.g. mask use, distancing in some settings will continue until we have no outbreaks for a period of time, when life can return to normal. We will continue vaccinating people so they are protected in case community transmission occurs.
We will need continued border quarantine restrictions, like NZ & Australia which have been quite effective in preventing re-introduction of infection. When this does occur, it will need a quick & aggressive response.
This approach is associated with generally lower uncertainty because:
1. We've seen this be achieved in other countries.
2. It will require a defined duration of measures, but life will return to near-normal.
3. Less uncertainty around vaccine strategy
e.g. we wouldn't have to consider deviations from vaccine protocol, as vaccines are a pre-emptive measure, rather than carrying out vaccine roll-out in the midst of an overwhelmed health system.
4. Less uncertainty around evolution of new variants, and impact on vaccine efficacy
Let's look at 2. now - trying to achieve herd immunity or at least less severe illness in the majority of the population through vaccination.

While vaccines are central to any pandemic strategy, there are many unknowns with an approach that focuses solely or mostly on vaccines.
1. While vaccines confer protection against severe disease, & symptomatic infection, we don't know the extent to which they reduce transmission.
2. Even with full uptake of vaccines in eligible (not trialled in children yet), no guarantee of reaching the herd immunity threshold
3. The virus may be a moving target with the rapid evolution we are seeing at the moment, with mutations that make vaccines less effective, at least in preventing symptomatic infection. This means we may never reach elimination with vaccines.
4. Even without escape mutations, just with more transmissible strains, the herd immunity threshold (the proportion of the population that needs to be vaccinated to bring R below 1) will be higher. More transmissible new variants could push this even further.
5. We don't know the duration of immunity conferred by vaccination, which may mean frequent boosters are needed to top this up, or against new variants - we will need a high uptake of these across the population
6. We don't know the impact of vaccination in preventing long COVID
7. There is significant vaccine hesitancy in groups who are most at risk for many legitimate reasons, including structural discrimination which is not just historic but has continued throughout the pandemic. While uptake has been high in vulnerable groups, this may not generalise
Worth remembering Manaus where the majority of the population was exposed to virus, but we are still seeing surges of cases that are overwhelming healthcare capacity, with R well above 1. This could be the impact of a new variant escaping immune responses to previous variants
Or it could mean a higher herd immunity threshold than we anticipated, or that the duration of immunity conferred by infection is lower than we previously thought. Either way, it's clear that achieving elimination through this approach may not be as straightforward as we think.
Even if we could achieve herd immunity through vaccination, what is the cost of transmission after easing lockdown going to be, while only part of the population (albeit some of the most vulnerable) are vaccinated?

While it may seem counterintuitive, the cost is still huge.
A SAGE/Imperial model which examined release of restrictions gradually from March alongside vaccine roll out showed that even in the most optimistic scenario, this could lead to between 82,000 and 150,000 deaths. Model here:
assets.publishing.service.gov.uk/government/upl…
How is this possible?
Many reasons.
1. A single dose of vaccines in the over 70s will not provide absolute protection even for them.
2. Many deaths occur in people under 70 yrs
3. Roll-out and immunity post-roll out take time to develop
Exponential rises in cases can rapidly lead to high numbers of deaths even while vaccine roll-out continues.

While the model focuses on deaths, the impact on long COVID numbers would also be large - given case numbers & transmission would be high.
Further, high levels of transmission continuing alongside vaccination mean greater potential for virus adaptation. Escape mutations have arisen in the UK, even when population-wide immunity wasn't at high levels. With more selection pressure we should expect more adaptation.
We currently have at least three different variants with the E484K escape mutation circulating within the UK. We've been told that these are not likely to become dominant any time soon- but if these escape vaccines better than the original B117, they may become more frequent.
While we may be able to update vaccines, this will take time, and as we've seen from the data, high levels of transmission even over short periods of time with a partially protected population can have huge consequences.
And there are no guarantees will we be able to keep up with virus evolution. It's possible by the time we have vaccines against these variants, more may have evolved, if we allow adaptation to continue (by allowing high levels of transmission to continue).
So what about the 'downsides' of elimination that we keep hearing about?

'But we will need to have travel restrictions indefinitely'

Response: But we have travel restrictions in place now - and will likely need them to be in place for a long time because of new variants.
Not least because we have new variants within the UK, that many countries across the world are worried about importing.

It is likely we will need strict managed quarantines, but we will likely need these even in scenario 2.

And we're an island, so in some ways easier
'We can't do this - the UK is a travel hub- we can't have restrictions for so long'
Response: We've been in restrictions and in an out of lockdowns for almost a year. This will be much shorter, and the long-term impact on the economy much lower - with greater long-term certainty.
'But population density!'
Many countries across the world with greater population density than ours have achieved this - Taiwan, Vietnam.

'But we're culturally different'
Australia, New Zealand?

'But it would never work'
Why? It's clearly worked in other parts of the world
I think we need an honest, transparent, and factual discussion about this in the UK. These options aren't mutually exclusive, but one provides much more certainty, is tried & tested & has many advantages.

We should at the very least consider it & not silence discussions on it.

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More from @dgurdasani1

14 Feb
Just an observation that while we're still debating mask use in schools in the UK, countries in Europe are revising policy on grade of masks in school (e.g. France on surgical or FFP2 grade masks in schools). Exceptionalism means we're constantly behind on evidence-driven policy.
In the UK, we've built ideologies around exceptionalism.

'Our children wouldn't tolerate masks' (despite millions of children around the world & in Europe wearing these - both in primary & secondary school settings - without any evidence of harm).
We live in an environment where we feel children are exceptional in that they aren't very susceptible to infection, or don't transmit much, and school environments are exceptional environments where significant transmission doesn't occur. These ideas are not grounded in evidence.
Read 5 tweets
12 Feb
This is irresponsible & negligent- we haven't learned anything from past mistakes. Letting a big wave of infection flow through the UK would mean hundreds of thousands of people with long COVID, and further virus adaptation & spread that may threaten vaccine effectiveness.
We can't count on being able to tweak vaccines to keep on top of virus adaptation- adaptation has happened much faster than we imagined- and is continuing in a way we can't predict. This is the same as the 'focused protection' & herd immunity strategy promoted by the GBD.
We've literally seen the impact of this strategy- which has given rise to more transmissible variants, and more recently variants with mutations that can potentially reduce vaccine effectiveness. We have exported these variants to much of Europe, with impact for pandemic response
Read 4 tweets
12 Feb
Worrying data from the most recent PHE surveillance yesterday - despite these data really underestimating infection in children (as they are based on symptom based testing), positivity rates appear highest in early year settings (fully open) & primary schools (20% attendanc).
The real differences are likely to be greater, given that much of infection is asymptomatic in children. Also worth noting the steep drop initially after school closure, which then plateaus to become more gradual after school re-openings.
Infection among children closely tracks school openings and closures (as we saw even during october half term), and level of attendance (trends in secondary schools where attendance is much lower are different). Again in line with substantial transmission occurring in schools.
Read 4 tweets
11 Feb
“If we let variants emerge, amid high transmission rates, that new variant could easily overtake the whole viral population,” @GuptaR_lab

Stark contrast to the rhetoric from JVT at the briefing earlier this week. We need to contain transmission urgently

theguardian.com/society/2021/f…
Let's remember that E484K has emerged on the background of the UK variant, not once, but many different times- this means that the virus is evolving in this direction. And if it's allowed to continue adapting, through high levels of transmission, it will continue to do so.
And as I've said before, as pressure from vaccine-acquired immunity mounts, we should expect the selection pressures on the virus to be different - it's entirely possible that if high transmission is allowed to continue alongside vaccination, this will create pressure for escape.
Read 5 tweets
10 Feb
The govts quarantine policy appears to be nothing but useless PR that's not grounded in any evidence. What is the point of a policy that allows those coming in from most countries to test and release from quarantine after 5 days?

theguardian.com/world/2021/feb…
SAGE and indieSAGE both advised that we will not be able to prevent import of new variants unless our quarantine policy is comprehensive, given how quickly variants spread between countries. Of course, the govt is still not 'following the science' -
even after we have new variants established within the community that could potentially threaten vaccine effectiveness. When are they going to start listening to experts?
Read 4 tweets
10 Feb
Documents from the 29/30th July released by the govt on the 5th of Feb where SAGE warns the govt about the risk of school transmission on the pandemic. The documents warn about outbreaks from schools spreading into the community. Why were these released 6 mnths after publication?
This document, & another one outlines the risk of increased transmission over winter, including a reasonable worst case scenario model carried out on the 29th July but only released on the 5th Feb. The predictions of this model have already been exceeded for hospitalisation peaks
The govt was clearly warned about the risk of a second wave of infections relating to winter, Christmas & school transmission. This advice seems to have been ignored, and not even communicated to the public until after the event. Why? This lack of transparency is very concerning.
Read 6 tweets

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