Coronavirus - worldwide spread and control

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Thought y’all might be interested in this analysis of Irish cases. Smaller numbers and earlier stage of the pandemic than some other European countries. Bit of context first:

Population is approx. 5 million.

Ireland had its first case confirmed 29th February. (Compare to UK end January.)

Schools were closed in Ireland from 13th March, at which point 70 cases had been confirmed.

(Compare to UK where a BBC report 14th March reported 1410 confirmed cases.)

Ireland has 557 confirmed cases as of Wed 19 March. Testing is being ramped up, so as well as the spread itself increasing, Ireland’s numbers are expected to increase quite a lot.

This analysis is of the first 350 confirmed cases:

https://www.gov.ie/en/publication/c...at-as-of-midnight-tuesday-17-march-350-cases/


Median age of Irish cases to 17th March is 43.

Compare to median age of 63 in Italy in @Simon M ’s post above, although the median age of Irish cases could increase as testing and spread etc increases.

2004 cases, mostly from Northern Italy
355 deaths
Document dated 17 March 2020 (but I think this is only 10% of total deaths)

Median age at diagnosis: 63
Median age at death: 81

Compare also to the Chinese data:

The median age of all patients was 57 years old, which is close to the data reported by Wang et al3 (56.0 years) and Chen et al1 (55.5 years), but older than that reported by Huang et al2 (49.0 years)…

Median age was 64 years in severe cases, compared to 51.5 years in nonsevere cases

https://onlinelibrary.wiley.com/doi/full/10.1111/all.14238

It seems possible that the median age of cases increases as the virus spreads through the community. The younger, more mobile people might be the first to get it and then it gradually makes its way to the older ones?

31% of the 350 Irish cases were hospitalised and the stats show that more older patients were hospitalised.

2% were admitted to ICU.

There have been 3 deaths.

No information on co-morbidities unfortunately. My understanding is that the first two deaths did have other illnesses, and the third fatality did not.

There was a big jump in confirmed cases between March 18th (74 new cases) and March 19th (191 new cases).

More on how covid-19 has evolved in Ireland here:

https://www.irishtimes.com/news/health/coronavirus-how-it-has-affected-ireland-day-by-day-1.4206691
 
I think there are some fundamental misunderstandings regarding "herd immunity" being propagated.

Although the Science Media Centre provides some good explanations about what it is (https://www.sciencemediacentre.org/expert-comments-about-herd-immunity/), very little is actually known about the dynamics of SARS-CoV2 precisely because it is a new virus.

The assumption that the epidemic will start to "burn out" at about 60% is just that, an assumption (based on what the likely R0 might be). It is also an assumption that reaching that point will convey lasting "herd immunity" or anything like it. Herd immunity is usually reached after vaccination programmes, because vaccination can often confer much better and longer-lasting host immunity than exposure and recovery from the virus itself (this is particularly true in the case of measles, and we are only just beginning to learn why that is the case). But it also requires constant maintenance to keep levels of protection up. That's why we have vaccination programmes to make sure that new entrants into the population are covered. If immunity to SARS-CoV2 wanes after a few months in some people, any protective herd immunity could easily drop below the required level and the epidemic start up again. This is how virus infections either establish seasonality or even become endemic.

So when talking about "herd immunity", be aware that it is something that it is likely to be transient, it may not even be achievable at all, and it is unlikely to be desirable to achieve, given the mortality/morbidity associated with COVID19.
It's a very bad situation that in the UK the concept of 'herd immunity' has been seeded in the minds of the public. Reading through comments on news sites, such as the BBC (a depressing reading at the best of times) it's very clear that many people still (as of today, days after the U-turn on this approach) believe that the government should have kept to that 'original plan' and that we are now over-reacting and needlessly sacrificing the economy.
 
I think there are some fundamental misunderstandings regarding "herd immunity" being propagated.

Although the Science Media Centre provides some good explanations about what it is (https://www.sciencemediacentre.org/expert-comments-about-herd-immunity/), very little is actually known about the dynamics of SARS-CoV2 precisely because it is a new virus.

The assumption that the epidemic will start to "burn out" at about 60% is just that, an assumption (based on what the likely R0 might be). It is also an assumption that reaching that point will convey lasting "herd immunity" or anything like it. Herd immunity is usually reached after vaccination programmes, because vaccination can often confer much better and longer-lasting host immunity than exposure and recovery from the virus itself (this is particularly true in the case of measles, and we are only just beginning to learn why that is the case). But it also requires constant maintenance to keep levels of protection up. That's why we have vaccination programmes to make sure that new entrants into the population are covered. If immunity to SARS-CoV2 wanes after a few months in some people, any protective herd immunity could easily drop below the required level and the epidemic start up again. This is how virus infections either establish seasonality or even become endemic.

So when talking about "herd immunity", be aware that it is something that it is likely to be transient, it may not even be achievable at all, and it is unlikely to be desirable to achieve, given the mortality/morbidity associated with COVID19.
I am wondering what the implications of this might be. Secondary infection is possible for some people, but tends to be pretty mild. That is good for the individuals concerned but not good for the herd immunity and those people are also likely to spread the illness to those not yet exposed.



Does that mean such people would need quarantining again, and would that be possible with a mild infection which might be hard to spot or may even be a symptomatic?



Does it mean everyone has to hunker down until there is a vaccine or good treatments?



I would love to know how it's going in China as they relax controls. Not that there's much chance that the UK government would want to follow good practice elsewhere, judging by events so far.
 
In London they shut lots of tube stations from today. Except now everyone is getting on at the few stations that are still running. Because they’re forced to go to work as there’s no provisions for proper sick pay / citizens income etc, and many could lose their jobs otherwise. I really despair.



Palliative care doctor:

 
How will age distribution in populations affect how covid-19 spreads and impacts different countries? If Italy's high death rate is due to its older population, then will countries with younger populations fare better, at least in terms of fatalities? Or will younger people spread it so effectively, while asymptomatic or mild, that...I don't know how to finish that sentence.

Median age of Irish cases to 17th March is 43.

Compare to median age of 63 in Italy in @Simon M ’s post above, although the median age of Irish cases could increase as testing and spread etc increases.

The difference in median age of covid-19 cases between Italy (63) and Ireland (43, but very preliminary data) could have a lot to do with the difference in median age between those countries’ populations. Italy’s population is unusually old, and Ireland’s is unusually young.

According to an EU commission report in 2010:

As of 2010, the oldest populations are in Germany and Italy, with median ages respectively 44.2 and 43.1; the youngest by far in Ireland with 34.3.

Germany had the largest proportion of those aged 65 or over, 20.7 per cent, followed by Italy, 20.2 per cent. The lowest proportion of those aged 65 or over was in Ireland (11.3 per cent), Slovakia (12.3 per cent) and Cyprus (13.1 per cent).

https://www.irishtimes.com/news/study-says-ireland-has-youngest-population-in-eu-1.561163

Median age in the UK is 40.5, says Google.

Germany's death rate is apparently low, though, so far, despite its older population:
experts warn against drawing sweeping conclusions. They argue that the country’s low fatality rate most likely reflects the fact that the outbreak is still at a relatively early stage, and that the age profile of those affected has so far been younger than that in other countries. https://www.ft.com/content/c0755b30-69bb-11ea-800d-da70cff6e4d3

I’m too wrecked to see anything useful in these age pyramids for Italy, the UK & Ireland, but here they are, for clearer minds (all from Google):

Italy:
Population_pyramid_of_Italy_2016.png


UK:

resource


Ireland:
ireland-population-pyramid-2018.jpg
 
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Although the Science Media Centre provides some good explanations about what it is (https://www.sciencemediacentre.org/expert-comments-about-herd-immunity/), very little is actually known about the dynamics of SARS-CoV2 precisely because it is a new virus.
Hate to promote the SMC but some good comments on there.

Prof Willem van Schaik, Professor of Microbiology and Infection, University of Birmingham, said:
Clearly the government believes that this process is manageable and building up herd immunity is the most effective way to stem Covid-19. I note that the UK is the only country in Europe that is following this strategy. Other countries also use scientific advice to guide their research and it is unclear to me why the UK is alone in their laissez-faire attitude to the virus. Perhaps the government has access to modelling data that suggests that the numbers I quoted above in numbers of cases and deaths are unavoidable in any scenario (e.g. even with prolonged social distancing strategies) but unfortunately these data, if they exist, have not been made available to the wider academic community so it is difficult to comment.
This puzzles and concerns me too. Why did the UK Government adopt a different strategy to the rest of the world? Did it have access to different modelling data that it believed justified taking a different approach? If so, why did it not share this data with the rest of the work to try to save lives in other countries? Or was it that the UK Government was seeking to achieve different objectives to rest of the world – perhaps, placing a higher degree of importance on minimising the economic impact rather than minimising mortality rates compared with other countries. Whatever the reason, it does not reflect well on the UK Government.
 
Or was it that the UK Government was seeking to achieve different objectives to rest of the world – perhaps, placing a higher degree of importance on minimising the economic impact rather than minimising mortality rates compared with other countries.
I wouldn't be surprised if the thinking was along the lines of "if we can avoid a major shutdown, then our economy will be in a much better shape once most people are back at work and we'll then be ahead of the curve". Add in a belief in the ability to build herd immunity in a sustainable way, and you get the situation we were in.
 
Thanks @Roy S I didn't access the material as you needed to agree to a bunch of stuff. Anyone got the statistics for fatalities in men versus women?

There are several figures and other preliminary info and speculations.
I can't summarize it well.
I'm sure the subject will be covered more as time passes.
 
Cornwall has asked people not to take holidays in the area:

The leader of Cornwall council, Julian German, and the Cornish MP Steve Double have asked people not to travel to the far south west of England.

Politicians and doctors fear an influx of people to Cornwall from London and other cities could put pressure on the health service in the area – and spread the virus.

In an open letter they said:

It is important that everyone follows the advice laid out by the government to slow and stop the spread of this virus and do everything we can to support our essential public services, especially our NHS.

That includes avoiding non-essential travel.By anyone’s assessment a holiday at this time is not essential. So therefore, regrettably we are asking people not to come on holiday to Cornwall at this time.

We need to stop the spread of this virus and also need to protect our NHS and keep our supermarket shelves stocked. An influx of thousands of tourists in the coming weeks will put unnecessary pressure on our services.

As a supporter of the tourism and hospitality industry we fully understand the huge and grave challenges facing the sector at this time and why some businesses may want to take this opportunity to bring visitors to Cornwall.

However, this is first and foremost a medical and health crisis. We must not underestimate how serious this is and our first priority has to be to protect the public from this dangerous virus.

Please take all the appropriate steps to keep you and your family safe, and help Cornwall stay safe and well by avoid coming here on holiday at this time.”
 
The UK government has just published the papers that have been informing it's decisions:

https://www.gov.uk/government/news/...vidence-supporting-the-uk-government-response

Guess which group they fail to link to further information on?

SAGE relies on external science advice, including advice from expert groups and their papers. In the case of COVID-19, this includes the New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG), Scientific Pandemic Influenza Group on Modelling (SPI-M) in the Department for Health and Social Care, and the Independent Scientific Pandemic Influenza Group on Behaviours (SPI-B).
 
I’m having some painting done on the outside of my house on Monday. Stood on the drive talking to the painter he’s able to do it then due to indoor jobs being cancelled. Thinks it might blow over in a couple of weeks. I felt unable to let it go so I pointed out we are 2 weeks behind Italy on the same trajectory. A lot of folks just aren’t getting the message unfortunately. Messaging is simply not strong enough from the government. Had to rein myself back from commenting directly to some relatives on Social média about their lack of social distancing. But I have made my own post saying don’t go to pubs etc. Hopefully they will realise this means them.
 
There's this on the govt's behavioural advice:

https://assets.publishing.service.g...oural-science-in-the-coronavirus-outbreak.pdf

With respect to issues around self-isolation and quarantine, two papers based on the same underlying rapid evidence review have been particularly drawn on [3,4].

3. Brooks SK, Webster RK, Smith LE, Woodland L, Wessely S, Greenberg N, Rubin GJ. The psychological impact of quarantine and how to reduce it: Rapid review of the evidence. Lancet 2020; 395: 912-920.
4. Webster RK, Brooks SK, Smith LE, Woodland L, Wessely S, Rubin GJ. How to improve adherence to quarantine: Rapid review of the evidence. Public Health, in press.

Only the first paper is public yet, and I didn't see much of value in there.

This article I already posted mention how there wasn't really any info in their to justify delaying social distancing measures, or concern about behavioural fatigue undermining social distancing measures at some vital point:

The evidence that emerged was surprising. On Friday, one of the government’s advisors explained that the idea of social fatigue, which was used as a rationale to delay quarantine, was based on a literature review of the psychological impacts of quarantine.

But crucially, the literature review made no mention or recommendations of how early quarantines should be implemented. It also stated explicitly that only a few of the papers it included directly compared quarantined versus unquarantined patients, which makes it difficult to establish whether quarantine would cause more panic and social fatigue in an epidemic than the absence of quarantine.

https://unherd.com/2020/03/the-scientific-case-against-herd-immunity/

I want to see what led to the view that behavioural fatigue meant that social distancing measures should be delayed. Was Wessely privately hyping his own work again?
 
A lot of folks just aren’t getting the message unfortunately.

I don't think folk do get it. But because [some people] have warned the govt against scaring people too much, they seem to be much more worried about causing PTSD than they are about people actually dying. Human beings are not good at assessing risk, and sometimes we just need to be shouted at to get us to act. All this "would you mind awfully" is not terribly effective!
 
It's a very bad situation that in the UK the concept of 'herd immunity' has been seeded in the minds of the public. Reading through comments on news sites, such as the BBC (a depressing reading at the best of times) it's very clear that many people still (as of today, days after the U-turn on this approach) believe that the government should have kept to that 'original plan' and that we are now over-reacting and needlessly sacrificing the economy.
It's a bit like a massive invading army marching its way towards you, but as yet you have only so far encountered small platoons of their advance forces. Instead of heeding what your own scouts are telling you - that a massive invasion is following on behind, and you absolutely must prepare before it is too late - you instead choose to believe what you want to believe. By the time you have no choice but to believe the reality, it is far, far too late.
 
Sorry for making lots of quick posts while I look through this - I'm keen to get other people's ideas.

I still cant find the evidence under pinning their concerns about fatigue but they are hyping themselves for their transparency: "In fast moving situations, transparency should be at the heart of what the government does." https://www.gov.uk/government/news/...vidence-supporting-the-uk-government-response

This is their behavioural advice from 9th March, but I couldn't see anything on fatigue or the advantages of delay:

https://assets.publishing.service.g...ventions-on-an-epidemic-of-covid-19-in-uk.pdf

This 16th March consensus seems thin to me too considering their talk of the need for transparency:

https://assets.publishing.service.g...w-on-behavioural-and-social-interventions.pdf

Still of interest though, eg:

It was agreed that the addition of both general social distancing and school closures to case isolation, household isolation and social distancing of vulnerable groups would be likely to control the epidemic when kept in place for a long period. SPI-M-O agreed that this strategy should be followed as soon as practical, at least in the first instance

4.It was agreed that a policy of alternating between periods of more and less strict social distancing measures couldplausiblybe effective at keeping the number of critical care cases within capacity. These would need to be in place for at least most of a year. Under such as policy, at least half of the year would be spent under the stricter social distancing measures.
 
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