Rough calculations…

A stray bit of news this last week has significant implications:

A study led by the Pasteur Institute has found that just 4.4% of the  French population – or 2.8 million people – have been infected by the novel coronavirus, much higher than the official count of cases but too low to achieve so-called “herd immunity”.

“As of a consequence, our results show that, without a vaccine, the herd immunity alone will not be enough to avoid a second wave at the end of the lockdown. Efficient control measures must thus be upheld after May 11”, researchers say.

…

A Spanish study also published yesterday showed similar results, saying about 5% of the country’s population had contracted the disease and that there was no herd immunity in Spain.

But why control the situation? Because to let matters run uncontrolled runs, apart from the lethality of the virus, into two further problems.

Did a bit of number crunching on foot of figures released from NPHET at the weekend.

Over-85s account for 10.2 per cent of all cases, and 45.6 per cent of deaths, according to a breakdown of older age groups provided for the first time.
Out of a total of 22,915 cases, there were 771 among 65-69 year-olds, 910 among 70-74 year-olds, 974 among 75-79 year-olds, 1,241 among 80-84 year-olds and 2,329 among over 85-year-olds.
Out of 1,429 deaths, 69 occurred among 65-69 year-olds, 128 among 70-74 year-olds, 180 among 75-79 year-olds, 304 among 80-84 year-olds and 652 among over 85-year-olds.

1,429 deaths, 1333 aged 65 and over which leaves 96 aged below 65.

It’s back of the envelope stuff. But add a 0 to each figure below and rapidly those numbers ramp up. So, for example…

As of now we have…

22,915 cases
96 deaths below 65
1,333 deaths above 65
2,915 Hospital admissions
373 ICU admissions

Add a 0 as the virus spreads tenfold.

229,150 cases
960 deaths below 65
13,330 deaths above 65
29,150 Hospital admissions (NB there were 14,000 hospital beds in the ROI in 2017)
3,730 ICU admissions (NB Ireland currently has a total of 537 critical care beds)

Add another 0 – this would be approaching though not quite at half the population of the state. Still not enough though for ‘herd immunity’ in any meaning of the term.

2,291,500 cases
9,600 deaths below 65
133,300 deaths above 65
291,500 Hospital admissions
37,300 ICU admissions

Double that to bring the figures closer to the population of the state c20,000 deaths below the age of 65 and 266,600 deaths above the age of 65 A staggering near 583,000 people in hospital or thereabouts and 74,600 ICU admissions.

Would that happen? It would under the logic of those who have supported ‘herd immunity’. Could it happen in reality? Well, I think not for reasons articulated below. And there could and likely would be mitigating factors. Perhaps those who are hospitalised skews towards the elderly (though notably near enough 60% of those who died according to the figures released three days before the above figures were in a non-hospital environment).

As the virus goes through the population perhaps that would see that pool diminishing – which is a glib way of saying people would die in very very large numbers. That said the population of the state in 2016 over the age of 65 was 637,567 (in 2011 the number over 80 was around 130,598). That’s a lot of people and the first tenfold jump in the virus would easily be accommodated by that number – a jump that would have implications for the health service which are addressed below. Perhaps those with underlying conditions would be fewer as the virus worked its way through the population, perhaps some cocktail of treatments would be developed, though how would a health service under such pressure of numbers be able to use these treatments?

But cut it whatever way one wants once numbers ramp up we are talking appalling numbers of deaths, massive surges of people who have been infected, and consequent waves of those having to go to hospital and some on to ICU.

And keep in mind for the proponents of herd immunity those numbers don’t just have to ramp up, they have to keep going. They need to get to the point where everyone who can be infected is infected – despite there being no evidence as of yet that catching the coronavirus offers anything other than short term immunity from reinfection (as has been noted ad nauseam there’s no long term immunity against colds or flu). Kingston Mills in the IT pushed back hard against that particular concept of so-called “herd immunity” while noting that ‘A very optimistic figure of 60 per cent has been suggested as being the threshold for herd immunity against Covid-19, but this is not backed up by reproducible research findings’. So it would have to be more than 60%, though Mills argues for herd immunity through vaccination (or elimination or containment of the virus). But if the virus only reached 4-5% of the population in this initial outbreak(s) in Spain and France and we see the accompanying misery and death and attrition of resources in health and so on… what would it take to get to 60% plus?

And how would ICU deal with those numbers. Well ICU’s couldn’t, of course (George Lee does an interesting comparison with Sweden here on RTÉ taking the current levels of spread of the virus in both the ROI and Sweden. It’s not comforting either in relation to how matters might go if numbers ticked upwards). And hospitals would collapse. That would overwhelm any health system. Unless those who advocate the so-called “herd immunity” strategy are willing to stand over not admitting those cohorts in the 65 area to hospital care. Which likely would lead to even greater numbers of deaths and/or the breakdown of social and civil order as people revolted against governments who would carry through such a measure impacting on themselves or their loved ones. Or perhaps one lengthens the timescales. To absurd degrees.

As it happens David McWilliams did a not dissimilar exercise at the weekend here. 

Let’s assume that the current situation is sustainable, ie the daily new confirmed case numbers (265 as of 6th May, though it was more than 800 on certain days in April) won’t overwhelm the health system. Let’s also take the best-case scenario from Italy implying 10 per cent of the population have already had it. This means we can subtract 461,390 odd people from the total population.

Recall that the 75 per cent immunity threshold in Ireland equates to a total of 3,691,125 new infections minus that 461,390.

By any calculation, reaching that 75 per cent without a vaccine would take years. My worst case number crunching arrives at a figure of more than 30 years. Even the sunnier statistical estimates suggest that, without a vaccine, we could have 14 years of this “on/off economy”.

Fourteen years. McWilliams seeks answers in a vaccine. I’m not sure there’s any such answer to be had given the track record with other corona viruses. But either as a rapid or a slow process clearly allowing the spread of the virus is a non-starter.

Consider the collateral damage to the society as a whole and indeed the economic damage as well. Many people wouldn’t work in that sort of a context. It would be simply too dangerous and the chances too random. Factories would close, businesses would remain empty. Many many workers would be sick with the virus. Many would sustain chronic conditions of lungs, heart and other organs that would impinge significantly on their health and quality of life. Take by way of example those aforementioned meat plants where Covid has impacted hugely on their ability to function.

One worker in a plant who took ill and thankfully survived was in hospital for 49 days. He is unlikely to return to work for a year. Perhaps that’s an outlier. Perhaps those who fall sick won’t be in hospital that long or won’t be in hospital. But they won’t be at work either. And that has a profound effect in and of itself:

The company has since installed partitions between workers but has had to scale back production, processing 200 instead 400 pigs an hour, because so many staff were out sick.

Or consider this example of a Dundalk nursing home where 60% of the staff were out with the virus and the measures taken to keep it running were quite literally borne of desperation. There’s a single quote from the latter which points up the absurdity of the push to ‘work’ absent all other considerations:

“Overall, 60 per cent of our staff were unavailable for work, some of them ill or in isolation, others fearful for themselves or for a family member with underlying conditions.” Some managers were also unavailable.

Or this far from funny comparison between the precautions taken in the Dáil and those in meat plants. 

We hear the idea the ‘cure mustn’t be worse than the disease’ in relation to the lock-down. But in this case the spread of the disease itself would be so bad it would shred social and economic activity.

And of course there’s another term for ‘herd immunity’ as used by those who have believed the spread of the virus throughout populations is a feasible route – one that has the ugliest historical and political resonances, that being survival of the fittest. At base that is what ‘herd immunity’ means in this context.