COVID-19 – a bit of perspective: update

An update

According to ONS, in the week up to Sept 11th, there were 9,215 deaths from all causes in England. Of these, COVID-19 accounted for 97 deaths – that is about 1% of the total. Of course, we would expect that figure to rise as the number of cases increases. For the whole period of the epidemic (up to Sept 11), COVID deaths (52,482) account for about 12% of the total number of deaths (434,618) in England and Wales..

If we assume a case fatality rate (the number of deaths as a percentage of the number of cases) of 1%, this means that just under 9% of the population have been infected.  But we don’t know the case fatality rate for sure; I have seen estimates that put it as low as 0.3%. If that is true, then the number who have been infected (England and Wales) would be as high as 17.5 million, or 29% of the population.  That would mean, given the highly uneven spread of cases, that there would be some areas that would, at some point during the ‘second wave’, approach the level required for herd immunity to kick in (usually taken as about 60%).

Jeremy Dale 25/9/20

COVID-19 – a bit of perspective

Every death is a tragedy for those affected. Especially so for COVID, where someone may die in isolation, unable to see, or be seen by,  their loved ones. In no sense do I want to diminish that – and if you have been affected by the virus you may not want to read on. But in the midst of all the publicity about COVID, I feel it is necessary to try to put it into perspective.

First of all, let’s look at the data for COVID deaths. This is very confusing. The Government dashboard (1 August) puts it at 46,193 in the UK. This is the number who have died having had a positive test result. This has been much criticised, as it would seem to mean that even if you get run over by the proverbial bus, having been tested positive months ago, you are still counted as a COVID-related death. On the other hand, if you die from COVID but have never been tested (or the test didn’t work), you wouldn’t be counted.

If you look at the data from the Office of National Statistics (ONS), you get a different figure,  50.800, in England and Wales only. This comes from death certificates, and is the number of times COVID was mentioned (even if other causes such as pneumonia were also mentioned). I’ll stick with the ONS figure, mainly because I want to compare it with other data from ONS.

So, 50,000 deaths. That’s a lot of tragedies. But death is a part of life. During the period of the epidemic, 245,000 people have died from all causes – so that’s getting on for 200,000 people have died from something other than COVID. And during each of the last five weeks, more people have died from what is recorded as Influenza/pneumonia than from COVID.

Another way of looking at the impact of COVID is to consider the excess deaths – that is the number of people who have died from any cause, compared to the average number who died in the same period over the last five years. This shows that since the epidemic started there have been over 53,000 excess deaths. That measure includes the possible indirect effects of COVID, e.g., people who didn’t get appropriate treatment in time. If we look at the weekly breakdown of excess deaths, we see that during the last five weeks it has been negative – that is, fewer people are dying than expected. The likely reason for this is that one effect of COVID has been to cause the death of some people who would otherwise have died soon anyway.

Historical comparisons

The current crisis has highlighted the fact that we are no longer used to people dying in large numbers from infective diseases. Medical advances, including antibiotics and vaccines, coupled with improvements in nutrition, housing, public health and other environmental issues, have in general made such diseases of historic interest only, at least in countries like the UK. (This is not of course true for most of the world, where diseases such as malaria and tuberculosis are causing death and suffering on a large scale – in low income countries, communicable diseases represent 5 of the top 10 causes of death).

A look at the death statistics (from ONS) for 100 years ago (1915) illustrates the point. In that year, there were 66k deaths from pneumonia/bronchitis and 39k deaths from tuberculosis. We can add others – 13k deaths from measles. 5k each from diphtheria and flu (not an epidemic year), 4k from whooping cough and nearly 2k from scarlet fever.

In the more distant past, there are numerous examples of devastating infections. The Black Death (1381) is thought to have killed a third of the population. In the nineteenth century, there were repeated epidemics of cholera, with tens of thousands of deaths, and tuberculosis was rampant (at its height, causing a third of all deaths).

In more recent times, the best comparison is with pandemics of influenza. (Technical note: Influenza viruses are classified by their H and A antigens, the most common type being H1N1. Various H1N1 strains are similar but not identical in both, so you get a degree of cross-immunity, while another type say H2N2 differs in both and there is no cross-immunity between them. Major pandemics usually occur with a virus that has ‘shifted’ to different H and N types)

In 1957-58 there was a pandemic of so-called ‘Asian flu’ (H2N2), which caused some 20-30k deaths in the UK. Then in 1968-69, we had an H3N2 strain (labelled ‘Hong Kong’ flu) for which the estimates of the number of UK deaths go up to 80k. In neither case was the official response anything like what we are currently seeing with COVID-19. And the media managed to find plenty of other news to cover.

More recently, there was some concern about ‘swine flu’ (2009). The incidence rose to about 110k cases per week in July, before dropping off, and then re-emerging in the autumn to about 84k cases per week in October. However, mortality was low (<1,000 deaths in UK), probably because this was an H1N1 strain, and older people had already encountered H1N1 strains and so had significant immunity to it.

Why all the fuss?

Why is it that fifty years ago we could face a disease that caused up to 80k deaths, not exactly with equanimity but at least without the massive sacrifices that we are currently making for a disease of (apparently) similar magnitude? Of course, we have to recognise that without the control measures it might have been much worse. Based on what was known about the disease, the initial assessment was that, if left unchecked, the disease would spread until Herd Immunity was achieved, and that would happen when about 60% of the population had been infected. Assuming a case fatality rate of 1%, that implied something like 350,000 deaths, which was deemed unacceptable. Of course we will never know if that would have happened, but a comparison with other countries is interesting. We hear a lot about the numbers of deaths in the USA and Brazil, but if we look at the numbers of deaths per million population, we are still some way ahead of either of them (UK 680, USA 477, Brazil 440) – although I am well aware of the dangers of reading too much into such comparisons, given the different methods and reliability of reporting deaths. But superficially, it could mean that our lockdown didn’t have much effect, and the original estimate of 350,000 deaths was over the top.

I’m not saying that we should all ignore the advice, and go out and party. But let’s keep a sense of perspective. At the individual level, unless you are in an extremely vulnerable category, there are plenty of other ways of dying that we don’t bother too much about. But collectively, we still have a duty to try to limit transmission so as to protect those who are more vulnerable. Above all, don’t panic!

Jeremy Dale

2 August 2020

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s