Coronavirus: uncertainty and confusion

29/03/2020

You don't have to be a genius - or even the "brilliant" Neil Ferguson, whose computer modelling is taking a bit of stick - to work out where we could be going with Covid-19 epidemic.

Yesterday's burden of reported cases stands at 17,089 and if we make the conservative assumption that the numbers will double every five days, then by the end of the next fortnight we will be looking at 85,000 cases – not far short of the 92,472 being reported in Italy.

As for deaths, with 1019 reported yesterday (those who died in hospital) we could be looking at between 8-10,000 by the end of the fortnight, not far short of the 10,023 currently being reported in Italy, even if there is no guarantees that that figure is accurate, when local mayors suggest that the true death rate could be four times that posted.

In fact, we're not going to get accurate figures for a while yet – if at all – and we may have to rely on year-on-year comparisons, looking for a spike this year when compared with last year's figures – with adjustments which will keep the academics arguing for decades to come.

But, if we take the current Italian figures as a rough marker - against which to measure the UK performance in containing the epidemic – then if in a fortnight's time we weigh in with smaller numbers then we might take this as small sign that that the "lockdown", imposed last Monday, is beginning to have an effect.

Even then, the figures – as always – will need to be interpreted with care. We tend to use the words "epidemic" and "outbreak" interchangeably, but they are not actually the same. Technically, an epidemic is an incidence of communicable disease in excess of expectations so, in theory, since Covid-19 is a new illness and the expectation was zero, even one case could be regarded as an epidemic.

An outbreak, on the other hand, is two or more cases linked to a common source. This means that, as the epidemic has progressed, multiple sources have given rise to many different foci of infection, each becoming outbreaks in their own right.

Thus while we have one epidemic, we now have multiple outbreaks, each at a separate stage of development. The London outbreaks (probably in the plural) seem to be most advanced, which means that they will peak earliest and begin to decline.

By that time, however, we could be experiencing a ripple effect: as cases in some areas are on the decline, others might be increasing. And, as those in turn peak and start to decline, other areas may be experiencing rapid increases.

Thus, crude national figures may not give an accurate (or any indication) as to the effect of controls in specific areas (successes or failures), and it is only when we see a sustained downturn that we'll be able to say that the disease is in check – for the moment.

That, however, does not stop us experiencing a resurgence of the disease later on, and we could perhaps see a cyclical incidence, especially if acquired immunity is short-lived and/or the virus mutates, whence we could see a repeat performance of the last few months. And that state could continue until a vaccination is available in sufficient quantities to launch a national vaccination programme.

In the meantime, all we have to look forward to is uncertainty – and much confusion. For instance, on the one hand, we have Tom Pike of the Imperial College, London, playing with his models to tell us that the UK might get away with the surprisingly precise figure of just 5,700 deaths, on the assumption that social distancing will keep the daily toll of deaths below 250.

Given that yesterday's total was 260 deaths, and today's figure will almost certainly be higher – as we are recording the demise of people who may have acquired their infections more than two weeks ago – the chances are that we will be seeing steady daily increase for at least the next week, and high levels beyond that.

Clearly, Stephen Powis, the medical director of NHS England (pictured), hasn't got the memo. Answering questions via a video link during a coronavirus media briefing at Downing Street yesterday, he ventured the opinion (initially advanced by Imperial College) that, "If we can keep deaths below 20,000 we will have done very well in this epidemic".

Powis is confident that, if the overall figure is held below that level, we can stay within the NHS capacity, which is probably a reasonable assumption given that, in addition to the three emergency treatment centres being planned (in London, Birmingham and Manchester), one is being considered for Cardiff and, in all, some 13 venues around the UK may be used to give emergency treatment.

It is debatable, however, whether these centres will have as much effect as hoped. Reports indicate that, to date, patients in UK intensive care only have a 50 percent survival rate.

In the new centres, there will undoubtedly be a dilution in the standards of care – this much is anticipated – in which case the survival rate might be even lower. This is leading to suggestions that much of the effort being expended will be wasted. "The truth is", one doctor says, "that quite a lot of these individuals [in critical care] are going to die anyway and there is a fear that we are just ventilating them for the sake of it, for the sake of doing something for them".

This rather puts into perspective the comments of deputy chief medical officer who declared that, although WHO recommends testing (and tracing), it is advising all countries including low and middle income countries. But, for Britain, this is "not appropriate". She says:

We have an extremely well-developed public health system in this country … when you come to the UK, we have made it very, very clear that there has been a plan right the way through this which is entirely consistent with the science and epidemiology. We started with a containment phase and every early case of this disease was followed through, every contact was traced exactly as we would do for other diseases … but there comes a point in a pandemic where that is not an appropriate intervention and that is the point really where we moved into delay and, although we still do do some contact tracing and testing … that is not an appropriate mechanism as we go forward. At that point, what we need to do is focus on the clinical management [of new patients].

The point is, of course, that if "clinical management" is only partially effectively, then it is hardly appropriate to rely in this. The emphasis on prevention must surely take precedence.

This, therefore, simply adds to the confusion, especially as The Lancet has condemned the government's handling of Covid-19 as "a national scandal", stating that [the] "basic principles of public health and infectious disease control were ignored, for reasons that remain opaque".

The article goes on to say that the UK "now has a new plan: suppress; shield; treat; palliate. But this plan, agreed far too late in the course of the outbreak, has left the NHS wholly unprepared for the surge of severely and critically ill patients that will soon come".

Nevertheless, the government is sticking to its story, with Yvonne Doyle, Medical Director, Public Health England, giving oral evidence to the Health and Social Care Committee last Thursday (26 March), claiming that, from mid to late January until the middle of March, the strategy was one of test and trace.

At a point before we stopped that intensive contact tracing, she says, "it became clear to us that there were what I call dead ends of contacts where you had a case, you tried to find the contact, and it just was not possible, because that gave us the indication that there was sustained community transmission". There was, she also said, "limited capacity in the field service to contact hundreds of thousands of people".

What she doesn't say, however, is quite how limited that "field service" actually is, with the latest Public Health England report identifying a total staff resource of 2,093 (with a budget of £86.9 million) dedicated to "protection from infectious diseases". That includes operating national centres, regional network and maintaining the capability to identify infectious disease, its surveillance and the management of outbreaks.

The report does not identify the specific number of field staff dedicated to contact tracing but, in the nine regional centres, it is probably substantially less than 1,000 – the entire front-line, national capability available to deal with this Covid-19 epidemic.

An article in Zeit has Doyle complaining that there was "a lack of staff" to deal with the epidemic, but that is not the real problem.

No government is ever going to maintain thousands of professional staff, sitting idle on the off-chance that a major epidemic will come along – any more than it will keep a vast standing army to protect us in the event of war. As with the army, we need a core service capable of expanding very rapidly to deal with emergencies as they arise. This is not a staffing problem, per se, but a structural one, and one which the government seems rather keen to conceal.

Meanwhile, Mr Foot & Mouth says the lockdown will have to last until June if we are to avoid the worst effects of the epidemic unless, of course, Ferguson repeats his brilliant wheeze and has the government slaughter all coronavirus contacts – which is what it seems to be doing anyway, albeit by default. Never mind, the "British spirit" will see us though, says Johnson – those who survive.