Essential reading for the day is a brief article in the Lancet
headed: "What policy makers need to know about COVID-19 protective immunity". Almost written at Janet & John level, it may be sufficient to inform some members of government, independently of their coteries of advisors, given that they can look outside their bubble long enough to absorb the detail.
But what particularly struck me was a short passage in the first column which emphasised the role of transmission in the aetiology of Covid-19. Without equivocation, it said with disarming simplicity, "stop transmission and you stop the virus".
This principle was immortalised by one of the pioneers of modern epidemiology, John Snow who, in 1854 traced the source of a cholera outbreak in Soho, London, to a public water pump. In the popular version of the narrative, by removing the pump handle, he brought the outbreak to an end.
We saw the same dynamic at play in May 1964 during the Aberdeen Typhoid Outbreak
where the investigators, with some little delay, identified the vehicle of infection as a can of corned beef, the contents of which had been sliced and sold from a local shop.
Closing the shop which had sold the meat eventually stopped that particular outbreak, but it did not address the original source of infection, ostensibly responsible for other (smaller) outbreaks of typhoid. That was traced to a canning factory at Rosario, Argentina.
At the factory, the chlorination plant had been out of action for a period of 15 months. With the water drawn directly from the polluted River Plate, it was hypothesised that typhoid bacilli in the water had been sucked into a can (or cans) through a microscopic pin-hole during the cooling process.
During a subsequent inquiry, it transpired that the Department of Health had known several months previously that there could be plenty of corned beef in Britain which had been processed under unsatisfactory conditions.
But, "In view of the fact that there was no pointer to any disease associated with meat from the plant", it was considered that "the recall of stocks held in the country was not justified". In measured terms, the committee of inquiry observed that, "There was no doubt that this decision had proved in retrospect to be a mistaken one".
The account of the outbreak, one of the largest of its kind – which I collated from the inquiry report and contemporary newspaper articles – gives a graphic feel for the pressures experienced during such an incident, right down to the investigators glued to the epidemic curve for signs that their control measures were working.
Of course, when dealing with this Covid-19 epidemic, control is far more difficult. The sources of infection are human beings and through the course of an epidemic, there may be thousands if not hundreds of thousands of such sources, attributed to not one but multiple outbreaks.
But while the job might be harder, the basic principles are the same. It involves the laborious process of testing symptomatic cases to confirm the presence of the infection, and enforcing their isolation until they are tested clear. It also requires tracking down the contacts of each case, again testing and isolating them until they are shown to be clear of any infection.
Those multiple activities all boil down to that one thing – breaking the chain of infection. It is almost fifty years since I sat in a dingy classroom in South-East London, being taught those principles as a student public health inspector. Little did I think that I would be revisiting them fifty years later, much less seeing them published in an article in the Lancet
, aimed directly at instructing policy-makers as they struggle to contain another, different outbreak.
Back in 1964, after the citizens of Aberdeen had had their lives so rudely disrupted (the city was effectively closed down, and it took a visit from the Queen to re-open it), it was instructive to see that one of the major agencies responsible for the outbreak – albeit by default – was the Department of Health.
Thus do we see history repeat itself – after a fashion. For sure, the Department cannot be blamed for this epidemic, but it has had a significant hand in the scale of the outbreak. Its first area of default was, directly and indirectly through its agencies, its failure to plan adequately for its eventuality. The second element has been its lack of flexibility in responding to changed circumstances, when it became evident that it had been planning for the wrong disease.
Thirdly, and perhaps most grievously, has been its determination to use the district general hospitals network for the primary response, for treating Covid-19 sufferers. This, on the one hand, has necessitated the treatment of highly infectious patients in unsuitable buildings which, by any sanguine measure, were not fit for purpose.
This has meant increased risks for staff, and has most definitely caused a number of episodes of cross-infection, giving rise to illness in patients admitted to hospital for reasons other than Covid-19, some of whom have died.
But the most cynical – and irresponsible – measure has been the wholesale clearing of beds in preparation for the "surge", turfing out infected patients to the charge of care homes which were ill-equipped to deal with them. Another side to this policy has been the refusal to accept ill patients from care homes, if it was judged that medical intervention would not assist them – thereby leaving under-trained and ill-equipped care home staff to pick up the pieces.
Now, though, the consequences of this policy are beginning to become apparent, with the Financial Times
reporting that overall coronavirus deaths are more than twice the official level of hospital deaths.
There are obvious caveats to these figures but it is nevertheless clear that great carnage has been occasioned in care homes, with the staff struggling with increased incidence and arguing that they, not the NHS, are now in the front line.
has been doing its own calculations on this issue and argues that the total excess deaths since the start of the Covid-19 epidemic stands at 47,000. Much of the increase, it says, has been recorded in care homes.
In the week to April 17, 7,316 deaths were recorded in these institutions, compared with an average of 2,154 for that week over the past five years. The fact, it adds, that excess deaths in care homes were 5,000 more than the long-term average in one week suggests the crisis in the care sector is even deeper than previously feared.
The Department of Health is responding by setting up mobile test centres, so that patients in outlying care homes can be properly diagnosed, and there have been some revisions of admissions criteria, which may mean more care home patients are sent to hospitals. And, to keep the issue in the public eye, daily figures for deaths in care homes are to be published.
None of these measures, though, will help care home residents who have already died from Covid-19 or are at death's door. Nor will it help care home staff who have been similarly stricken.
Putting all this together, and reaching back to the 1960s and the Aberdeen Typhoid Outbreak, one can conclude that, all too often, a major cause of morbidity and mortality in this country stems from the inadequacies of government – or governance, if you want to take in NHS executives, and agency officials.
Perhaps we need a new category of disease. To add to iatrogenic (diseases caused by doctors) and nosocomial (illness caused by hospitals), we should have a name for disease caused by official policy failures. The dog-Latin term "consiliogenic" (death by policy) could be appropriate, applied also to the 18,000 extra cancer deaths attributed to the conversion of NHS temples into Covid treatment centres.
Either way, the new rush of figures puts a different complexion on official claims – repeated by Johnson – that we are past the peak in this epidemic. Taking into account the care home and community figures, not only are they still going up, but they could be the highest in Europe (bearing in mind that other countries under-report deaths).
That rather makes a mockery of plans to relax the lockdown, as the very first test, requiring a "sustained and consistent" fall in the daily death rate does not seem to have been met. Only by relying exclusively on hospital deaths can that claim be made.
For all that, chief medical officer Whitty insists
that the trend overall is of a "gradual decline", even though he concedes that "we're definitely not consistently past the peak across the whole country at this point in time".
Given the official propensity for "bending" the figures, I am sure that that can be arranged in the near future. Such "adjustments" would suit the needs of our political masters, who are beginning to realise that the lockdown cannot be sustained forever. They have learnt well from their predecessors, absorbing the principle that, if you cannot control the problem, control the statistics.
When all else fails, though, they might consider addressing the basic principles of infection control and actually doing something constructive that will lead to an end of this epidemic. But, for the moment, that seems far too much to ask.