Coronavirus: risk factors

07/05/2020

It is not so much that I instinctively distrust official information on hospital infection. I have had an interest in this subject ever since March 1977 when I was an environmental health officer in Leeds, suspended from my post after leaking a "secret" report revealing the parlous state of hygiene in NHS hospital kitchens.

Subsequently, after leaving local authority service, I led a World in Action documentary, aired in 1986, in which I made a number of covert inspections of NHS hospitals. They showed the world exactly what we were dealing with. This action, I like to think, was instrumental in securing the removal of Crown Immunity from hospitals.

But it didn't stop there. I was also commissioned to do some work on hospital infection, whence we started looking at concealed outbreaks with some very serious implications. However, the subject was too hot even for World in Action and the project was abandoned.

Occasional professional activities have led me to believe the situation hasn't changed very much, and we still see reports of major outbreaks of hospital infection, where specific hospital authorities have been dragged kicking and screaming (in a manner of speaking) into admitting they have a problem.

Early on in this Covid-19 pandemic, it was quite obvious that hospital-acquired (nosocomial) infection was going to be a problem, not least from one of the risk assessments produced by the European Centre for Disease Prevention on 8 April, stating that:

Up to nine percent of all cases in Italy, 20 percent in Lombardy and 26 percent in Spain were among healthcare workers. It is probable that nosocomial outbreaks are important amplifiers of the local outbreaks, and they disproportionately affect the elderly and vulnerable populations. Infection prevention and control (IPC) practices are of critical importance in protecting the function of healthcare services and mitigating the impact on vulnerable populations.

Interestingly, only a few days later , on 14 April, the Glasgow Evening Times ran an article headed: "Pressure on government to reveal information about hospital-acquired coronavirus at Queen Elizabeth University Hospital".

The article itself told us that "patients in more than half of Scotland’s health boards are thought to have contracted coronavirus while being treated in hospital for other conditions", with the Scottish Government being urged to tell the public exactly how many people had been infected.

This was at a time when nine of the country's 14 health boards had recorded potential cases of hospital-acquired Covid-19 in their facilities, including nine patients at the flagship Queen Elizabeth University Hospital. They had picked up the virus while staying there for more than 14 days.

Needless to say – and entirely in keeping with the official treatment of hospital infection episodes – the Scottish Government refused to give any details on the number of patients affected.

The famous Nicola Sturgeon said the issue of hospital-acquired, or nosocomial, infections was "one of acute study and explanation… to make sure everything possible if being done in hospitals to restrict, reduce and contain that", declaring that the figures would be published but currently the information was "not robust and reliable" enough to do so.

Surprisingly enough, the information has still not been released. Presumably, it is still not "not robust and reliable" enough. What we have seen, though, is a reassuring study in the Lancet carried out in Newcastle upon Tyne which, rather conveniently suggested that "nosocomial transmission from patients to staff was not an important factor".

Somehow, this obscure paper, from the backwater in the fight against Covid-19 - where incidence is low and there are few deaths - was thought to be important enough for the BBC to report it, with the headline: "Test data 'reassuring for front-line healthcare workers'".

The cynic in me finds this just far too convenient and, while this dealt with patient-to-staff infection, so far, I have not seen any comparable paper on staff-to-patient infection – even though a Chinese paper reported that, among the confirmed patients admitted to hospitals, the proportions of nosocomial infections were 44 percent.

If one carried over this figure into the UK, and applied it to the death rate, this could be taken to suggest that something over 10,000 of the deaths from Covid-19 reported in UK hospitals related to patients who had acquired their infection in hospitals. That would make the NHS the largest single cause of death in this national epidemic.

Of course, we don't have enough data to make that supposition but then I would be pretty confident that we'll never have those data. The one thing at which the NHS excels is in keeping secret its overall infection rates – and you can bank on Covid-19 being no different from the rest of the diseases caused by hospitals.

Of immediate practical importance though, is the perception of this epidemic and its profile. If, as we reported yesterday, infection in the community declines, hospitals and other healthcare locations (such as care homes) can become correspondingly more important in the perpetuation of the epidemic.

In this secretive system, though, "robust and reliable" information is the very last thing we are going to be given, especially where the sacred NHS is the object of official deification. There is no way this government can turn round and admit that its temples of healing are a major part of the problem.

Interestingly, the BBC ran a feature yesterday reporting that some older people who become acutely ill and need hospital care are now getting it at home.

New services, the report told us, are being rolled out at speed in some parts of the UK, aimed at preventing those who are frail and vulnerable from having to go into hospital where there's a risk of catching COVID-19. But all we are allowed to know is that: "Doctors say they knew they had to act fast to protect patients here when they saw the tragic deaths of so many older people in hospitals abroad".

Nothing, of course, is allowed to disturb our view of the sainted NHS, with the view that the National Covid Service is now so dangerous for ordinary patients that it is unsafe for them to be treated in their facilities.

Even if the "hospital at home" scheme is an admirable response to the problem, the lack of candour is troubling. By obscuring the role of hospitals in the perpetuation of infection, we create a distorted picture of the current epidemic dynamics. This might have important implications for how the lockdown is lifted, and on the emphasis given to control measures.

It may also be hindering our better understanding of the infection dynamics, as the issue of infective dose starts to penetrate the popular media – even if they can't get the terminology right, talking about "viral load", which is something completely different.

Nevertheless, the Mail retails the views of University of Bristol's Professor Lucy Yardley. Dripping with prestige, she is apparently warning that "the amount of coronavirus you get infected with decides how severe the illness is".

This, she says, explains why so many healthcare workers - who come into face-to-face contact with gravely ill patients - have fallen victim and died from the disease. She thus thinks that this should be factored into ministers' lockdown exit strategy.

Yardley also warns that the virus could be deadlier if it spreads within families in the same house because of the prolonged close contact, thus hinting at the multiple exposure phenomenon, without actually spelling it out.

After I wrote my piece on this, I received several private messages telling me of how single members of families had become ill with fairly mild symptoms, but the family members who had done the nursing had also fallen ill, in each case with more severe symptoms.

There may have been confounding factors, but the experience is consistent with multiple exposure infection. And if this is a significant issue, it does change the way we need to look at social distancing and contract tracing.

Most likely, casual, single contacts are unimportant, and the emphasis should be on avoiding situations where people are exposed to continual or multiple infections over a period of time. And, as we also see that hospital areas become highly contaminated, we may need to look at treating Covid-19 sufferers away from traditional hospitals.

In terms of exposure, though, as well as healthcare and home nursing situations, we might think about checkout operators in supermarkets, bus drivers and any occupation with frequent customer interface – all of which might be regarded a "high risk". On the other hand, contacts in the street, parks and in other open spaces, may be irrelevant.

If we are to make any serious progress in controlling this disease, therefore, we need a lot more information than we have at the moment, and one place to start looking is in NHS hospitals.

Certainly, any relaxation in the lockdown should be guided by a better appreciation of risk factors, and that means understanding how, and in what circumstances, the most serious infections occur.