Living with Covid19

16 July 2021

On July 19 in England all legally mandated Covid 19-specific restrictions are to be lifted. In Northern Ireland, Scotland, and Wales the pace of easement is slower, though around mid-August legal restrictions will be similarly eased. The removal of legal restrictions will still leave in place government guidance on the wearing of face masks and social distancing in crowded indoor spaces. However, the relaxation of laws and social rules is being done at a point of time when, in a number of local areas and regions in the UK, there are rising cases of confirmed cases of Covid (principally the now dominant so-called Delta variant).

Public opinion in the UK is divided on the wisdom of the ending of legal restrictions and reliance substantially on individuals’ exercise of caution. Opinion polls seem to suggest that around two-thirds of the population will remain cautious.  If, as is hoped, the current exponential increase in cases detected (doubling roughly every 9 days) starts slowing in 2/3 weeks then the public caution will likely reduce. Hospital admissions on the other hand appear to be doubling every 20 days. The median length of stay appears to be between 5 and 7 days.

In essence, what is being undertaken is a move towards the UK population learning to live with the virus, as one that will be endemic. The main reason why this is being instituted is because of the high and increasing overall levels of vaccination, especially in the identified vulnerable groups (broadly the over-70s and those with comorbidities, such as diabetes, frequently linked with obesity.

Supplementing the high vaccination rate, currently around 65% of the adult population has been double-vaccinated are those not often included, mostly below 30 years who have already experienced a Covid infection and will have substantial natural immunity. This accounts for between 15% and 20% of the adult population. Taking these two percentages together suggests that there is between 75% and 80% herd immunity. The ONS recently reported that 80% of the UK population has antibodies against Covid, which confirms this estimate.

One of the problems throughout the pandemic has been the failure of  politicians and some scientists not to provide adequate information to the general public. It is not clear whether some of the epidemiologists understand the considerable caveats surrounding their modelling. As with all models, including the economic models which I am most familiar with, they are substantially inaccurate pictures of potential reality.

The assumptions of the epidemiological models are often imprecise matches to the structures of the real world, such as how people interact with each other in social settings; there are significant uncertainties about how certain variables will behave, for instance the virus; the models, post vaccination, are extremely e sensitive to small changes in the assumption of vaccine efficacies, etc. The outputs of the models should be regarded as maps drawn by partly blindfolded cartographers. They may point you in the right direction, but many topographical features will be missing.

One problem rarely indicated is that there is no test for infectivity, only for the amount of viral load, that may or may not be infective for a person in contact with you. Essentially, the PCR test indicates a relatively arbitrary amount of virus present in the nose and throat. In a given individual this amount may or may not prove either not to be infective at all, or, more likely of varying severity. The problem with this virus is that its effect on individuals depends critically on both the viral load and their immune system response. This problem is confounded because the virus invades blood cells, not only, and predominantly, in the lungs, but also in other key organs of the body.

Usually, immune response measurement is restricted to reporting antibody levels. For instance, the ONS figure of 80% of the UK population having antibodies, reported above, ignores the important impact of the immune system B-cells ad T-Cells that destroy infected cells.  This is why if individuals, usually young and the non-double vaccinated, contract a second infection, in almost all cases it will be mild. There will, of course, always be exceptions, because of the unpredictability of individual immune systems. But these will be rare. It is also the cases that vaccination, for a number of people for whom vaccination, as with any significant medical treatment, will have a risk. Current figures suggest a 1 in 24,000 risk of  death. This compares with 1 in 16,000 for each car journey taken in the UK. For people below the age of 40 the JCVI do not recommend taking the Astro-Zeneca vaccine, because of the balance of risk between the harm of Covid and the harm caused by vaccination.

Notwithstanding the view that Covid should be considered a serious disease, with lasting impacts from the severe form of the disease. there has been an attempt to paint it as perhaps more severe than it deserves for the average person contacting the disease, and to induce a climate of fear concerning the disease. In 2020, and especially in Spring of 2020, this stress on the danger of contracting Covid was to cover the lack of preparedness for the pandemic and, critically the lack of NHS capacity. The fear was used to justify the severity of the initial, albeit late, lockdown  in March 2020, aimed at reducing substantially social contact, and hence contagion, especially for the vulnerable.

Disgracefully, the problem of being unprepared for the pandemic, was exacerbated by the government proceeding, still without a plan, to make a catalogue of errors during 2020 and 2021. This trajectory, resulted in another lockdown from late December through to March, again straining an under-resourced NHS, including public health and general practice. The 2021 lockdown, was partly related to the emergence of a more contagious virus variant, identified in Kent. This action, especially in the winter (and potential for a surge in flu cases) may have been necessary. However, ironically, in the current situation, though the Delta variant cases are rapidly increasing in some areas, all legal restrictions are being removed from July 19 in England. It is of course likely, as indicated above, that we are approaching herd immunity, via the vaccination programme and natural immunity, so there is less cause for concern. The rise of cases may soon slow down, in terms of its rate of doubling in the affected areas, and probably peak sometime in August. However, the public having been scared over the past 15 months should have been given a more phased ending of restrictions, not an arbitrary cut-off date.

A further problem of the government’s making that is now surfacing is the test and trace app that is now pinging toadvising people to self-isolate, and is creating problems for businesses and the NHS, even with those who have been double-vaccinated. The validity of the app is by no means guaranteed to be accurate. Many individuals are likely to delete the app or ignore the advice.

Most of the Covid cases (of the now dominant Delta variant of the virus) appear to be mostly young people having a mild infection, with relatively few severe cases occurring Hence, the rise in cases, though rapid in certain areas, such as  North-East England, is not yet a cause for major concern. The summer weather will mean that more people will be outdoors where the chances of infection are far lower. I have never understood why people wear masks outside, especially where long, close interactions with others are limited.

Finally, it needs to be said that the pandemic has been a salutary reminder of human interaction with nature. Humans exist side by side with viruses. These strings of proteins need animals, including humans, to survive. This latest, contagious, virus to emerge, Covid 19, has reminded a us of this fact. As with other viruses we will learn to live with it, perhaps, like flu (notwithstanding certain differences between the two diseases), the vulnerable needing to be protected by regular, though probably less frequently than flu, vaccinations. Supported also by an inevitable, widespread acquisition of natural immunity.

Michael Lloyd

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