It is June and the UK has had over a quarter of a million confirmed cases and 40,000 deaths from covid since the start of the pandemic.
This is double the early worst-case predictions, is the largest total number of deaths and the highest rate per 1m population in Europe.
Thankfully, during the peak in early April, when the death toll topped 1,000 per day, the NHS made space for, and managed to treat, everyone who presented.
The combination of lockdown and public health measures have slowed the daily rate of serious cases and deaths considerably and while we still have a higher daily death and infection rate than other countries we are currently in a lull and there is a gradual resumption of services.
Yet we are still seeing around 8,000-9,000 symptomatic cases of covid and 200 to 300 deaths per day, so the virus is still significantly affecting many Britons.
In addition, the virus itself has proved to be a more cunning enemy than anticipated and the longer-term consequences of infection are only now starting to be understood.
However, we are a long way from being through this pandemic and there are some important considerations to reflect upon. We need to understand where we are, what we know, what we don’t know and what we can do from this moment on and I hope to be able to set that out below.
The virus enters through one of the mucus membranes in the face: the nostrils, the mouth or the conjunctiva of the eyes, transmitted directly by breathed out air containing viral laden particles or via indirect transmission eg hand or object.
Through those mucus membranes it gains entry to the body, where it finds cells with a specific receptor on their surface which allows it to pass into the cells and use the cellular machinery to replicate itself.
The multiplied virus then kills the cell which spews out the virus to find other cells within the same body or be expelled to find another body to replicate within.
Unfortunately, the receptor used by the virus to gain entry into cells is fairly ubiquitous in the body, being found in lungs, kidney, blood vessels, gut, testes, brain and heart amongst other places. This is one reason the symptom repertoire of this virus is extremely broad.
Early in the infection, the body’s natural immunity is triggered in order to tackle the virus immediately.
The smaller the viral inoculum (amount of initial infection) the better chance the immune system has of preventing too much damage being done. In some people the virus is cleared by the immune system without producing any symptoms or after a long incubation period and a pre-symptomatic phase.
The likelihood of the virus being cleared with no, or mild, symptoms only, therefore depends in part on the mildness of the infection, the strength of the individuals immune system and the absence of additional risk factors.
· Being male
· Pre-existing conditions especially if poorly controlled, eg hypertension, diabetes, high cholesterol, cardiovascular disease, respiratory disease.
· Ethnicity eg Black, Asian, especially if low vitamin D levels
· Blood group A
Immune-mediated progression of covid
Initially, it was thought that severe complications from covid were related to acute respiratory distress. This is a syndrome where the lung infection is overwhelming, lung tissues are damaged, significant mucus and fluid collects, all of which prevents the oxygen reaching the blood.
Treatment for this condition is ventilation where oxygen is pushed into the lungs, displacing the fluid so the blood can become oxygenated once more.
Unfortunately, this virus does something different. If allowed, it will over-stimulate the immune system into triggering the blood to clot more easily. This results in blockages in the tiny blood vessels which surround the air sacs.
This means that the drop in oxygen levels seen in severe disease is not so much due to the oxygen not reaching the blood, but more to do with the blood not flowing around the air sacs to collect it. The treatment is therefore different and ventilation should be a last resort.
This clotting response can also happen elsewhere in the body, both in capillaries affecting other organs and in larger vessels eg causing pulmonary emboli and DVTs all of which impede recovery and may cause longer term damage.
Covid infection therefore seems to be a disease of at least two parts, the initial viral replication phase and the immune mediated tissue-damage phase. As such, treatment options may vary according to which phase of the illness you are in.
Anti-viral treatments should be used early, and clotting plus immune modulating treatments if complications arise. Treatments are currently being trialled the world over and more evidence is being produced daily regarding their efficacy.
Children and covid
Initially, we were fairly confident that children were less susceptible to covid and that is still true. Many studies show that fewer child
ren are infected and to a lesser extent, with only asymptomatic or mild illness. Studies looking at transmission, seem to suggest that children are not the main vectors, although that might relate to behaviours in lockdown, where children are unlikely to go out and become infected then bring it back into the home.
However, in flu, it is clear that children are significant spreaders and there is a lack of obvious signs suggesting that is true in covid. I would expect this to be clearer if it were true, especially as children are not very good at following public health advice. Overall, it seems that the risk to, and around, children is lower than for adults, but not zero; one consideration to bear in mind however, is that even if they are less likely to transmit the virus, they are more likely to do so silently.
However, what has emerged is that, rarely, children and young people up to 21 years old can develop a late complication of the virus infection; a post viral vasculitis, similar to Kawasaki Disease. It is likely that this is triggered by an auto-immune response, causing a breakdown of the tissues, specifically blood vessels, rather than a direct viral effect. The good news is that this is very rare. It should be easy to spot because the child will be obviously unwell with some key features:
If caught early, this condition can be treatable, so seek medical advice immediately if you have any concerns. The child may not show any signs of a covid infection, but if they have, this syndrome may emerge 3-4 weeks after infection.
One of the concerns about the pandemic is that people are coming late to GPs or A&E. Speak to a GP/A&E if there are any concerns regarding this in order to have your child assessed, but be reassured knowing that this syndrome is very rare.
One of the worrying features about this disease is the emerging evidence that recovery can be prolonged or that there may be long term consequences. Some people have found a very slow return to normal with persistent breathlessness, chest pain, unrelenting fatigue or aching.
We don’t know enough about this yet, but we will get more evidence as time goes on.
There is also evidence of long term damage to organs especially lungs and kidneys in patients who had severe disease. Avoiding it or getting a mild dose should be a priority for those who have not had it.
Progression through the pandemic
Despite the numbers involved, we are at the early phase of this pandemic. All the work we have done as a country has flattened the curve so that all those who have sought treatment have been able to receive it and transmission has slowed. Fewer people are becoming infected each day. Official numbers show that 3.8% of the population has been confirmed as having been infected, but modellers have calculated that between 10-20% of the country has been infected.
We are hopeful therefore that 10-20% of the country are now immune to reinfection, at least in the short term, however, it also means that 80-90% of the country are still susceptible. We
therefore need to find ways of living with this virus in ways that allow our society to reopen
without putting the most vulnerable at risk.
Two principles are helpful when considering what we need to do. Firstly, and most importantly, we must minimise the risk of being infected in the first place. Secondly, given that it’s impossible to avoid completely, we need to ensure that if we do get infected, the amount of virus we have encountered is small.
This means that we are likely to get a milder disease. By doing this, we will slowly increase the numbers of immune people at the lowest cost to ourselves and society. Non pharmacological interventions are at the heart of both of these principles.
Non pharmacological interventions
Most transmission seems to occur indoors in shared spaces especially if ventilation is poor.
The virus is emitted from breath, most densely in droplets, and lingers in the air for up to three hours and on surfaces for several days. The following measures reduce transmission and contribute to a reduced inoculum for oneself.
Wear a mask or face covering protects individuals and society not by acting as a filter to
prevent single viruses passing through, but as a barrier to the emission of viral laden droplets
landing on someone's face or into the atmosphere to hang in the air as well as offering
protection against the inhalation of droplets emitted by others.
Use a clean one each day and have about 2-3 to use in rotation. This would increase your chances of having mild illness if you were to catch it despite all your measures. The virus only lasts about 24-48hrs on absorbant surfaces. Touching a mask is like touching your face, so #WashYourHands. Adjust by straps.
Using them "incorrectly" is NOT high risk, it's just less effective. Any barrier for any amount of time contributes. Still keep #2mdistance wherever possible.
Additional sensible measures include not sharing objects, especially ones you touch frequently or might put in your mouth (eg pens), ensuring rooms have good ventilation or convene in outdoor spaces. Stay at home where possible. Some potentially highly social activities, such as singing, seem to be exceptional at causing widespread transmission.
Ensuring a robust immune system
A further component of achieving mild or asymptomatic disease is to ensure resilient immunity.
Firstly, prioritise good mental health. Good mental health will not only optimise your
physiology, but it also makes it easier to do all the other things that are needed, especially if
they are new or challenging. Good mental health depends on good sleep hygiene, connecting with loved ones, being mindful and responding appropriately to emotions, allowing yourself or others to look after yourself.
Secondly, if you have any underlying health conditions, ensure they are as well controlled as
they can be. Make sure your blood pressure is at the right level, if you are diabetic, control your sugars, if your cholesterol is high, ensure it is treated appropriately etc. Eat nutritiously,
exercise regularly and maintain a healthy weight.
Evidence is emerging of links between covid and specific vitamin deficiencies so ensure you are getting your recommended daily amount, either through diet or supplementation. Adequate Vitamin D level reduces the likelihood of catching and the severity of a respiratory infection with some evidence specifically linked to covid.
Most vitamin D comes from the sun, so levels can be low in the UK, especially if your skin is dark, as melanin blocks Vitamin D manufacture, so consider 25-50mcg supplement daily. Low selenium has been associated with worse outcomes in severe covid infections, brazil nuts and eggs are a good source, among other things.
Zinc is implicated in the mechanism of entry of the virus and low levels may make the virus more virulent. Zinc cannot be stored easily by the body. There is no direct evidence, but personally I would recommend ensuring you are taking adequate amounts.
Unless you are eating 3 oysters daily, which is a challenge for anyone, consider a supplement. It is better to have supplements of specific minerals rather than multivitamins as they tend to have not quite enough of anything.
This virus causes more complex problems than we have seen in other respiratory diseases. We cannot wholly rely on getting it, recovering and moving on either individually or as a society.
It can affect us badly or even cause serious long-term consequences, but it looks like it is also here to stay, so we need to find ways of living with it as well as we can without compromising the most vulnerable in the community.
Whilst the medical profession and researchers are finding treatments and vaccines, and the public health officials are tracking, tracing and isolating clusters, we as individuals need to ensure that we play our part in making sure that we break chains of transmission, if infected the viral load is minimal and make certain that our immune systems are in tip top condition to nip it in the bud.
This needs to become our normal way of thinking, but balanced, so we can manage this for the long term.
It is worth bearing in mind, that these practices will also reduce the transmission and severity of other respiratory illnesses such as the cold, flu and chest infections, which will help over the winter months when those illnesses also start to rise.