A Strathspey and Badenoch update on Covid-19
As it all began two months ago, retired virologist Anne Bridgen, of Newtonmore, kindly gave Strathy readers some idea of how things might pan out. With things changing all the time, we consulted her again this week.
Observing the required social distancing, she and her partner Ian Bradbury, a former statistician at Kincraig’s renowned Frontier Science conferenced with Catherine Cargill – a GP who retired to Strathspey some three years ago – to produce a very timely Question and Answer briefing on Covid-19:
"It has been devastating to watch this tragedy unfolding. Our news channels are full of updates on the disease COVID-19 and SARS-CoV-2, the virus which causes it. Nearly all of us are experiencing fear for ourselves and our loved ones as well as severe economic loss. However, there seems to be very little coverage of what is actually happening, so here is a quick update.
Why is it called a coronavirus ?
When virus particles are negative stained and viewed using electron microscopes a crown, or corona, can be seen on the outside of the virus. This is caused by the globular spikes of the virus entry (spike protein) projecting out of the virus membrane. These spike proteins are really important, as they determine which specific cells the virus infects, and thus what disease the virus causes. In addition, as they are on the external surface of the virus, they are the main protein that induces anti-viral antibodies.
What are we learning of the virus?
The first SARS-CoV-2 virus sequence was published on January 11. Since then, thousands of virus sequences have been generated. This is in itself a great achievement – a few years ago it would have taken several years to generate the first sequence using available technology. The sequences can be compared against SARS-CoV-1 from the 2002 outbreak, which shows that the viruses are closely related, but there are still marked differences. Obtaining the sequence is the essential first step to allow diagnostic tests for the virus to be developed and also a starting point for vaccine design.The sequences can also be compared against each other to see how the virus is changing. Overall the virus sequence seems to be pretty stable, which might be expected from a virus which is spreading so successfully. There are some mutations, which roughly mirror the geographical spread of the virus, but most changes appear to be minor, either base changes or small deletions. This is important, as mutations could alter the nature of the disease, and will certainly affect whether vaccines continue to work and whether you can be reinfected with the virus.
Where are we with vaccine design?
A recent Nature journal article describes 78 current vaccine design projects, of which five are in stage 1 clinical trials (human safety testing). This is staggeringly quick progress, but use has been made of the SARS-CoV-1 research and also these five are largely relatively simple approaches using the virus spike protein described above. More complex approaches using modified live virus are likely to both take longer and be more likely to generate longer lasting immunity.
What kills the virus?
The virus has a fatty coat covering derived from the host cells. It is delicate, so solutions of 70% alcohol, dettol sprays or similar will kill it, as will hand-washing in soap and water. Once they dry out, the shape distorts so they are no longer infectious, so survival on dry surfaces like envelopes is quite short (under 24 hours) but it is longer – up to five days – on plastic surfaces. Leaving your post and non-perishable grocery deliveries for 24 hours before opening/bringing in is thus a sensible precaution.
How can science help with ending lockdown?
This is another question we all want an answer to! We can only safely move out of lockdown when we know there is no virus circulating, and/or we can track contacts of infected folk using phone apps. The problem is, none of the tests is perfect.
Dr Cargill advises:
1. The virus infects you by getting into your mouth, nose or eyes usually from droplets created when someone infected is nearby. A sneeze or cough will send virus-laden droplets several feet away, but even breathing and talking can cause spread.
So washing your hands frequently and always before eating or touching your face, is essential. Some people have started wearing surgical-type gloves, but the trouble with this is that unless you’re a health care worker and in the habit of treating your gloved hands as ‘dirty’ then the gloves can transmit infection just as your bare hands would, and perhaps give you a false sense of security – so hand-washing is better.
Friends of mine have seen people in the supermarket, for example, wearing a mask and gloves and pushing their trolley around, squeezing fruit to check its ripeness with their gloved hands, and absent-mindedly pushing their mask up to scratch their nose, still with the same gloves on.
All a bit pointless! Cloth masks can be useful, certainly to stop you passing a possible infection on to others, but bear in mind that they get damp quickly, and potentially laden with your own viruses, so do be careful taking them off; also viruses are small so can pass through the gaps. The NHS COVID-19 advice isn’t currently recommending everyone wears these, but this may change.
2. It is becoming clearer that there are many people who get the virus but don’t feel unwell, or have different symptoms from the classic ‘cough and high temperature’.
3. Many viruses, including the one causing COVID-19, tend to cause a more severe illness in someone with a bigger ‘viral load’. This means that you’ll tend to be more unwell if you’ve been in repeated close contact with a carrier, or if you’ve been in a gathering of people some of whom will be infected and who won’t necessarily know they are; hence the ‘social distancing’ rules, and also the instructions to stay at home except for exercise. Travelling around the country will help to spread the virus around and is hence not advised. We are still some days away from the ‘peak’ of
the pandemic in the UK – and up here in the Highlands it’s likely that we’ll be behind more central areas or bigger towns – but we still need to behave as though everyone we might see while shopping or exercising is a potential source of infection.
4. Do feel free to ask advice about COVID-19 and other illnesses. It seems though some people, and parents of children, are delaying asking for help or advice about other possible serious illness. Please don’t do that! If you’re unwell, ask for advice and help.
5. Try to get some exercise every day, especially if you have been advised to stay at home for 12 weeks. It’s good for us generally and, if we can go outside, will also get us some sunlight exposure to keep up our vitamin D levels. If you can’t get out, consider asking your pharmacist about taking a vitamin D supplement.
6. As always, incorrect advice and half-baked pseudo-scientific theories abound. If something sounds odd, far-fetched or too good to be true, it’s probably nonsense. You’ll do best to stick with the NHS information sources.
