Sunday 26 January 2020

How a virus like nCoV works?

First -Out of China

There are concerning (unconfirmed) reports in news channels and social media leaks that Novel CoV has infected now 90000.  This disease first emerged as a new viral pneumonia in seafood market workers in Wuhan China.
The virus is infectious during incubation, and Chinese authorities are now suggesting that where previously this incubation was thought to be  less than a week, it’s now reporting up to 14 days .

Let’s do a recap on how this virus works.

Transmission- droplet and contact, and faecal.

If someone with nCoV sneezes in a shopping centre, like measles, the virus is aerosolised and breathed in or, the virus settles on a surface (eg escalators hand rail, elevator button, coffee table).   Someone touches it, and then touches their own face or eyes, and has at that point become infected.
That is called transmission.

Now the virus starts to invade cells lining the respiratory tree, lungs, throat and nose. It enters the cell using enzymes to invite itself into the cell.
The cell tries to defend itself, by dissolving the virus outer membrane (the envelope) but this is what the virus wants; now the payload is exposed- the genetic instruction sheet called RNA.
Like a recipe book, the lung cell’s own genetic material (DNA) is altered by the virus RNA which now reprograms these cells to to start to make copies of the nCoV .

When millions of copies are made- the new viruses then burst out of the slave cell, killing it, and showering a spread of millions of virus particles to neighbouring cells.
The process repeats until so many cells have been damaged that the immune system responds.
This lag from Transmission to symptoms is called incubation time.
In Flu it’s 1-3 days, but this nCoV is now believed to be up to 14 days.  All that time, a person is shedding and spreading virus, and has no idea they were even infected or infectious.

Mutation:
The concerning issue at hand is that this virus is thought to have mutated in to a second generation- meaning it can be passed from human to human.  Previously it was thought to be purely zoonotic, transmitted by an animal to human only in its first generation.

As a virus mutates, it undergoes minor changes called Drift, but major changes like second mutations, are referred to as Shift.  This causes the host (is in this case) to not recognise the virus from one mutation to another.   Very difficult to pin down this virus yo produce a vaccine.

#ncov
Official death toll (reported) is currently at 80.
Cases in China, Japan, France, USA, Australia and no doubt third world nations with limited capacity to contain or report.
Written at 8am on 27th Jan 2020.