No you mean originally?
Airborne_Again wrote:
Viruses tend to mutate so that they become more infectious and less dangerous
Fuji_Abound wrote:
I am slightly struggling with the logic of why the accepted trend is for a virus to mutate to become less virulent in terms of its mortality.
…. and others …
First of all, mutation is of course random, and the result can change both how easily the virus spreads (how much leaves the body and how, how long it survives outside, how likely it is to infect cells after entering the body etc.) and how bad the disease it it causes. And these factors are not all independent of each other, but this is well beyond my level of understanding.
The basic mechanism is
This favours three sorts of strains
Unfortunately that trend does not rule out that a new, faster spreading and more lethal variant appears; it is still the ‘luck of the mutation draw’
If we are unlucky, a more aggressive strain comes first, and it will get worse first.
As soon as a mild, rapidly replicating strain (which conveys immunity) emerges, the whole thing fizzles. Any more aggressive strains will be displaced, whether they came first or later.
The only question is what will happen first – aggressive strain, mild strain, widespread vaccination…
Cobalt – gosh I so hope I dont speak out of turn, but on a positive note I dont think there is any evidence or it is likely this group of viruses will cause a really high mortality, certainly I am nor aware of any evidence either in humans or animals, not that 1% is good, but in terms of some viruses I suppose there is some gratitude for the small mercies.
I would also have thought, perhaps more worringly, that every possible viable mutation will occur in a pandemic of this level. We can only imagine the billions of virus particles in circulation and the rapideness of the cycle of replication that just about every strain will be tested. Hopefully there will not be too many possible RNA combinations that result in a viable virus, and the population relatively quickly settles on the most successful – of course the same old mutations will keep popping up I guess all the time the virus is circulating. I think the biggest risk is if it “combines” with another RNA virus which I think is conceivably possible and then we could be in real problems because the vaccine is less likely to work. (Spanish Flu). Fortunately I think recombination is very rare for various reasons. This would therefore be really bad luck. The trouble is I suspect when a virus becomes so widespread it provides the opportunity for just about every permutation to be tested.
You are right with respect to your trio of virus types in terms of how they behave. The old childhood viruses are interesting. As you say they spread rapidly and some can cause severe illness. Outside childhood smallpox must be one of the most worrying examples given it had close on pandemic capability and was highly lethal. I think in the Americas it killed over 90% of the population. Never the less it clearly progressed in waves with significant outbreaks and then less active periods. Perhaps each wave selected those with some degree of immunity so over the ages each wave became more self limiting although still devistating.
but the good news is even smallpox mutated and there were less virulent strains. (Always end on a good note).
The chief of Biontech said today that he reckons the new variant will respond to his vaccine fine, but if it didn’t, they can knock up a new vaccine just for it in 6 weeks.
These two-dose vaccines must be logistically difficult because you have to aim the quantity you have been able to buy so it is delivered at the right rate so when you start dragging in the first-vaccinated group (mostly old peoples’ homes and NHS workers) for the second time, you have done the first group with half of what you have coming (well you get my drift).
The UK has now done 500k, and with no horror stories, it is obvious that the anti vaxx crowd has nothing to talk about, which is great.
I had measles at 12 and it was horrible, with permanent damage and problems. I absolutely cannot imagine any parent to wish the result on their child!
Are best estimates somewhere over 10% of the UK population has had COVID?
On the news now. High probability that you will get covid again with the “new” (UK) virus even if you already have had covid from the “old” virus.
Fuji_Abound wrote:
don’t think there is any evidence or it is likely this group of viruses will cause a really high mortality, certainly I am nor aware of any evidence either in humans or animals, not that 1% is good, but in terms of some viruses I suppose there is some gratitude for the small mercies.
Fortunately it does not look like it. I just wanted to emphasize the randomness of the whole ‘mutation’ thing…
Fuji_Abound wrote:
that every possible viable mutation will occur in a pandemic of this level.
Probably; but the sequence is crucial. Mild & fast replicating first – happy (well, happier) days.
Hence the the suggestion to create a mild strain deliberately is not that crazy, the problem is only how to create it safely and how to test it…
Peter wrote:
The chief of Biontech said today that he reckons the new variant will respond to his vaccine fine, but if it didn’t, they can knock up a new vaccine just for it in 6 weeks.
Well, they were able create the first one in around three months before starting Phase I trials in April, so this is plausible. It is a bit harder to see how they compress the testing timeline, though, it took seven months from start of Phase I to approval…
Frankly if it’s much the same vaccine with a very slightly different mRNA string to suit the new variant then any clinical trial is just going to be box-ticking.
In the circumstances, just roll it out and monitor it in general usage like you do anyway.
How long a vaccine trial takes to conduct is simply a function of how prevalent the disease is in the population. You jab your ITT population and wait for an analysis dataset to present itself. Unfortunately the better your vaccine the longer that takes.
Cobalt wrote:
Hence the the suggestion to create a mild strain deliberately is not that crazy, the problem is only how to create it safely and how to test it…
I think some of the research on the use of intraocular recombinant viruses is especially interesting and may be a more general pathway.
Despite the firebreak and lockdowns Wales seems to be leading the western world in new case rate
