Predictions of the future are notoriously unreliable. Two contrasting opinions are seen here.
One is the simplistic view that the virus will evolve into a common cold virus, which is more of wishful thinking.
The other is that such a change will not occur.
Will explain below👇
One is the simplistic view that the virus will evolve into a common cold virus, which is more of wishful thinking.
The other is that such a change will not occur.
Will explain below👇
https://twitter.com/angie_rasmussen/status/1441416013883461640
Selection pressure is a term used in evolution.
It can be positive, which means those with advantageous mutations get selected over others, leading to an increase in its population. Example is delta variant in the case of SARS-CoV-2 virus.
Negative selection pressure is 👇
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It can be positive, which means those with advantageous mutations get selected over others, leading to an increase in its population. Example is delta variant in the case of SARS-CoV-2 virus.
Negative selection pressure is 👇
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Negative selection pressure also occurs in evolution, it is basically the force that gets rid of the “seconds” or “imperfect products” or those who have genetic changes that are deemed unfit for long term survival of the species.
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When this pressure is excessive, species become extinct.
If on the other hand this force (negative selection pressure) is too weak, that also is not good for the species; as “less fit” variants take over - and survival isn’t optimal.
In other words, both these forces exist.
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If on the other hand this force (negative selection pressure) is too weak, that also is not good for the species; as “less fit” variants take over - and survival isn’t optimal.
In other words, both these forces exist.
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The problem with predicting the future in the case of this virus are several.
1. Unlike most common cold viruses that might have taken hundreds or thousands of years to reach their present level, this one has had only 2 years experience with having man as a host.
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1. Unlike most common cold viruses that might have taken hundreds or thousands of years to reach their present level, this one has had only 2 years experience with having man as a host.
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2. This virus achieves its needs (i.e. to produce most copies & move to the next host) in the first 4 days of illness.
In other words, it doesn’t matter for this virus even if the person dies after that, as it has already moved on to other people (of whom there are plenty)
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In other words, it doesn’t matter for this virus even if the person dies after that, as it has already moved on to other people (of whom there are plenty)
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In other words, the death of the host doesn’t matter for the evolution of THIS virus.
(For other viruses that directly and invariably kill the host, that might be an issue, because they might literally run into a dead end)
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(For other viruses that directly and invariably kill the host, that might be an issue, because they might literally run into a dead end)
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3. The cause of death in the case of COVID-19 is not exactly the direct action of the virus, rather the anomalous immune response launched by a small subset of people, for reasons that aren’t known fully yet.
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That is, we still do not know why some people get just an asymptomatic infection, while others develop dreadful lung damage.
4. This virus also is hugely different from “common cold viruses”- it affects multiple systems in its hosts, including blood vessels & other organs.
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4. This virus also is hugely different from “common cold viruses”- it affects multiple systems in its hosts, including blood vessels & other organs.
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Hence, while it is comforting to engage in wishful thinking, & assume we know its trajectory, we must be mindful of the fact that many big predictions have so far been wrong about this virus.
What will make a massive difference however is an effective antiviral drug.
10/10
What will make a massive difference however is an effective antiviral drug.
10/10
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