Lockdowns may prevent a natural weakening of this disease
Matt Ridley
Boris Johnson's fondness for the metaphor of the US cavalry riding to the rescue is risky: ask General Custer. With the vaccine cavalry in sight, and just when we thought we had earned a Christmas break, the virus has ambushed us with a strain that seems more contagious, and which is rapidly coming to dominate the epidemic in south-east England.
It is now a race between the virus and the vaccine as to which can get into your bloodstream first.
Lockdown sceptics are suspicious. Nervtag, the sinister-sounding "new and emerging respiratory virus threats advisory group", is dominated by people on public salaries holding the extreme view that all Covid risks must be considered and most economic, social, mental and physical effects of lockdown pretty well ignored, and they have clearly been itching to call off Christmas.
But that does not mean the new B117 strain is a myth or its danger is exaggerated. Britain does 50 times more genome sequencing of viruses than most other countries which means that we are cursed with knowing more about these mutations but not necessarily being able to do anything about them. Most mutations, thankfully, make little difference.
This one, however, is different because an unprecedented 14 sense-changing substitutions and three deletions in the virus's genomic recipe, rather than accumulating gradually, appeared all together for the first time in a patient in Kent on Sept 20.
The explosive growth of this strain, and the fact that eight of the mutations are in the spike gene (the key that opens the locks on a cell) implies that they make the virus more contagious.
This number of changes would normally take months to emerge at the rate the virus typically evolves: it is less prone to random mutation than an influenza virus. What caused such a burst of evolution within perhaps a single body?
Here the story gets alarming. According to analysis by Andrew Rambaut at Edinburgh University and colleagues for the Covid-19 Genomics Consortium UK, such high rates of mutation have happened in people with suppressed immune systems who get a Covid infection that persists for months and are treated with "convalescent plasma" - essentially blood extracted from those who have recovered from Covid.
In a person with a deficient immune system, a large population of viruses can proliferate, mutate and diversify, and then the treatment selects a new strain from among this diversity.
Essentially, the virus has a crash course in evolution. If so, this casts doubt on the wisdom of convalescent-plasma treatment, pitting the possibility that it might save a life against the possibility that it might help the virus become more infectious or lethal.
There is fortunately no evidence the B117 strain is more virulent, immune to one of the vaccines or can re-infect people who have recovered, though the last of these cannot be ruled out.
Viruses will always evolve to be more contagious if they can, but respiratory viruses also often evolve towards being less virulent. Each virus is striving to grab market share for its descendants. The best way of achieving this is to print as many copies of itself as possible while in a human body, yet not make that person so ill that they meet fewer people.
Where the sceptics have a point is that it is a worrying possibility that lockdowns could prevent this natural attenuation of the virus. They keep the virus spreading mainly in hospitals and care homes among the very ill, preventing the eclipse of lethal strains at the hands of milder ones.
If so, and it's only a possibility, then not only do lockdowns fail to wipe out the disease, they may be prolonging our agony.
We need that vaccine cavalry, and soon.
http://www.rationaloptimist.com/blog/lockdowns-may-prevent-a-natural-weakening/
*******************************What you need to know about the new variant of coronavirus in the UK
Many countries have closed their borders to people leaving the UK due to the rapid spread within the country of a new variant of the coronavirus that might be more transmissible. Meanwhile, South Africa is also reporting the spread of another new variant. Here’s what you need to know.
What do we know about the new UK variant so far?
B.1.1.7, as it is known, has 17 mutations compared with the original SARS-CoV-2 virus first discovered in Wuhan, China, including eight that may change the shape of the outer spike protein. Many of these mutations have been found before, but to have so many in a single virus is unusual. It was first sequenced in the UK on 20 September, but only caught the attention of scientists on 8 December, when they were looking for reasons for the rapid growth of cases in south-east England. On 14 December, the UK’s health minister, Matt Hancock, told parliament that a new variant that seems to spread faster had been identified.
How worried should we be?
There is no evidence so far that this new variant causes more severe disease or that it can evade the protection conferred by any of the vaccines. Some lines of evidence suggest that it spreads more readily, but the evidence isn’t conclusive. On 21 December, a UK expert committee on emerging viral threats said that they have “high confidence” that there is a substantial increase in transmissibility compared with other variants. “There is still more data that we need to get to be 100 per cent sure of this,” says committee member Peter Horby at the University of Oxford.
How much faster is it thought to spread?
The latest estimate is that it was 50 per cent more transmissible than other circulating strains during England’s latest lockdown, according to Neil Ferguson at Imperial College London, another committee member. However, it isn’t clear if this figure is true more generally, he says. B.1.1.7 is already responsible for 80 per cent of infections in London.
What does it mean if this variant is better at spreading?
“No matter how the virus changes, it needs us to be close enough to each other and to have interactions to let it jump between us,” says Emma Hodcroft at the University of Basel in Switzerland. “If we don’t give the virus those opportunities, it simply can’t spread no matter what variant it is.” In other words, standard control measures such as wearing masks and social distancing will still work. The new, tighter “tier 4” restrictions introduced in some parts of England, for example, will be effective if people follow the rules. But imposing such restrictions is obviously highly undesirable.
How did we discover these variants?
Standard tests look for the presence of the virus. It is also possible to sequence the entire genome of the virus, which is around 30,000 RNA letters long, to look for any changes compared with previously sequenced samples. Researchers around the world sometimes sequence samples to track the spread of the coronavirus and see if it is evolving.
What is different about the UK variant?
The mutations that might change the shape of the spike protein may allow the virus to bind to receptors on human cells more strongly and thus get into cells more easily. This may increase viral replication in the upper airways – initial results suggest there are more viruses present on average in swabs from people infected with B.1.1.7 than with other variants. There are also “hints” that it is more likely to infect children, says Ferguson.
And the South Africa variant?+
Around 90 per cent of infections in South Africa are now due to one variant, sequencing suggests, but much less is known about it. This variant, called 501.V2, also has 17 mutations, but only one is the same as in the UK variant. This particular mutation, called N501Y, has been around for a while – it was first seen in Brazil in April and has been detected in several countries since.
How unusual is it for the coronavirus to mutate?
Not unusual at all. In fact, there are tens of thousands of “mutants” that differ from each other by at least one mutation. But any two SARS-CoV-2 coronaviruses from anywhere in the world will usually differ by fewer than 30 mutations, and they are regarded as all belonging to the same strain. Researchers instead talk about different lineages.
Are the mutations in this variant helping it spread?
We don’t know. By chance, some coronavirus lineages do spread more than others. For instance, a variant first found in Spain spread rapidly across Europe in the summer. There was concern that this variant was both more transmissible and more dangerous, but this turned out not to be the case. Its rapid spread is now thought to be due to people travelling to Spain for holidays. However, Hodcroft, who studied the Spanish variant, thinks the UK variant really could be more transmissible. “There is an increasing amount of evidence that there might be a real difference here,” she says. “But nothing we have right now is conclusive.”
How do we find out for sure?
Health authorities will have to keep tracking variants to see if this variant spreads faster than others. Researchers also plan to carry out lab experiments to try to determine the effects of all the mutations. This will include testing antibodies from people who have been vaccinated or were previously infected to see if they are less effective against B.1.1.7.
Has the UK variant spread to other countries already?
Yes. So far, confirmed cases of B.1.1.7 have been reported only in Denmark and Australia, with possible cases in Belgium, Italy and the Netherlands. However, few countries do as much sequencing as the UK, so many cases could have been missed. Given that the UK variant was first detected in September, it is possible that it has already spread to many more countries – we should find out soon now health authorities around the world are looking for it.
So is it too late for travel bans to work?
They will still help, by preventing more introductions of the new variant and thus keeping down the number of cases and making them easier to control, says Hodcroft. “The goal here is more to buy time,” she says.
Can this variant be detected by normal tests?
The short answer is yes. However, some tests may need to be tweaked. The standard test for the coronavirus involves looking for any of three parts of the viral genome sequence. By chance, in some tests used by major labs in the UK, one of the parts is one of the mutated bits of the UK variant. This has turned out to be very useful. By looking at test results that came back positive for only two of the three parts – called S gene dropouts – health authorities have been able to get a much better idea of how fast the variant is spreading than would be possible from sequencing data alone.
Where did the UK variant come from?
“It very much looks like a point source in England,” says Susan Hopkins at Public Health England. In other words, it came from a single individual. There is speculation that it could have evolved in the body of a person with a weakened immune system, meaning the immune response wasn’t strong enough to kill off the virus but did force it to evolve. This would help explain why it has more mutations than normal.
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"Mr. Hawley’s challenge is not unprecedented... Democrats in both the House and Senate challenged certification of the 2004 election results..."
"... and House Democrats tried on their own to challenge the 2016 and 2000 outcomes, though without Senate support. ... Senator Barbara Boxer of California... briefly delayed the certification of George W. Bush’s victory... cit[ing] claims that Ohio election officials had improperly purged voter rolls... which Mr. Bush carried by fewer than 120,000 votes. Nancy Pelosi, then the House Democratic leader, supported the challenge.... The House voted 267 to 31 against the challenge and the Senate rejected it 74 to 1...
After the 2016 election, several House Democrats tried again, rising during the joint session to register challenges against Mr. Trump’s victory over Hillary Clinton in various states. The Democrats cited reasons ranging from long lines at polling sites to the Kremlin’s election influence operation."
From "Hawley Answers Trump’s Call for Election Challenge/The Republican senator said he would object to certifying the Electoral College votes on Jan. 6, a move that is unlikely to alter President-elect Joseph R. Biden Jr.’s victory" (NYT).
So... in the last three decades, every time a Republican won, Congressional Democrats challenged the certification of the election, and every time a Democrat won, Congressional Republicans did not challenge the certification.
That certainly puts a different light on what Josh Hawley is doing!
Either challenging the certification is the norm or it is not. It can't be the norm for Democrats and abnormal when a Republican does the same thing. Either Congress has a role in looking into the workings of the state elections or it does not. It can't be that the role is to question Republican victories and rubber-stamp Democratic victories.
https://althouse.blogspot.com/2020/12/mr-hawleys-challenge-is-not.html
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