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Covid-19: what you need to know today


The big news on Monday was the big news on Sunday, which was the big news on Saturday – the new strain of coronavirus in the UK. Following the lead of many other countries, India also stopped flights from the UK until the end of the year, but it may be too late. According to a report on virological.org by researchers from various UK universities, the report was written for the Covid-19 Genomics Consortium, UK, a public-private partnership that seeks to “collect, sequence and analyze the entire genomes of samples UK virus ”: the first samples of the strain (now called B.1.1.7) were collected on 20 September. That’s three months ago, which probably means that most countries ban travelers from the UK or stop flights to and from that country, it’s probably too late. There is a very high probability that the strain has already entered your countries.

Between the time I wrote Dispatch 229 on Sunday and the time I write this, scientists have discovered even more about this strain, and the bad news appears to be that, at least in a laboratory setting, it is more infectious than older strain. It also turns out that the strain is now the dominant one, at least in the UK, but that should come as no surprise: this is how mutations usually work. According to the virological.org report, three of the multiple mutations in the new strain (17, by most reports) are interesting. One, which I wrote about in yesterday’s dispatch, the N501Y Mutation, causes a change in the virus’s spike protein, possibly causing it to bind better to human cells; another, also in the spike protein, could, the researchers suspect, help the virus evade the host’s immune system; and the third, whose effects are unknown, is near the spike protein cleavage site. This is the site that reacts with the human enzyme furin, resulting in the breakdown of the peak protein in two parts, with one part (S1), adhering to the ACE receptor found in human cells, facilitating the entry of viral matter. . It’s easy to see how all of this could make the new strain more infectious, but as I pointed out yesterday, we won’t know for sure until more infectivity studies are done and more virus genomes are analyzed, and both must happen the world.

India may be experiencing a hiatus in new cases, but this does not guarantee that the new strain is not already here. The country has had a so-called travel bubble with the UK since May, with 70 weekly flights between the countries. This can be established by large-scale genomic analysis. India has been analyzing viral genomes from across the country, and while this does not appear to have been on the same scale as the UK, if there was a new strain of the virus rapidly emerging as the predominant one, it would likely have been picked up.

The UK scare is likely to push India (and many other countries) to sequence more virus genomes. According to an article in Science (sciencemag.org), UK efforts to identify the new strain were aided by the fact that one of the commonly used RT-PCR tests in that country, TaqPath, showed fragments of just two genes in the result. whether the virus was the new strain (compared to fragments of three genes from the older strain; one of the genes is hidden by one of the mutations). This kit is also approved for use in India (according to the Indian Council of Medical Research website), but this columnist doesn’t know how many, if any, labs use it. That would be a good starting point for research from India on the new strain.

Original source