Re: B.1.1.529 Omicron variant
Posted: Sun Dec 19, 2021 8:36 pm
THERE'S NO SUCH THING AS DECOUPLING YOU JUST AREN'T THROUGH THE LAG YET
Eldest, who's a pretty social late 20s Londoner, has cancelled all outings to protect his family Christmas. Says lots friends have tested positive, particularly those who've been going out.gosling wrote: ↑Sat Dec 18, 2021 5:45 pmWe met a friend for lunch yesterday in Southwark. Considering it was the last Friday before Christmas Eve we assumed the restaurant would be busy and had thought about cancelling. Turned out we were the only ones there apart from the staff. The tube was still pretty busy though. So a semi-strong voluntary lockdown in London.
We are observing doubling time central estimates of less than 2 days for every region except the South West. This may be related to poor PCR gene target reporting coverage in this region.
A growing body of preliminary research suggests the Covid-19 vaccines used in most of the world offer almost no defence against infection by the highly contagious Omicron variant.
All vaccines still seem to provide a significant degree of protection against serious illness from Omicron, which is the most crucial goal. But only the Pfizer and Moderna shots, when reinforced by a booster, appear to have initial success at stopping infections, and these vaccines are unavailable to most of the world.
Well the anecdotes from the lab covid club are that basically those who had two AstraZenecas but no booster caught it, and the boosted ones didn't. And this might still have been Delta.jaap wrote: ↑Mon Dec 20, 2021 9:58 amhttps://www.deccanherald.com/internatio ... 62625.html
A growing body of preliminary research suggests the Covid-19 vaccines used in most of the world offer almost no defence against infection by the highly contagious Omicron variant.
All vaccines still seem to provide a significant degree of protection against serious illness from Omicron, which is the most crucial goal. But only the Pfizer and Moderna shots, when reinforced by a booster, appear to have initial success at stopping infections, and these vaccines are unavailable to most of the world.
Yes, I've seen some pretty poor results for AZ, Janssen, Sinopharm and Sputnik.jaap wrote: ↑Mon Dec 20, 2021 9:58 amhttps://www.deccanherald.com/internatio ... 62625.html
A growing body of preliminary research suggests the Covid-19 vaccines used in most of the world offer almost no defence against infection by the highly contagious Omicron variant.
All vaccines still seem to provide a significant degree of protection against serious illness from Omicron, which is the most crucial goal. But only the Pfizer and Moderna shots, when reinforced by a booster, appear to have initial success at stopping infections, and these vaccines are unavailable to most of the world.
Easily by now.
https://www.cam.ac.uk/research/news/omi ... y-to-causeOmicron may be significantly better at evading vaccine-induced immunity, but less likely to cause severe disease
[…]
Spike proteins on the surface of SARS-CoV-2 bind to ACE2, a protein receptor found on the surface of cells in the lung. Both the spike protein and ACE2 are then cleaved, allowing genetic material from the virus to enter the host cell. The virus manipulates the host cell’s machinery to allow the virus to replicate and spread.
To see how effective Omicron is at entering our cells, the team used their pseudoviruses to infect cells in lung organoids – ‘mini-lungs’ that model parts of the lung. Despite having three mutations that were predicted to favour the spike cleavage, the researchers found the Omicron spike protein to be less efficient than the Delta spike at cleaving the ACE2 receptor and entering the lung cells.
In addition, once Omicron had entered the cells, it was also less able than Delta to cause fusion between cells, a phenomenon associated with impaired cell-to-cell spread. Fused cells are often seen in respiratory tissues taken following severe disease. Indeed, when the team used a live Omicron virus and compared it to Delta in a spreading infection experiment using lung cells, Omicron was significantly poorer in replication, confirming the findings regarding impaired entry.
Professor Gupta added: “We speculate that the more efficient the virus is at infecting our cells, the more severe the disease might be. The fact that Omicron is not so good at entering lung cells and that it causes fewer fused cells with lower infection levels in the lab suggests this new variant may cause less severe lung-associated disease.
“While further work is needed to corroborate these findings, overall, it suggests that Omicron’s mutations present the virus with a double-edged sword: it’s got better at evading the immune system, but it might have lost some of its ability to cause severe disease.”
However, Professor Gupta urged caution.
“Omicron still represents a major public health challenge. Individuals who have only received two doses of the vaccine – or worse, none at all – are still at significant risk of COVID-19, and some will develop severe disease. The sheer number of new cases we are seeing every day reinforces the need for everyone to get their boosters as quickly as possible.”
https://twitter.com/madsalbertsen85/sta ... 50918?s=21Omicron update from Denmark. 47% of cases were Omicron on the 15th (5-day lag now). Test capacity has been maxed out and DK is adjusting strategy. From now on the key metric is the number of hospitalizations. Using the number of cases as an early indicator is not possible.
Swings and roundabouts, I guess. But that's a small chink of silver lining.“While further work is needed to corroborate these findings, overall, it suggests that Omicron’s mutations present the virus with a double-edged sword: it’s got better at evading the immune system, but it might have lost some of its ability to cause severe disease.”
The virus would probably prefer* not to cause severe disease, because then people wouldn't take so many precautions, and then it could spread even further and faster.raven wrote: ↑Mon Dec 20, 2021 10:44 pmSwings and roundabouts, I guess. But that's a small chink of silver lining.“While further work is needed to corroborate these findings, overall, it suggests that Omicron’s mutations present the virus with a double-edged sword: it’s got better at evading the immune system, but it might have lost some of its ability to cause severe disease.”
Confusingly, my linky from last night is now pointing to today's overview. Should've put a link to the main page instead, like so: COVID-19: Omicron daily overview
https://www.science.org/content/article ... e-judgmentEarly lab studies hint Omicron may be milder. But most scientists reserve judgment
NSW is the ideal setting to measure the severity of Omicron, and it is showing a CFR for Omicron that is <1/2 of Delta
Five reasons it's ideal:
*Prior infection is irrelevant (~2-3% of NSW is prior infected)
*Delta cases were steady through Nov, making a stable baseline CHR
Lots more at the thread.We have observed the aggregate C[H]R fall by ~50% over the last 10 days - what does that mean for the CFR for each Delta case v. Omicron case? We can trace out the relative C[H]R based on the estimated % of cases which were made up of Omicron 5 days ago (& assuming ~0% start of Dec).
I'm tending to think the evidence is starting to show that Omicron is probably less severe, but not sufficiently-less for it to not be serious.Woodchopper wrote: ↑Tue Dec 21, 2021 7:04 pmThread: https://twitter.com/andrewlilley_au/sta ... 91912?s=20
Covers New South Wales.
NSW is the ideal setting to measure the severity of Omicron, and it is showing a CFR for Omicron that is <1/2 of Delta
Five reasons it's ideal:
*Prior infection is irrelevant (~2-3% of NSW is prior infected)
*Delta cases were steady through Nov, making a stable baseline CHRLots more at the thread.We have observed the aggregate C[H]R fall by ~50% over the last 10 days - what does that mean for the CFR for each Delta case v. Omicron case? We can trace out the relative C[H]R based on the estimated % of cases which were made up of Omicron 5 days ago (& assuming ~0% start of Dec).
tl;dr Omicron cases result in about half the hospital admission rate compared to Delta. This ratio isn't confounded by prior infection or differing levels of vaccination.
IMHO he's using a five day lag between a positive test and hospital admission, which may be a bit short. But may not.
I'm tentatively nudging in the same direction. We've got some real world data on infections and some lab results. Its all early days but together they are looking like Omicron isn't as contagious as Delta.jimbob wrote: ↑Tue Dec 21, 2021 7:47 pmI'm tending to think the evidence is starting to show that Omicron is probably less severe, but not sufficiently-less for it to not be serious.Woodchopper wrote: ↑Tue Dec 21, 2021 7:04 pmThread: https://twitter.com/andrewlilley_au/sta ... 91912?s=20
Covers New South Wales.
NSW is the ideal setting to measure the severity of Omicron, and it is showing a CFR for Omicron that is <1/2 of Delta
Five reasons it's ideal:
*Prior infection is irrelevant (~2-3% of NSW is prior infected)
*Delta cases were steady through Nov, making a stable baseline CHRLots more at the thread.We have observed the aggregate C[H]R fall by ~50% over the last 10 days - what does that mean for the CFR for each Delta case v. Omicron case? We can trace out the relative C[H]R based on the estimated % of cases which were made up of Omicron 5 days ago (& assuming ~0% start of Dec).
tl;dr Omicron cases result in about half the hospital admission rate compared to Delta. This ratio isn't confounded by prior infection or differing levels of vaccination.
IMHO he's using a five day lag between a positive test and hospital admission, which may be a bit short. But may not.
Omicron less contagious than Delta? Is that a mistype, or do I misunderstand the meaning of contagious?Woodchopper wrote: ↑Tue Dec 21, 2021 9:15 pm<snnip>
I'm tentatively nudging in the same direction. We've got some real world data on infections and some lab results. Its all early days but together they are looking like Omicron isn't as contagious as Delta.
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