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Faye Flam – Omicron Scrambles What We Know About Immunity. Now What? – Asharq Al-awsat – English

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Forget the debate over how scared we should be of omicron. What matters is putting our energy into solutions that work — taking action that matters on a personal level and demanding effective actions from world leaders.

Scientists are already scrambling to learn how well our existing vaccines will work against this new coronavirus variant. That can help predict how much benefit might come from speeding up worldwide vaccination and booster campaigns, and whether vaccine passports will protect people or give a false sense of reassurance.

Reports that most omicron cases are mild are understandably reassuring for many individuals — especially those of us who aren’t elderly or immunocompromised and have access to booster shots. But some scientists have frowned on such optimism because of the larger picture. If this thing keeps growing exponentially and infects millions of people in a short time, health systems will collapse, even if a tinier fraction of cases are serious.

Cases are rising rapidly in the UK and South Africa, suggesting that omicron has some advantage over delta, the currently dominant coronavirus variant. It might be that it’s inherently more transmissible, or that it’s better able to get past immunity in those who’ve been infected or vaccinated, or some combination of those factors.

Omicron’s genes are weirdly different from previous variants, appearing to be only distantly related to delta. No one is sure where it came from — possibly from growing for months in immune-compromised patients, or from leaping into an animal host and back into humans.

It has 21 mutations in the top part of the spike protein, molecular epidemiologist Emma Hodcroft of the University of Bern said in an interview. Some of these mutations are alarming because they’d been observed in earlier variants that were good at evading immunity from vaccines or past infections.

In just a couple of weeks, scientists have accumulated an impressive amount of preliminary data. Some labs assembled mock versions of omicron by genetically manipulating other variants to carry some of the variant’s key mutations, Hodcroft said. Researchers can grow these “pseudo viruses” in petri dishes and test how well they stand up to antibodies extracted from the blood of vaccinated or previously infected people.

Then last week, a lab in South Africa made headlines with results on the behavior of actual samples of omicron. It found the virus did somewhat evade immunity generated by two shots of the Pfizer vaccine, but was neutralized well by antibodies taken from patients who had been both vaccinated and previously infected with earlier variants. At around the same time, Pfizer announced that antibodies from a booster shot helped stop omicron in laboratory experiments, though the findings aren’t peer reviewed, and outside researchers didn’t get to see the data.

At a press briefing Wednesday, Harvard infectious disease specialist Yonatan Grad said they still don’t know details of any of these experiments. Did the blood come from people who were vaccinated last month or 10 months ago? This matters because other studies demonstrated that antibodies from the Pfizer and Moderna vaccines wane significantly over six to nine months.

“In real humans, it might be more complex, but I think we can probably say that we expect more reinfection or breakthrough infections with omicron than we’ve seen with other variants,” Hodcroft said.

How severe those infections will be isn’t clear. Vaccines (or past infection) leave people with immune cells that hide in the bone marrow and lymph nodes, and these become activated if there’s a new infection and create a bunch of new antibodies. Lab experiments wouldn’t necessarily capture this phenomenon.

With only partial knowledge about the dangers of omicron, wealthy countries such as the US are starting to push harder to get third doses into everyone, though we’d save more lives by getting initial doses to countries with low supplies. Scientists will know a lot more in three or four weeks, when cases of severe disease would be expected to crop up, after omicron has spread and cases have had time to progress, and epidemiologists can measure how fast the variant is expanding outside South Africa.

How and where the disease spreads will depend on past cases in the population, vaccine uptake, seasonal cycles and other factors nobody yet understands. The past behavior has been surprising.

Earlier variants, including alpha, rose fast in the eastern US in the fall of 2020 and then plummeted in the middle of the winter 2021. Those early variants barely touched India, but delta suddenly exploded there in the spring of 2021. That wave, too, crested and fell suddenly.

With omicron, the severity of disease is going to be particularly hard to ascertain without waiting until it infects a sizable number of people of different ages. The original version of SARS-CoV-2 was mild in most people — and it was enormously destructive.

“Even if Omicron has a milder severity — and we don’t know this at the moment — if it spreads really quickly, even a smaller percent of a big number is a big number,” Hodcroft said. “We’re also, in most of the West, fairly ill-prepared for this, since our delta cases are riding so high — we have very little wiggle room left.”

So the best-case scenario would be either that omicron isn’t as transmissible as it first appeared and it fizzles out, or that it’s only little more transmissible than delta and a lot milder — so mild that almost nobody has to be admitted to an ICU.

“It would be the best thing we can hope for,” Hodcroft said, but it’s not something she or other experts are betting on.

Hope is fine as long as it doesn’t lull people into inaction or lessen the sense of urgency. A lot can be done now, including producing omicron-specific vaccines and doing a better job of distributing existing vaccines to the countries that need them most. People need to be ready for more restrictions if the worst-case scenarios play out.

There’s some evidence that vaccinations cut back on transmission. That means the more shots we can get into arms around the world, the fewer chances the virus has to stumble on some new variant — perhaps something that’s not mild at all.

Bloomberg

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U of G to close public COVID-19 vaccine clinic due to high vaccination rates and availability – GuelphToday

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NEWS RELEASE
UNIVERSITY OF GUELPH
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The public COVID-19 vaccination clinic on the University of Guelph campus will close Jan. 21 due to high vaccination rates and greater vaccine availability within the Guelph community.

Since opening Jan. 4, about 9,000 people received vaccine doses at the campus clinic.

“I am delighted and inspired by the enthusiasm and spirit of collaboration that was displayed, once again, by our University and greater Guelph community,” said U of G president Dr. Charlotte Yates.

“People came together under tight time constraints and challenging circumstances to organize and operate our second successful campus vaccination clinic, with many of our faculty, staff and students volunteering their time and expertise. Vaccination is the best way to protect people from the most serious negative health effects of COVID-19, and I am so proud the University was able to help make a difference.”

Run in partnership with Wellington-Dufferin-Guelph Public Health and the Guelph Family Health Team, the clinic was established as part of a community-wide effort to boost vaccination rates and help stem the current pandemic wave.

Held in the W.F. Mitchell gym of the Athletics Centre, the clinic initially saw 1,200 vaccination appointments a day. That number had dwindled to fewer than 100 by late this week, said Christine Zulauf, catering manager with Hospitality Services.

She said the clinic attracted visitors from across the region.

“It’s been a really unique experience to play a role and help get all of these vaccines into the community,” said Zulauf. “Hopefully, it’s a once-in-a-lifetime opportunity and we won’t have to do it again. I’m glad the University was able to help out.”

About 55 volunteers, including staff, faculty and community members, helped direct clinic visitors into and out of the facility. They contributed almost 1,000 volunteer hours in all this month; on average, about 16 volunteers were on hand at the clinic each day.

Many of those volunteers had also helped with the first campus vaccination clinic held for almost five months in 2021. More than 80,000 vaccinations were administered during that earlier five-month clinic.

“It was really wonderful that so many volunteers came back to help us this time around,” said Zulauf.

COVID-19 vaccinations will continue to be offered to faculty, staff and students on campus through Student Health Services.

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'Very nice spring, very nice summer': Omicron will bring us closer to normal, experts say – National Post

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‘We need to lay out a strategy and a plan towards moving back toward something that is nearer normality’

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Anna Bershteyn says there are absolutely no guarantees, of course, but if asked to read the tea leaves, she sees “a very nice spring, a very nice summer, where people can let loose,” see others and not worry so much about COVID-19 .

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It’s just a hope, “but if I had to make a guess, I would say that what Omicron will probably give us is a period of respite,” said Bershteyn, an assistant professor in the department of population health at New York University Grossman School of Medicine. Immunity gained through vaccination, infection or a combination of the two, could move populations closer to controllable levels of COVID, she and other scientists said. The hope is that the virus “sort of vaccinates itself” — that a milder strain gives us immunity to a later, potentially more severe one.

While hospital and ICU numbers are rising nationally, Omicron infections may have peaked and the country could be on a downward slope, federal health officials said Friday.

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COVID is here to stay. SARS-CoV-2 will continue to live in the human population, Dr. Theresa Tam, Canada’s chief public health officer said. While we must prepare for more potential unusual variants, “we do need to lay out a strategy and a plan towards moving back toward something that is nearer normality,” Tam said . In England, mandatory masking in public spaces and vaccine passports will be dropped beginning next week, while Spain is moving toward treating SARS-CoV-2 much like seasonal flu.

Many questions linger: It’s not clear how long immunity to Omicron will last, whether we could see a second wave, or whether infection with a milder stain will indeed provide immunity against whichever Greek letter-named version of SARS-CoV-2 comes next. The virus has already proven whip smart — scientists didn’t see heavily mutated Omicron coming — and it’s still evolving.

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“The big game changer is indeed the moment when nearly everybody will have had some sort of immunity,” Dr. Peter Juni, of Ontario’s COVID-19 science table  recently told a COVID research consortium . “I can’t guarantee endemicity relatively soon, but I can guarantee we can move much closer to endemicity after the Omicron wave.”

Here’s what we know about where we are now and where we need to go.

Rapid rise, rapid descent?

“Our modelling suggests that we are at the peak around now, with some provinces (Ontario and Quebec, which experienced Omicron earliest) just past the peak and others just behind it,” said Caroline Colijn, an associate professor of mathematics at Simon Fraser University and COVID-19 modeller.

In Ontario, the rate of hospitalizations and intensive care admissions is slowing. Restaurants and gyms will reopen starting Jan. 31, with all remaining restrictions to go by mid-March, Premier Doug Ford announced Wednesday. British Columbia is seeing a slowing in transmission rate. “That’s partly the end of the holidays, but I think it partly is  a lot  of people have COVID right now,” said Colijn and that’s having a dampening effect. More people are isolating “or cancelling things if they hear five of their friends have COVID.” That, combined with a shorter course of infections, can drive a speedy decline, she said.

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Our modelling suggests that we are at the peak around now

But Canada might also have a more rounded peak, or double peaks, because of the timing with schools and universities reopening and the lifting of restrictions, Colijn said. “We may not see the very rapid decline that has been seen in South Africa, for example.”

Official case counts are almost irrelevant, with testing systems so overwhelmed. “But it’s important if the number of actual infections happening starts to go down quickly, because that’s going to decrease the burden on everybody — fewer people sick, fewer people in hospital, fewer workplace closures, fewer schools affected,” Colijn said.

Why not just get infected and get it over with?

Famed cardiologist and author Dr. Eric Topol isn’t thrilled with the “Omicron will ultimately find just about everybody,” messaging. “Let’s not invite an unpredictable virus that can cause long COVID,” or secondary attacks, where people who may not be particularly at risk of a bad infection themselves unwittingly pass the virus to someone who can wind up very sick,” Topol said, during a recent University of California, San Francisco Department of Medicine Grand Rounds Q&A. 

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In Australia, “COVID chasers” are hoping to time infections when it’s less inconvenient to isolate. Their thinking runs the lines of, “It’s going to happen anyway, I want to live my life, I’m sick of trying to avoid COVID and it’s likely to be mild in someone like me.”

It’s not a terribly brilliant idea, Topol, founder and director of Scripps Research Translational Institute, and other scientists said. Omicron can cause severe disease. It’s not uniformly mild. With hospitals grappling with shortages of staff and COVID-19 drugs, people who do end up in hospital risk ending up with less-than-optimal care, Juni said. And while it will take months before it’s known whether Omicron can cause long COVID, the phenomenon typically follows mild infections.

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  1. FILE PHOTO: A respiratory therapist and six nurses prone a coronavirus disease (COVID-19) patient inside the intensive care unit of Humber River Hospital in Toronto, Ontario, Canada April 19, 2021.

    Dr. David Jacobs: Omicron has filled up my hospital, but the panic from the Delta wave is gone

  2. Despite some claims, the numbers do indicate that among the elderly, unvaccinated people are much more apt to be made badly sick by the virus.

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  3. A new study found that vaccinated couples were no less likely to conceive than unvaccinated ones.

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Vaccines are still the best shot at making COVID manageable

The vaccines are still holding their own against severe disease with Omicron, and a third dose boosts immunity even higher. Still, demand for third doses appears to be slowing, and while Pfizer has said it should have a vaccine that targets Omicron specifically by March, Topol and others said what’s needed is a universal, “pan” coronavirus vaccine that would protect against all variants and make it harder for the virus to mutate its way around. Omicron proved that SARS-CoV-2 can take huge leaps in evolution, “and get all these mutations all in one jump,” Bershteyn said. “You really can’t place Omicron on the family tree of variants that we’ve seen before. It sort of came out of nowhere, and as far as I can tell there’s no biological rule that says that it couldn’t do this again  and  be very contagious and very deadly at the same time.”

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“The unvaccinated who do not have a boost to their immunity from vaccine are likely to become susceptible again to whatever variant comes next,” she said, and regulatory discussions should be happening now, including, would manufacturers have to do a full clinical trial of a new vaccine, or a small, short trial, looking at the antibody response? How long to monitor for safety? A vaccine against Omicron is three months away. If a more dangerous variant emerged, “we couldn’t wait three months. You’d have to completely lock down everything. It’s just not feasible.”

What’s the endgame?

“Waning immunity and the emergence of new variants will shape the long-term burden and dynamics of COVID-19,” Colijn and colleagues wrote in a pre-print.

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“If we can get another infection in a couple of months, that’s not a good thing for where this virus settles out,” Colijn said. “But if we’re well protected for a year, that’s pretty good news. And what that means is that (COVID) will decline to hopefully pretty low levels and stay at those levels.”

But endemic doesn’t mean “not a problem,” she said. “It just means that it’s stable — it’s not having this huge wave that goes through the population.”

Waning immunity and the emergence of new variants will shape the long-term burden and dynamics of COVID-19

She doesn’t think there’s pressure on the virus to get more severe. Transmission is where the virus is having “its reproductive opportunities. We have the high transmissibility without it carrying along a really high severity. So, hopefully, we don’t get the big, bad new variant,” Colijn said.

Hospitalizations will never be reduced to zero. “There are always going to be frail vulnerable people who succumb to this virus,” McMaster University infectious diseases specialist Dr. Martha Fulford said in an earlier interview. Once past this hump, and with more protection because of boosters, more immunity from infections and more effective treatments, a broader conversation will be needed about the risks posed by COVID and the risks that exist from locking down “forever and a day,” she said.

National Post

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Change to shorter isolation period part of managing COVID 19 in B.C.: top doctor – Vancouver Sun

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Dr. Bonnie Henry says unvaccinated adults who test positive are at risk of having longer-lasting and more severe illness and must isolate for 10 days but those who are vaccinated should isolate for five days.

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VANCOUVER — British Columbia’s top doctor says the current wave of COVID-19 is causing less severe illness and that calls for a shift to shorter periods of isolation in order to minimize societal disruptions.

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Dr. Bonnie Henry says unvaccinated adults who test positive are at risk of having longer-lasting and more severe illness and must isolate for 10 days but those who are vaccinated should isolate for five days.

She says children are at much lower risk of severe illness and are able to clear an infection faster, so five days’ isolation is also suitable for them, with mounting evidence showing they need to interact with others as part of their social development.

Henry says testing is not needed for most people who have symptoms and are likely to have a mild illness but those who are immunocompromised and over 70 could end up with more serious illness and likely need a test.

She says vaccination remains the best protection for everyone, especially for vulnerable groups, but anyone with symptoms should stay home until they feel better, the same as with other respiratory illnesses like the flu.

Henry says COVID-19 is far from being an endemic illness so restrictions that are in place are needed to prevent more hospitalizations, though those numbers have been declining.

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