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A rare clotting disorder may cloud the world's hopes for AstraZeneca's COVID-19 vaccine – Science Magazine

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A man receives a dose of AstraZeneca’s COVID-19 vaccine at a conference center in Rome on 24 March. Italy halted use of the vaccine on 15 March but resumed immunizations four days later.

Antonio Masiello/Getty Images

Science’s COVID-19 reporting is supported by the Heising-Simons Foundation.

In the tumultuous rollout of AstraZeneca’s COVID-19 vaccine, all eyes were on the United States this week, where the company had a highly public communication breakdown over the vaccine’s efficacy with an expert panel overseeing a large study in the Americas. But on the other side of the Atlantic, the vaccine faces new concerns about safety as an explanation gains ground for the unusual strokes and clotting disorders recorded in at least 30 recipients.

Many European countries suspended use of AstraZeneca’s vaccine earlier this month following initial reports of the symptoms, which have led to at least 15 deaths. Most resumed vaccinations after the European Medicines Agency (EMA) recommended doing so on 18 March, saying the benefits of the vaccine outweigh any risks. EMA is continuing to investigate the matter and will convene a wideranging committee of experts on 29 March.

Now, a group of researchers led by German clotting specialist Andreas Greinacher of the University of Greifswald says the highly unusual combination of symptoms—widespread blood clots and a low platelet count, sometimes with bleeding—resembles a rare side effect of the blood thinner heparin, called heparin-induced thrombocytopenia (HIT).

The scientists, who first described their findings during a 19 March press conference, recommend a way to test for and treat the disorder and say this can help ease worries about the vaccine. “We know what to do: how to diagnose it, and how to treat it,” says Greinacher, who calls the syndrome vaccine-induced prothrombotic immune thrombocytopenia, or VIPIT. Greinacher says he has submitted a manuscript to the preprint server Research Square.

Even if Greinacher’s mechanism isn’t the whole story, multiple researchers told Science they were convinced that the vaccine was causing the rare set of symptoms. If that turns out to be true, it could have major consequences for the vaccine, which is one of the cornerstones of the World Health Organization’s push to immunize the world. AstraZeneca is working with partners around the globe to make and distribute billions of doses in low- and middle-income countries, which might have a harder time identifying and treating rare side effects.

Europe is relying heavily on the vaccine as well; the European Union bought 400 million doses. The company’s failure to deliver on time has delayed vaccine rollouts on the continent, but now, dented confidence is exacerbating the delays. And even if the risk is very low, it may make sense to use the vaccine only in those who also stand to gain the most from it: elderly people at high risk of dying from COVID-19. Several European countries have started to do this. The situation has scientists walking a tightrope: They want to make the medical profession aware of their concerns without sowing panic.

But Greinacher’s hypothesis is being taken seriously. Two German medical societies put out press releases lauding him for solving the issue. In the Netherlands, the Dutch Internal Medicine Society urged internists to be aware of the symptoms and the recommended course of action. The United Kingdom has officially reported only 5 cases—despite administering 11 million doses of the AstraZeneca vaccine—but the British Society of Haematology has urged its members to be aware of “an important and emerging area of haemostasis and thrombosis practice” and to report any possible cases. The Australian Technical Advisory Group on Immunisation has recommended against giving any COVID-19 vaccine to people with a history of HIT.

It is not yet clear how the vaccine could trigger VIPIT, and not everyone thinks the case is closed. “It’s intriguing, but I am not entirely convinced,” says Robert Brodsky, a hematologist at Johns Hopkins University. AstraZeneca, meanwhile, has not directly responded to the reports of the rare constellation of symptoms except to say that they did not appear in any of the company’s clinical trials.

“People are absolutely working like crazy behind the scenes to provide more clarity,” says Saskia Middeldorp, a vascular internist at Radboud University Medical Center in the Netherlands, who disagreed with the temporary halt of the vaccine because she says the benefits clearly outweigh the risks.

A ‘very striking’ disorder

The VIPIT story began on 27 February, when Sabine Eichinger, a hematologist at Medical University Vienna, was confronted with an unusual patient. A 49-year old nurse had sought help at a local hospital the day before, suffering from nausea and stomach discomfort, and was transferred to Eichinger’s hospital. She had a low platelet count and computed tomography scans found thromboses—blood clots—in the veins in her abdomen and later in arteries as well. “There was little we could do at this stage,” says Eichinger. The patient died the next day.

The combination of low platelet count, or thrombocytopenia, and clots kept Eichinger thinking, however. “It’s very striking,” she says. Platelets, also known as thrombocytes, help to form blood clots, so low levels usually lead to bleeding, not clotting. “You would think that low platelets and thromboses are opposites really.” One condition where they occur together is called disseminated intravascular coagulation, when severe infection, injury, or cancer trigger clotting so widespread it uses up all the platelets, “but she had none of these things,” Eichinger says.

The unusual combination also appears in HIT, which can occur in patients given heparin as a drug. Heparin binds to a protein called platelet factor 4 (PF4), forming a complex. For reasons that aren’t understood, some people produce antibodies against the complex, setting off an out-of-control clotting reaction. Eichinger’s patient had not received heparin, but she had gotten a shot of the AstraZeneca vaccine 5 days before her symptoms began. “I thought maybe this is some kind of immune reaction,” Eichinger says.

She reached out to Greinacher, who had studied HIT for decades. “Then things started happening thick and fast,” she says, as multiple countries responded to reports of clotting by suspending use of the AstraZeneca vaccine.

Greinacher says he contacted other colleagues who had studied HIT in Canada and Germany and asked the Paul Ehrlich Institute (PEI), which oversees vaccine safety in Germany, if they had seen any cases. They had. PEI recommended that Germany pause use of the vaccine as well and asked Greinacher to help investigate. He soon received blood samples from eight additional patients. All had both low platelets and unusual clotting, he says. In four samples, the researchers also found evidence for antibodies against PF4, a hallmark of HIT. He and his colleagues are now checking whether other vaccine recipients and former COVID-19 patients have similar antibodies.

People are absolutely working like crazy behind the scenes to provide more clarity.

Saskia Middeldorp, Radboud University Medical Center

Brodsky says it isn’t clear whether VIPIT explains all of the cases. He agrees that the PF4 antibodies and the clotting seen in patients resemble HIT, but the link has not been proven, he says: “I’m convinced that these patients have platelet factor 4 antibodies, at least four of them. But I’m not convinced that those … antibodies are explaining the thrombocytopenia or the clotting.”

Treatable condition

Greinacher agrees on the need for more data. But he says it’s crucial to alert doctors to the potential complication. When recognized in time, HIT can be treated with immunoglobulins—nonspecific antibodies from blood donors—that help put the brakes on platelet activation. Non-heparin blood thinners can help dissolve the clots. VIPIT should be treated in a similar way, he says. In at least one case, Greinacher says, a doctor sought the group’s advice and the patient recovered. The German Society for the Study of Thrombosis and Hemostasis, of which Greinacher is a member, has issued a set of recommendations for diagnosing and treating VIPIT. Greinacher says he has also been in touch with safety representatives at AstraZeneca.

Nigel Key, a hematologist at the University of North Carolina at Chapel Hill, agrees on the need to alert doctors. “Maybe it is too much to expect at this point that there would be a very detailed molecular mechanism,” he says, but the advice to physicians who may encounter patients is crucial.

Brodsky and Key say the cases are striking enough that they probably represent a real side effect. “I think the vaccine is mostly safe. I think the benefits probably outweigh the risk for a general population,” Brodsky says. “But these cases raise concern that this vaccine is potentially life-threatening in a small subset of patients.”

Scientists are now scrambling to understand how big that subset is and who’s in it. So far, most cases have been observed in women under 65. But that could be because of the vaccinated population: Many countries initially used AstraZeneca only in people under 65 because early clinical trials included few older recipients. That meant the vaccine was used in priority groups such as health care workers and teachers, a majority of whom are women. In Norway, for example, 78% of the AstraZeneca doses went to women, says Sara Viksmoen Watle, chief physician at the Norway Institute of Public Health. The United Kingdom, however, used the vaccine first in older people, which may explain why fewer unusual clotting events have been spotted there.

Data from Norway—whose extensive health registries make this type of research easier—suggests previous COVID-19 infection does not predispose vaccinees to a severe reaction, Watle says. Alerting clinicians will help ensure that fewer cases are missed for analysis, Key says. A global database of cases may be helpful too.

Many countries are, for now, accept the risk that the AstraZeneca may carry, but several have restricted its use to people who are at the highest risk of dying from COVID-19: those aged 55 or older in France, 65 or older in Sweden and Finland, and 70 or older in Iceland. That approach makes sense, says Sandra Ciesek, a virologist at Goethe University Frankfurt. “The argument I keep hearing is that the risk-benefit ratio is still positive. But we do not have just one vaccine, we have several. So restricting the AstraZeneca vaccine to older people makes sense to me, and it does not waste any doses.”

Denmark and Norway are waiting for more data. Norway, which has administered the AstraZeneca vaccine to 130,000 people under 65, has reported five patients who had low platelets, hemorrhage, and widespread thromboses, three of whom died. That’s about one case in 25,000 vaccinees, “a high number with a very critical outcome in previously healthy, young individuals,” says Watle. The country hopes to make a decision on the vaccine within 3 weeks. It can afford to hold off: COVID-19 cases are relatively low and AstraZeneca is delivering so few doses that the extended pause won’t make a big difference in the short-term.

Middeldorp says she expects more clarity after Monday’s meeting of EMA’s expert group, which includes clotting experts, neurologists, virologists, immunologists and epidemiologists. The agency says it will issue an update on the vaccine during the next meeting of its safety committee, being held from 6 to 9 April. Ideally that meeting will help clarify how frequently the condition occurs and whether the risk varies by age or sex, Middeldorp says. The world needs AstraZeneca’s vaccine, she says—but that means it is crucial to fully understand its benefits and its risks.

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COVID-19: Ottawa adult vaccinations at 69 per cent; Ontario reports 192 new cases – Ottawa Citizen

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Ottawa Public Health reported Friday that 69 per cent of adults in the capital are fully vaccinated.

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According to the OPH vaccination dashboard, updated Friday morning, 591,639 people aged 18 and over have the two shots.

In all, 83 per cent of the population 12 years and older has received one dose.

Seven new cases of COVID-19 were reported in Ottawa on Friday, bringing the total number of cases since the pandemic began to 27,268.

The death toll remains unchanged at 593.

Ottawa Public Health knows of 41 active cases in the region. However, there are no COVID-19 patients in hospital.

In indicators of interest, the rolling seven-day average of cases per 100,000 residents is 3.9, while the populations per cent positivity in testing is 0.5.

The reproductive number, the average number of people that one infected person will pass on a virus to, is 1.28.

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Latest COVID-19 news in Ottawa

Ontario reported 192 new confirmed cases of COVID-19 and one new death on Friday.

While it’s the second week the province’s numbers have been below 200, confirmed cases have climbed significantly from Monday, when 130 new cases were reported.

Currently, there are 137 people in hospital in Ontario, with 136 in ICU due to COVID-related illness and 84 on a ventilator. (Ontario Public Health statistics of ICU hospitalizations and ventilator cases contain some patients who no longer test positive for COVID-19 but who are being treated for conditions caused by the virus.)

There have been 548,986 confirmed cases and 9,308 deaths since the pandemic began.

In health regions in the Ottawa area, Renfrew and District reported three new cases. There were no new cases reported in the Eastern Ontario Health Unit, Kingston or Leeds, Grenville and Lanark units.

Latest COVID-19 news in Quebec

Quebec reported 101 new cases of COVID-19 and one more death Friday morning.

Hospitalizations in the province declined by four patients, for a total of 67. The number of cases in ICU were unchanged at 21.

The province administered 94,624 additional vaccine doses were administered over the previous 24 hours.

Since the beginning of the pandemic, Quebec has reported 376,530 cases and 11,239 deaths linked to COVID-19.

Latest COVID-19 news in Canada

Canada’s Chief Public Health Officer Dr. Theresa Tam reported Friday that 46.7 million doses of vaccine have been administered in Canada, and more than 60 per cent of people over the age of 12 have been fully vaccinated.

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Dutch Teen Who Went to Space With Jeff Bezos Told Him He’s Never Bought Anything on Amazon – Gizmodo

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New Shepard lifts off from Launch Site One in West Texas with four humans on board. (July 20, 2021)

The award for “Best Small Talk on a Flight to Space” goes to Oliver Daemen, the 18-year-old from the Netherlands who was part of Blue Origin’s inaugural crewed flight to space earlier this week. On the roughly 10-minute flight, Daemon told Amazon founder Jeff Bezos what probably sounded like blasphemy to his billionaire ears: He had never bought anything on Amazon.

In an interview with Reuters on Friday, Daemen recounted his first flight to space, from when he got the call asking him if he was interested to the conversations he had with his crewmates, which included Bezos, his brother Mark Bezos, and 82-year-old pilot Wally Funk. Daemen, whose father is the CEO of a private equity firm in the Netherlands, became the youngest person to ever fly to space, while Funk became the oldest.

The teen also holds the distinction of surprising Bezos, whose Amazon empire has made him one of the richest men in the world.

“I told Jeff, like, I’ve actually never bought something from Amazon,” Daemen told Reuters. “And he was like, ‘oh, wow, it’s [been] a long time [since] I heard someone say that.’”

Considering that Bezos thanked “every Amazon employee and every Amazon customer” for making the flight possible after he and the crew returned to Earth, Daemen’s comments may have been a little awkward. However, it’s nice (and kind of funny) to hear that someone was frank with him. Bezos no doubt has enough people telling him that Amazon is God’s gift to humanity, so it’s cool to see one of the youths set him straight.

Daemen wasn’t originally supposed to go on the flight with Bezos and crew. He was offered the opportunity after the winner of the online auction for the seat, whose identity is still unknown and who paid a whopping $28 million for it, said they couldn’t go because of “scheduling conflicts.” Daemen, who was a participant in the auction and had already secured a spot on the second flight, was then moved up on the list. His father, Joes Daemen, paid for the seat.

According to Daemen, his family didn’t pay anything near what the mysterious bidder paid for the opportunity.

“We didn’t pay even close to $28 million, but they chose me because I was the youngest and I was also a pilot and I also knew quite a lot about it already,” he said.

The teen, who will begin his studies at Utrecht University in September, said he wasn’t sure what he wanted to do professionally, but would consider focusing on space travel. He also told the outlet that his fellow travelers were “super fun and all down to Earth.” Well, considering Daemen’s referring to a man that wants to stupidly move all polluting industry into space, I’m not sure I’m sold on that.

Congratulations on the award for that great small talk, though.

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Several Ontario mass vaccination clinics wind down as focus shifts to smaller sites – CP24 Toronto's Breaking News

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The Canadian Press


Published Friday, July 23, 2021 1:37PM EDT


Last Updated Friday, July 23, 2021 1:37PM EDT

Several mass COVID-19 vaccination clinics across Ontario are winding down as first-dose registrations wane and communities shift their focus to smaller venues.

The large clinics held in local arenas, hospitals and recreation centres across the province have been a key part of the vaccine rollout that began in the winter.

Now that first-dose vaccination coverage has hovered at around 80 per cent for adults provincewide, many health units are beginning the transition to smaller, more targeted vaccination approaches.

“Our large-scale clinics are ending because they are no longer filling up,” the Northwestern Health Unit, which covers the city of Kenora, Ont., and surrounding communities, said in a statement this week as its mass clinics wrapped up operations. “Once they are over, we will provide the vaccine in our offices and at smaller clinics in the community.”

Grey Bruce, a current hot spot for the more infectious Delta COVID-19 variant, is also shutting down its mass clinics at the end of the month to return the large sites for community use.

The health unit is advising people with shots booked for August and beyond to reschedule, and is offering smaller clinics across the region that includes several rural areas.

People living in the Wellington-Dufferin-Guelph region were urged this week to seek out their shots before the local health unit starts closing mass clinics the week of Aug. 6.

“I encourage people to take advantage of the thousands of available appointments at our clinics before we move to the next phase,” Rita Isley, director of community health for the region, said in a statement. “These last few weeks of our mass clinics are the easiest way to get your shot.”

The health unit said it will shift to small clinics and pop-ups “into the fall” after the last of the large clinics close on Aug. 20.

Larger cities are also following the trend, with Mississauga, Ont., aiming to close a convention centre used as a vaccination site on Monday, with another hospital clinic closing the next day.

Mayor Bonnie Crombie said the transition away from mass clinics is part of the city’s focus on bringing vaccines to the least-immunized communities, with more emphasis planned on pop-ups, drive-thru clinics and primary care sites.

“This is a good news story and it shows that our mass vaccination clinics have done their job getting the majority of our people vaccinated,” Crombie told reporters on Thursday.

“We can now look at this period as the home stretch of our initial vaccine rollout to get to that final 10 to 20 per cent of our population and ensure that they, too, are vaccinated.”

​Kingston, Ont.’s health unit announced last week that it would enter a “new phase” of its vaccination effort, with plans to shut down mass clinics beginning in August and shift to pharmacy, mobile and primary care sites.

Mass clinics in the London, Ont., will see reduced hours in the coming weeks amid dwindling demand, the health unit announced this week. It said immunizations have sped up and many people have moved up their second-dose appointments that were scheduled for the fall, meaning the large sites won’t be needed.

“As the health unit turns its focus to individuals in the community, the vaccination effort will rely on mobile and walk-in pop-up clinics, as well as providing opportunities to be vaccinated at community events,” the Middlesex-London Heath Unit said in a statement.

Health Minister Christine Elliott said earlier this month that primary care sites would become more essential to the province’s vaccination plan as mass clinics at hospitals, stadiums and other large venues wind down and resume their old uses.

A spokeswoman for Elliott said targeted vaccination strategies will play a greater role going forward as the province aims to reach vaccine hesitant communities.

“The province is working with the public health units to improve vaccination rates through mobile clinics and community-based pop-ups, dedicated clinic days for people with disabilities, holding townhall meetings in multiple languages, and providing services such as transportation, translation services, and drive-through clinics,” Alexandra Hilkene said in a statement on Friday.

The Grey Bruce health unit noted this week that its local COVID-19 situation is now a “pandemic of the unvaccinated,” a trend documented around the world.

The health unit says 95 per cent of cases reported in the first two weeks of July were among people not fully vaccinated, and encouraged people to get their shots, noting that it’s likely that vaccinated people may be subject to fewer restrictions such as isolation rules in the event of future outbreaks.

“Vaccinating the majority of people sets us on the road to return to normal,” it said.

Ontario reported 192 new COVID-19 cases on Friday and one death from the virus. Sixty-six per cent of Ontario adults are now fully vaccinated.

This report by The Canadian Press was first published July 23, 2021.

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