Calls to pursue herd immunity are 'callous, dangerous nonsense': immunologist

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Calls to pursue herd immunity are 'callous, dangerous nonsense': immunologist
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A proposal to abandon lockdown policies and allow COVID-19 to run unchecked in the population is gathering steam in the U.S. But experts warn it is a dangerous idea that would overwhelm health-care systems and lead to high numbers of deaths. (Blvdone/Shutterstock)
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A U.S. proposal that calls for an end to lockdowns and for people to try to achieve herd immunity is raising alarm bells among health experts who say such a move would have devastating consequences.

"It's callous, dangerous nonsense," said John Moore, a microbiologist and immunologist at Weill Cornell Medical Center in New York City.

"One of the problems with mathematical modelling is the phenomenon of garbage in, garbage out. And if you put in the parameters of your model incorrectly, you get unreliable answers," he told The Current's Matt Galloway.

"Even if they were correct, the human cost of doing what they propose to do is terrible."

The Great Barrington Declaration, which was drafted in early October by a group of scientists in Massachusetts, argues that lockdown policies are wreaking havoc on people's health and well-being. It instead calls for focused measures to protect "the vulnerable" from COVID-19, while allowing those "at minimal risk of death" to return to normal life and build up herd immunity to the virus.

The New York Times has reported that the White House supports the idea, and according to the declaration's website, the proposal has garnered hundreds of thousands of signatures. However, few of those names have been made public.

Herd immunity happens when a significant portion of the population is exposed to a virus and it can no longer spread because people have become immune to it. This is typically what occurs when a significant portion of the population is vaccinated against a disease. But experts largely agree it can't be achieved safely with COVID-19, for which there is no vaccine yet. Dr. Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases in the U.S, dismissed the idea on Thursday, calling it "dangerous."

Moore said that to achieve herd immunity this way, around 70 per cent of the population would need to become infected. However, a study published last month in the Lancet found that less than 10 per cent of Americans formed COVID-19 antibodiesduring the first wave of the pandemic.

Letting the virus run wild could lead to millions of deaths, Moore said, not to mention long-term health consequences and financially crippling medical bills that can come with being hospitalized in the U.S.

"So we don't buy it. We don't buy this argument," he said. "We think it's just wrong."

Death, long-term health consequences likely
Another problem with the Great Barrington Declaration is the question of how to determine who is "vulnerable," says Ashleigh Tuite, an infectious disease epidemiologist and mathematical modeller at the University of Toronto, who uses models to project the spread of communicable diseases.

Even if society was to isolate everyone over the age of 65, that would account for almost 20 per cent of Canadians, she said.

"You're talking about a huge segment of the population who you're first of all, saying, you know, you have to stay in isolation while we run this terrible experiment out," Tuite said.

"And then you also have the collateral damage of, you know, all of these other people who you identified as non-vulnerable … some of whom will die, some of whom will have consequences of infection, including long-term consequences."

This idea of being able to protect [the] vulnerable is not practical or feasible or ethical.- Ashleigh Tuite, infectious disease empidemiologist and mathematical modeller
She said she doesn't think the idea of herd immunity could be carried out without overwhelming the health-care system and causing a significant number of deaths.

"This idea of being able to protect [the] vulnerable is not practical or feasible or ethical," said Tuite.

The declaration is also based on a "false premise" that governments and scientists want lockdowns to continue, she added.

On the contrary, experts are seeking "the least bad approach" to tackling COVID-19, Moore said.

"This is not something that has a simple overnight solution. The long-term solution is an effective vaccine," he said. "In the meantime, people need to do the obvious, which is social distance and mask-wearing. And in America, unfortunately … it's a political issue."

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An electron microscope image shows the SARS-CoV-2 virus particles, orange, isolated from a patient. Ashleigh Tuite, an infectious disease epidemiologist and mathematical modeller, says letting COVID-19 run rampant would cause 'collateral damage.' (NIAID/National Institutes of Health via The Associated Press)
Declaration 'facilitates more polarization'
Tim Caulfield, Canada research chair in health law and policy, and a professor at the University of Alberta, stressed that the Great Barrington Declaration is a "relatively fringe perspective" and not a "dominant theme in the academic literature."

"One of the things I'm worried about is there's going to be this false-balance discussion going on more broadly in pop culture — that on the one hand we have the Barrington perspective, and on the other hand we have full lockdown," he said.

But it's not a binary discussion, he said. Around the world, governments are trying to adopt an approach to COVID-19 that accounts for both the economy and people's health.

"But unfortunately what a document like this does is it really facilitates more polarization in the public discourse," said Caulfield. "I worry it's going to result in more people becoming cynical spreaders … where they're not going to wear their masks."

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Samples from coronavirus vaccine trials are handled inside the Oxford Vaccine Group laboratory in England, on June 25. Microbiologist and immunologist John Moore says there is no 'overnight solution' to the pandemic. 'The long-term solution is an effective vaccine,' he says. (John Cairns, University of Oxford/The Associated Press)
Tuite said people are tired and frustrated with the pandemic, and what the Great Barrington Declaration offers is a simple solution.

But letting it play out would be "an utter disaster."

"I think the one thing that the declaration has right is that we do need to protect our most vulnerable," Tuite said.

"But we also need to do this in a manner that invests in our public health infrastructure, that, you know, considers measures that will control transmission in the broader population … and look to other countries who have done this."

She pointed to New Zealand, Vietnam and Japan as examples of success stories, where life has somewhat returned to normal.

"There is a way to get through this, to navigate the next little while, that doesn't require lockdowns and doesn't require us throwing up our hands and saying, well, the virus wins, that we need to just let it circulate in our population," said Tuite.

Written by Kirsten Fenn. Produced by Rachel Levy-McLaughlin, Julie Crysler and Marc Apollonio.
 
赞同这文章观点。上次那几个说不用戴口罩的“doctor”,就跟我们那经常遇到的白痴一个德行,特别是第一个那个女的。很有意思哈,床铺的粪们都有点这类:shy:
 
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