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Helpful data, or a skewed picture? Coronavirus antibody studies spur debate

Researchers at Stanford and USC suggest that the virus has lower fatality rate

A pair of studies conducted by researchers in Santa Clara and Los Angeles counties drew national attention this week with a finding that COVID-19 is much more widespread — and far less deadly — than public health officials had assumed.

But the studies, which suggested that the fatality rate of COVID-19 could be less than 0.2%, immediately faced a backlash from other scientists, as well as words of caution from public health administrators, who indicated that they will not reopen the economy in a meaningful way any time soon.

The Stanford study, which was led by Assistant Professor Eran Bendavid, asked more than 3,000 volunteers for help in answering a critical question: "How many people in Santa Clara County have been infected by COVID-19?"

Using finger-prick tests and kits that resemble pregnancy tests, the team took blood samples at three drive-thru sites on April 3 and 4, crunched the numbers and published the early draft of the results on a preprint server, giving other researchers a chance to review the results before they are formally published.

In analyzing the blood samples, Bendavid's team found that 50 of 3,330 tested positive for COVID-10, a rate of 1.5%. After adjusting the results to account for precision of tests and sample bias, the study concluded between 48,000 and 81,000 county residents have been infected, a rate of between 2.49% and 4.16%. This led the team to conclude that the number of COVID-19 infections in Santa Clara County is 50 to 80 times higher than the number of confirmed cases.

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The Stanford study calculated the mortality rate of COVID-19 as between 0.12% and 0.2% when one considers the true number of infections. That's far lower than the roughly 4.8% rate one would get by only looking at the county's confirmed cases, which stood at 1,987 as of Thursday afternoon.

The study in Los Angeles, which was undertaken by the University of Southern California and the Los Angeles Department of Public Health, reached a similar conclusion. Led by Neeraj Sood, professor of public policy at USC Price School for Public Policy, the study concluded that between 2.8% and 5.6% of that county's adult population — or between 221,000 and 442,000 adults — have antibodies to the virus.

As the Los Angeles tests were kicking off on April 10, Sood, who collaborated with Stanford researchers on both studies, suggested earlier this month that a far lower fatality rate of COVID-19 would mean that some of the shelter-in-place orders currently in effect may not be necessary.

The Stanford and USC teams are part of a global push to obtain information about COVID-19 through antibody tests — a tool that experts say is critical for learning how the virus spreads and lifting the social-distancing orders that continue to ravage local economies. In Germany and Italy, national governments have made widespread testing a key strategy for easing out of the economic shutdown. Assessing the percentage of the region that has already been infected can help researchers determine how close the area is to herd immunity (a point at which about 60% of the population is immune), which regions have been hit hardest and which measures are going to be most successful in preventing the spread of infections.

"We're starting to get a better picture," said Jay Bhattacharya, professor of medicine at Stanford University and a co-author of both the Stanford and USC studies. "It's clear that it's spread more in some places than in others, and it's clear it's more deadly in some places than others."

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As the shutdown stretches into its second month, seroprevalence studies are becoming increasingly common, both in the Bay Area and around the world. Just this week, a team from the University of California, San Francisco embarked on an effort to provide antibody tests to all residents of Bolinas, an unincorporated community in Marin County. It plans to follow suit on April 25 with a four-day test of about 5,700 residents in San Francisco's Mission District.

Much like its counterparts at Stanford and USC, the UCSF team is trying to address the lack of data about the spread of COVID-19. It is doing so by administering both a swab test for the virus' DNA, which shows whether an individual is currently infected, and a blood-sample test for antibodies, which indicate past infection.

"All our public health decisions, including when it will be possible to relax regional and statewide shelter-in-place orders, are driven by rough assumptions about how the virus behaves based on very limited data," Bryan Greenhouse, an associate professor of medicine at UCSF, said in a news release.

Studying in detail how the virus spreads in Bolinas and in the Mission will "give us crucial data points that we can extrapolate to better predict how to control the virus in similar communities nationwide," he added.

On the national level, the National Institutes of Health is trying to recruit 10,000 people for its own study of antibodies. Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said the study will "give us a clearer picture of the true magnitude of the COVID-19 pandemic in the United States by telling us how many people in different communities have been infected without knowing it because they had a very mild, undocumented illness or did not access testing while they were sick.

"These crucial data will help us measure the impact of our public health efforts now and guide our COVID-19 response moving forward," Fauci said in a statement.

Dr. Sara Cody, Santa Clara County's health official, on Tuesday called the recent seroprevalence tests "exciting" and said that they confirm that "we have many, many, many cases that we didn't pick up."

The point was further underscored by Cody's announcement Tuesday that the county's medical examiner confirmed two deaths from COVID-19 that occurred on Feb. 6 and Feb. 17. The confirmation, based on tissue samples from the deceased, means that the virus was spreading in the community far before the health department became aware of that fact. Prior to the confirmation, county leaders had assumed that the first death associated with COVID-19 occurred on March 9.

But while the new research efforts promise to shed light on the prevalence of COVID-19, public health officials are indicating that they will need far more information before they can think about lifting the restrictions. Cody suggested during her Tuesday update to the Board of Supervisors this week that social-distancing rules are unlikely to be relaxed any time soon.

"We know the level of immunity in our county is in single digits," Cody told the Board of Supervisors on Tuesday. "We are far, far, far from herd immunity and not likely to get there until we have a vaccine."

She also pointed to uncertainty about the large number of antibody tests out on the market, all of which have different characteristics. She cautioned that the detection of antibodies does not necessarily mean that the person is immune to the coronavirus.

"In order to know whether the antibody test indicates that you're protected, there are many more studies that need to be done because basically you have to make sure that the antibody is a marker that you have enough protections such that if you got infected with the virus again you would not get sick," Cody said at the meeting. "Right now, it's not clear whether the antibody tests that are out there provide that."

'Perfect' for task, or a 'screwup'?

While results from both the Stanford and USC studies are preliminary and are now undergoing peer review, the reaction from the scientific community has been swift and, in a few cases, brutal.

Bhattacharya told this news organization Thursday that the team has received more than 1,000 constructive comments on the study, which continues to get refined.

But Andrew Gelman, a professor of statistics and political science at Columbia University, suggested in an online forum that the Stanford authors "owe us all an apology." After detailing his concerns about test accuracy and selection bias, Gelman concluded that the study's findings are a "product of a statistical error."

"I don't think (the) authors need to apologize just because they screwed up. I think they need to apologize because these were avoidable screwups. They're the kind of screwups that happen if you want to leap out with an exciting finding and you don't look too carefully at what you might have done wrong," Gelman wrote.

Other researchers also weighed in and criticized the study for the way it selected its participants (through Facebook ads) and for using tests that were not FDA approved. Dr. Eric Topol, a professor of molecular medicine at Scripps Research, suggested that the two studies have given "a false sense that this is not a bad virus at all."

"It's bad math, bad tests and bad outcomes for the confusion that it engenders," Topol told the Associated Press after the preprint was released.

Bendavid said the research team analyzed the test kits from Premier Biotech before the experiment to determine the percentage of positive cases that the tests miss. By testing blood samples from Stanford Hospital patients that were shown to be positive through a DNA test, as well as samples that were known to be negative because they were taken before the pandemic, the researchers concluded that the test sensitivity is about 91.8%.

Bendavid told this news organization that this was factored into the group's calculation.

"They may be somewhat less precise than laboratory-based tests, but for the purposes of what we have done — for trying to get a sense of prevalence of antibodies to coronavirus in our community — they are perfect," Bendavid said last week.

Part of the skepticism from the broader community stems from the positions that the researchers have taken in the past. In late March, Bendavid and Bhattacharya coauthored an opinion piece in the Wall Street Journal positing that the virus is far less deadly than many experts suggest.

"If it is true that the novel coronavirus would kill millions without shelter-in-place orders and quarantines, then the extraordinary measures being carried out in cities and states around the country are surely justified," Bendavid and Bhattacharya wrote. "But there's little evidence to confirm that premise — and projections of the death toll could plausibly be orders of magnitude too high."

Another member of the Stanford team, John Ioannidis, wrote an article in March suggesting that the true fatality rate of COVID-19 could be 0.05%, lower than the seasonal influenza. If that is the real rate, "Locking down the world with potentially tremendous social and financial consequences may be totally irrational.

"It's like an elephant being attacked by a house cat. Frustrated and trying to avoid the cat, the elephant accidentally jumps off a cliff and dies," Ioannidis wrote in Stat, a health news website.

Sood also said earlier this month that if tests show that the death rate of COVID-19 is indeed nine or 10 times that of the flu, people should indeed stay at home and practice "very strong physical distancing," according to a news release from USC.

But if the true mortality rate is far lower than the flu, he wrote, "then we don't need to be doing that."

(Infectious-disease expert Fauci said in March that the seasonal flu has a mortality rate of 0.1%. However, it should be noted that more than 100 million Americans get the flu vaccine annually, according to the CDC, and no such vaccine exists for the coronavirus.)

But researchers also emphasized that the mortality rate of the virus is not the only factor that should be considered by public health officials as they consider their next steps in managing the pandemic. The findings in Los Angeles showing that about 4% of the population is infected mean that "we are very early in the epidemic and many more people in Los Angeles County could potentially be infected."

"And as the number of infections arise, so will the number of deaths, the number of hospitalizations and the number of ICU admissions," Sood said in a news conference Monday.

Bhattacharya shared that view. The biology of the virus, he told this news organization, is not the only factor that determines the fatality rate. Another key factor is the setting in which patients that get viral pneumonia are treated.

"It's a very important input into the decision, but it's not the only thing," Bhattachary said of the death rate. "How likely is it, if we lift the caps, that we will overwhelm the hospitals? That's a really important question that needs to be addressed."

Given the outstanding questions, county and state leaders are continuing to take a cautious approach on social-distancing orders. Santa Clara County Executive Jeff Smith pointed to the recent discovery of February deaths from COVID-19 as another reason to proceed slowly.

"It's all consistent with what we know," Smith said. "There's a larger population in the community that is infected than we are currently identifying with testing, and a significant portion of that population is asymptomatic as far as COVID — another reason to recognize the great risk we have by relaxing the shelter-in-place too early."

And while some governors are already restarting their states' economies, Gov. Gavin Newsom said California's stay-at-home order would only be modified based on numerous indicators. These include expanded testing and contact tracing, the ability of hospitals to handle surges and the development of treatments.

In his Wednesday address, Newsom highlighted the Stanford and the USC studies, noting that they have "generated a little bit of controversy about what they are and what they're not."

But he also said that the state is preparing to greatly expand its use of serological tests to manage the COVID-19 crisis, noting that the state has agreed to buy 1.5 million such tests from Abbott Laboratory.

"While it (serological testing) can be extraordinarily helpful in terms of guiding our framework and indicators for reopening, it is not at this moment a panacea, but it could be profoundly significant," Newsom said. "And we will certainly do our part, in addition to procuring PCR (diagnostic DNA) tests, we will do the same to provide serology tests to people all over the state," Newsom said.

Find comprehensive coverage on the Midpeninsula's response to the new coronavirus by Palo Alto Online, the Mountain View Voice and the Almanac here.

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Helpful data, or a skewed picture? Coronavirus antibody studies spur debate

Researchers at Stanford and USC suggest that the virus has lower fatality rate

by / Palo Alto Weekly

Uploaded: Fri, Apr 24, 2020, 7:02 am

A pair of studies conducted by researchers in Santa Clara and Los Angeles counties drew national attention this week with a finding that COVID-19 is much more widespread — and far less deadly — than public health officials had assumed.

But the studies, which suggested that the fatality rate of COVID-19 could be less than 0.2%, immediately faced a backlash from other scientists, as well as words of caution from public health administrators, who indicated that they will not reopen the economy in a meaningful way any time soon.

The Stanford study, which was led by Assistant Professor Eran Bendavid, asked more than 3,000 volunteers for help in answering a critical question: "How many people in Santa Clara County have been infected by COVID-19?"

Using finger-prick tests and kits that resemble pregnancy tests, the team took blood samples at three drive-thru sites on April 3 and 4, crunched the numbers and published the early draft of the results on a preprint server, giving other researchers a chance to review the results before they are formally published.

In analyzing the blood samples, Bendavid's team found that 50 of 3,330 tested positive for COVID-10, a rate of 1.5%. After adjusting the results to account for precision of tests and sample bias, the study concluded between 48,000 and 81,000 county residents have been infected, a rate of between 2.49% and 4.16%. This led the team to conclude that the number of COVID-19 infections in Santa Clara County is 50 to 80 times higher than the number of confirmed cases.

The Stanford study calculated the mortality rate of COVID-19 as between 0.12% and 0.2% when one considers the true number of infections. That's far lower than the roughly 4.8% rate one would get by only looking at the county's confirmed cases, which stood at 1,987 as of Thursday afternoon.

The study in Los Angeles, which was undertaken by the University of Southern California and the Los Angeles Department of Public Health, reached a similar conclusion. Led by Neeraj Sood, professor of public policy at USC Price School for Public Policy, the study concluded that between 2.8% and 5.6% of that county's adult population — or between 221,000 and 442,000 adults — have antibodies to the virus.

As the Los Angeles tests were kicking off on April 10, Sood, who collaborated with Stanford researchers on both studies, suggested earlier this month that a far lower fatality rate of COVID-19 would mean that some of the shelter-in-place orders currently in effect may not be necessary.

The Stanford and USC teams are part of a global push to obtain information about COVID-19 through antibody tests — a tool that experts say is critical for learning how the virus spreads and lifting the social-distancing orders that continue to ravage local economies. In Germany and Italy, national governments have made widespread testing a key strategy for easing out of the economic shutdown. Assessing the percentage of the region that has already been infected can help researchers determine how close the area is to herd immunity (a point at which about 60% of the population is immune), which regions have been hit hardest and which measures are going to be most successful in preventing the spread of infections.

"We're starting to get a better picture," said Jay Bhattacharya, professor of medicine at Stanford University and a co-author of both the Stanford and USC studies. "It's clear that it's spread more in some places than in others, and it's clear it's more deadly in some places than others."

As the shutdown stretches into its second month, seroprevalence studies are becoming increasingly common, both in the Bay Area and around the world. Just this week, a team from the University of California, San Francisco embarked on an effort to provide antibody tests to all residents of Bolinas, an unincorporated community in Marin County. It plans to follow suit on April 25 with a four-day test of about 5,700 residents in San Francisco's Mission District.

Much like its counterparts at Stanford and USC, the UCSF team is trying to address the lack of data about the spread of COVID-19. It is doing so by administering both a swab test for the virus' DNA, which shows whether an individual is currently infected, and a blood-sample test for antibodies, which indicate past infection.

"All our public health decisions, including when it will be possible to relax regional and statewide shelter-in-place orders, are driven by rough assumptions about how the virus behaves based on very limited data," Bryan Greenhouse, an associate professor of medicine at UCSF, said in a news release.

Studying in detail how the virus spreads in Bolinas and in the Mission will "give us crucial data points that we can extrapolate to better predict how to control the virus in similar communities nationwide," he added.

On the national level, the National Institutes of Health is trying to recruit 10,000 people for its own study of antibodies. Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said the study will "give us a clearer picture of the true magnitude of the COVID-19 pandemic in the United States by telling us how many people in different communities have been infected without knowing it because they had a very mild, undocumented illness or did not access testing while they were sick.

"These crucial data will help us measure the impact of our public health efforts now and guide our COVID-19 response moving forward," Fauci said in a statement.

Dr. Sara Cody, Santa Clara County's health official, on Tuesday called the recent seroprevalence tests "exciting" and said that they confirm that "we have many, many, many cases that we didn't pick up."

The point was further underscored by Cody's announcement Tuesday that the county's medical examiner confirmed two deaths from COVID-19 that occurred on Feb. 6 and Feb. 17. The confirmation, based on tissue samples from the deceased, means that the virus was spreading in the community far before the health department became aware of that fact. Prior to the confirmation, county leaders had assumed that the first death associated with COVID-19 occurred on March 9.

But while the new research efforts promise to shed light on the prevalence of COVID-19, public health officials are indicating that they will need far more information before they can think about lifting the restrictions. Cody suggested during her Tuesday update to the Board of Supervisors this week that social-distancing rules are unlikely to be relaxed any time soon.

"We know the level of immunity in our county is in single digits," Cody told the Board of Supervisors on Tuesday. "We are far, far, far from herd immunity and not likely to get there until we have a vaccine."

She also pointed to uncertainty about the large number of antibody tests out on the market, all of which have different characteristics. She cautioned that the detection of antibodies does not necessarily mean that the person is immune to the coronavirus.

"In order to know whether the antibody test indicates that you're protected, there are many more studies that need to be done because basically you have to make sure that the antibody is a marker that you have enough protections such that if you got infected with the virus again you would not get sick," Cody said at the meeting. "Right now, it's not clear whether the antibody tests that are out there provide that."

'Perfect' for task, or a 'screwup'?

While results from both the Stanford and USC studies are preliminary and are now undergoing peer review, the reaction from the scientific community has been swift and, in a few cases, brutal.

Bhattacharya told this news organization Thursday that the team has received more than 1,000 constructive comments on the study, which continues to get refined.

But Andrew Gelman, a professor of statistics and political science at Columbia University, suggested in an online forum that the Stanford authors "owe us all an apology." After detailing his concerns about test accuracy and selection bias, Gelman concluded that the study's findings are a "product of a statistical error."

"I don't think (the) authors need to apologize just because they screwed up. I think they need to apologize because these were avoidable screwups. They're the kind of screwups that happen if you want to leap out with an exciting finding and you don't look too carefully at what you might have done wrong," Gelman wrote.

Other researchers also weighed in and criticized the study for the way it selected its participants (through Facebook ads) and for using tests that were not FDA approved. Dr. Eric Topol, a professor of molecular medicine at Scripps Research, suggested that the two studies have given "a false sense that this is not a bad virus at all."

"It's bad math, bad tests and bad outcomes for the confusion that it engenders," Topol told the Associated Press after the preprint was released.

Bendavid said the research team analyzed the test kits from Premier Biotech before the experiment to determine the percentage of positive cases that the tests miss. By testing blood samples from Stanford Hospital patients that were shown to be positive through a DNA test, as well as samples that were known to be negative because they were taken before the pandemic, the researchers concluded that the test sensitivity is about 91.8%.

Bendavid told this news organization that this was factored into the group's calculation.

"They may be somewhat less precise than laboratory-based tests, but for the purposes of what we have done — for trying to get a sense of prevalence of antibodies to coronavirus in our community — they are perfect," Bendavid said last week.

Part of the skepticism from the broader community stems from the positions that the researchers have taken in the past. In late March, Bendavid and Bhattacharya coauthored an opinion piece in the Wall Street Journal positing that the virus is far less deadly than many experts suggest.

"If it is true that the novel coronavirus would kill millions without shelter-in-place orders and quarantines, then the extraordinary measures being carried out in cities and states around the country are surely justified," Bendavid and Bhattacharya wrote. "But there's little evidence to confirm that premise — and projections of the death toll could plausibly be orders of magnitude too high."

Another member of the Stanford team, John Ioannidis, wrote an article in March suggesting that the true fatality rate of COVID-19 could be 0.05%, lower than the seasonal influenza. If that is the real rate, "Locking down the world with potentially tremendous social and financial consequences may be totally irrational.

"It's like an elephant being attacked by a house cat. Frustrated and trying to avoid the cat, the elephant accidentally jumps off a cliff and dies," Ioannidis wrote in Stat, a health news website.

Sood also said earlier this month that if tests show that the death rate of COVID-19 is indeed nine or 10 times that of the flu, people should indeed stay at home and practice "very strong physical distancing," according to a news release from USC.

But if the true mortality rate is far lower than the flu, he wrote, "then we don't need to be doing that."

(Infectious-disease expert Fauci said in March that the seasonal flu has a mortality rate of 0.1%. However, it should be noted that more than 100 million Americans get the flu vaccine annually, according to the CDC, and no such vaccine exists for the coronavirus.)

But researchers also emphasized that the mortality rate of the virus is not the only factor that should be considered by public health officials as they consider their next steps in managing the pandemic. The findings in Los Angeles showing that about 4% of the population is infected mean that "we are very early in the epidemic and many more people in Los Angeles County could potentially be infected."

"And as the number of infections arise, so will the number of deaths, the number of hospitalizations and the number of ICU admissions," Sood said in a news conference Monday.

Bhattacharya shared that view. The biology of the virus, he told this news organization, is not the only factor that determines the fatality rate. Another key factor is the setting in which patients that get viral pneumonia are treated.

"It's a very important input into the decision, but it's not the only thing," Bhattachary said of the death rate. "How likely is it, if we lift the caps, that we will overwhelm the hospitals? That's a really important question that needs to be addressed."

Given the outstanding questions, county and state leaders are continuing to take a cautious approach on social-distancing orders. Santa Clara County Executive Jeff Smith pointed to the recent discovery of February deaths from COVID-19 as another reason to proceed slowly.

"It's all consistent with what we know," Smith said. "There's a larger population in the community that is infected than we are currently identifying with testing, and a significant portion of that population is asymptomatic as far as COVID — another reason to recognize the great risk we have by relaxing the shelter-in-place too early."

And while some governors are already restarting their states' economies, Gov. Gavin Newsom said California's stay-at-home order would only be modified based on numerous indicators. These include expanded testing and contact tracing, the ability of hospitals to handle surges and the development of treatments.

In his Wednesday address, Newsom highlighted the Stanford and the USC studies, noting that they have "generated a little bit of controversy about what they are and what they're not."

But he also said that the state is preparing to greatly expand its use of serological tests to manage the COVID-19 crisis, noting that the state has agreed to buy 1.5 million such tests from Abbott Laboratory.

"While it (serological testing) can be extraordinarily helpful in terms of guiding our framework and indicators for reopening, it is not at this moment a panacea, but it could be profoundly significant," Newsom said. "And we will certainly do our part, in addition to procuring PCR (diagnostic DNA) tests, we will do the same to provide serology tests to people all over the state," Newsom said.

Find comprehensive coverage on the Midpeninsula's response to the new coronavirus by Palo Alto Online, the Mountain View Voice and the Almanac here.

Comments

Moot
Another Palo Alto neighborhood
on Apr 24, 2020 at 9:34 am
Moot, Another Palo Alto neighborhood
on Apr 24, 2020 at 9:34 am

This article must have been written before the New York study came out with similar information.

Web Link

One fifth of New York was already infected. This is a bizarre virus that just doesn't affect everyone the same way, and symptoms may not even be apparent.


Anon
Another Palo Alto neighborhood
on Apr 24, 2020 at 9:46 am
Anon, Another Palo Alto neighborhood
on Apr 24, 2020 at 9:46 am

IF the results of the now-three studies turn out to be statistically sound (that is controversial), Santa Clara County is still far from a herd immunity level, as noted in the article:

"We are far, far, far from herd immunity and not likely to get there until we have a vaccine."

It may be that New York City is at or near that level, where there will be a decline just because so many people already have antibodies. The thing is, I really don't want to go through what those folks in New York City have been through.


Dan
Professorville
on Apr 24, 2020 at 10:27 am
Dan, Professorville
on Apr 24, 2020 at 10:27 am

The most important thing from all these studies is clearning up misinformation about the true fatality rate of Covid. Most news sources have been terribly misleading by reporting the number of "cases", which is defined as people who have tested positively, not people who were actually infected. This is terribly misleading as it drastically overstates the fatality rate of the disease.

Recall the media has been talking about a 3% fatality rate, and implying that 3% of people who get infected die. The reality that they should have been reporting on is 3% of people who were so sick that they went to the hospital and were actually able to get tested went on to die.

The new antibody studies all show that the actual fatality rate is more like 0.1% to 0.2% of people who become infected. Said another way, 1 or 2 people out of every 1,000 people infected who will die.

This number needs to be further drilled down on, because it's not evenly distributed across the population. If you are younger than 50, and you don't have underlying conditions, the actual chance of you dying from Covid is extremly low - like less than one in ten thousand, or even less than one in one hundred thousand if you are younger than 30 and healthy. If you are in one of the highest risk groups, then your risk may be more like 1 percent.

As we get more and more data like this, it should help us all be more informed about the risks to both us and to our fellow citizens. It should also inform our policy as we begin restart our economy - it's pretty clear that in the short term the high risk groups still need to be protected and to take serious precautions. But for the lower risk groups, we probably need to be more focused on making sure they do not transmit the disease to higher risk groups than on protecting themselves.

The prevalence data is a different discussion, with different policy implications - about 5% in Santa Clara have already contracted and recovered from Covid, and about 20% in Manhattan - which shows we have a long way before we get to herd immunity.


Other Tom
Downtown North
on Apr 24, 2020 at 10:51 am
Other Tom, Downtown North
on Apr 24, 2020 at 10:51 am

Really? The conclusions of the study may or may not be valid, but you can't tell from the incredibly flawed study. 3600 self selected people from facebook who knew they would be tested for having had COVID. Don't you think those who have been sick would sign up more than the average joe? And there were only 50 positives. Pretty small and very skewed sample. They really should apologize.


Dan
Professorville
on Apr 24, 2020 at 11:11 am
Dan, Professorville
on Apr 24, 2020 at 11:11 am

Hi "other Tom"

I think that is a very reasonable question to ask about just the single Stanford study, but multiple studies around the world are starting to come back with similar data. In the United States the studies done in New York and in Los Angeles by USC all point to very similar conclusions.

All we can do at any point in time is act on the best data we have. The good news is that our visibility into this disease and pandemic is getting clearer almost every day, and we can all use it to inform our actions.


Gale Johnson
Adobe-Meadow
on Apr 24, 2020 at 11:50 am
Gale Johnson, Adobe-Meadow
on Apr 24, 2020 at 11:50 am

I will probably never feel comfortable/relaxed dining out with my lady friend, Dona, again and that has always been a special time for us. We have been dining out together for several years and and we select restaurants each time with different ethnic foods and from different countries. We have 19 of those under our belts. At one time the fabulous food was really under our belts and in our tummies. When the relaxation starts to include local restaurants I might get my enthusiasm built back up a little bit, but it will never be the same...masked servers wearing gloves will be a new experience...and not one I'm looking forward to.

I have had the thrilling experience of having a Caesar Salad prepared/tossed at our table, and the Steak Dianne flamed at our table. At the table now means at least 6 feet away. That's not really 'at your table'. Close and within viewing distance of the show, but not right at our table.


rita vrhel
Crescent Park
on Apr 24, 2020 at 12:11 pm
rita vrhel, Crescent Park
on Apr 24, 2020 at 12:11 pm

Interesting studies. Yes, self selection is not a randomized study. Will be fascinating to see what additional scientifically conducted studies reveal.
The final and correct answer is a long way off.I hope the results do not deter officials from restoring our shameful Public Health System and planning for the next pandemic; which we know will occur.

In the meantime; we are best to be safe and follow the State and Country guidelines.


Sophie
Another Palo Alto neighborhood
on Apr 24, 2020 at 12:37 pm
Sophie, Another Palo Alto neighborhood
on Apr 24, 2020 at 12:37 pm

From the result of their blood survey, the German team estimated the death rate in the municipality at 0.37% overall, a figure significantly lower than what’s shown on a dashboard maintained by Johns Hopkins, where the death rate in Germany among reported cases is 2%.

Web Link


Sophie
Another Palo Alto neighborhood
on Apr 24, 2020 at 12:40 pm
Sophie, Another Palo Alto neighborhood
on Apr 24, 2020 at 12:40 pm
Robert
Mountain View
on Apr 24, 2020 at 1:07 pm
Robert, Mountain View
on Apr 24, 2020 at 1:07 pm

I've already expressed my concerns about sample bias, particularly in the Stanford study that solicited donors on Facebook, word of mouth, and TV news to a lesser extent. I see these findings, if confirmed to be approximately true, are both good news and bad news.

The good news would be 1) the death rate MAY be a at least an order of magnitude lower than previously thought, and 2) we could be well on the way to "herd immunity". Note that authorities in Sweden, which took a more passive approach and let the infection spread, said this week that they are approaching the beginnings of herd immunity.

The bad news would be that people who are susceptible due to other serious pre-existing medical conditions (comorbidities), must continue to exercise extreme caution because there will be a significant of fraction of asymptomatic "silent carriers" who can infect them. Any easing of shelter in place regulations must be designed to protect these most vulnerable people.

And this is where the need for "unlimited" on-demand cheap and fast viral testing comes in --- and we're months away from that under any reasonable scenario.


KrozNest
Old Palo Alto
on Apr 24, 2020 at 1:19 pm
KrozNest, Old Palo Alto
on Apr 24, 2020 at 1:19 pm

It sounds as if there may have been irregularities in the way the recruitment was done for this study.

See:
Web Link


What Will They Do Next
Old Palo Alto
on Apr 24, 2020 at 1:50 pm
What Will They Do Next, Old Palo Alto
on Apr 24, 2020 at 1:50 pm

Dr. Sara Cody, Santa Clara County's health official stated,"We are far, far, far from herd immunity and not likely to get there until we have a vaccine."

It's important for people to understand that vaccination in and of itself, does not equate to immunity. If it were true that it did, we would no longer have a myriad of diseases that specific vaccines were developed to prevent.

While it is also true that some vaccines have had great success (smallpox, polio and a few others), the majority have not eradicated the diseases they were intended to. Jonas Salk (polio vaccine) was said to have stated that the vaccine itself didn't eliminate polio, but it was developed at a time when greatly improved sanitary and hygienic measures were being practiced in the U.S., which he believed contributed to its' overall success.

Robert, who posted above makes a very valid point when he says that "people who are susceptible due to other serious pre-existing medical conditions (comorbidities), must continue to exercise extreme caution because there will be a significant fraction of asymptomatic "silent carriers" who can infect them. Any easing of shelter in place regulations must be designed to protect these most vulnerable people."

And for the rest of us, lifting the shelter in place restrictions should begin soon with judicious precautions being practiced by the most vulnerable, who most likely know they fit the category and can do much to self protect.


Johnny
Midtown
on Apr 24, 2020 at 2:04 pm
Johnny, Midtown
on Apr 24, 2020 at 2:04 pm

When the infection rate is low, the false positive will make the study results unreliable. if the false positv rate is 2%,then most the positive results in the Stanford and LA sdudies may be false. The anit body test will only be useful when the infection rate is at least 3,4 fold higher than the false positive rate. If you use New York City study, positive is about 20% and fatality is about 0.7%.


Resident
Downtown North
on Apr 24, 2020 at 2:10 pm
Resident, Downtown North
on Apr 24, 2020 at 2:10 pm

Sample selection was poorly done. Self selected people from Facebook advertisement. That's a very small potential group of folks. That already is statistically not representative of the population.


Dave Wiltsee
another community
on Apr 24, 2020 at 3:52 pm
Dave Wiltsee, another community
on Apr 24, 2020 at 3:52 pm

The notorious Carnival cruise ship which spread the virus early has now reported the following: 2596 confirmed cases; 65 deaths. That would seem to be a reasonable "control group", although the close proximity of those affected over the period of several weeks might exaggerate both figures applied to the broader community. On the other hand, at this time we do not know the outcome for those confirmed positives who have not (yet) died.

Still, these statistics indicate a death rate of 2.5%, considerably higher than either study cited here.


ASR
College Terrace
on Apr 24, 2020 at 3:58 pm
ASR , College Terrace
on Apr 24, 2020 at 3:58 pm

We need solid recommendations on what to do to be safe.

If we need to social distance for years to come, we need to know.

If we shouldn’t eat animals we need to know.


Resident
Midtown
on Apr 24, 2020 at 5:59 pm
Resident, Midtown
on Apr 24, 2020 at 5:59 pm

One idea that hasn't been explored, so far as I know, is that small herds can develop herd immunity a lot more quickly than large herds. If a city like NYC has enough smaller living units, for example, that means an appreciable section of the population is already immune, thereby reducing the threshold for overall herd immunity. If NYC has a 20% infection rate it may have already reached its herd immunity level.


Sophie
Another Palo Alto neighborhood
on Apr 24, 2020 at 6:17 pm
Sophie, Another Palo Alto neighborhood
on Apr 24, 2020 at 6:17 pm

Bret Stephens in the NYT:

As of Friday, there have been more Covid-19 fatalities on Long Island’s Nassau County (population 1.4 million) than in all of California (population 40 million).
Yet Americans are being told they must still play by New York rules — with all the hardships they entail — despite having neither New York’s living conditions nor New York’s health outcomes. This is bad medicine, misguided public policy, and horrible politics.


Web Link


Boho
Greenmeadow
on Apr 24, 2020 at 6:22 pm
Boho, Greenmeadow
on Apr 24, 2020 at 6:22 pm

You could be forgiven for thinking that the media is rooting for this to be worse than it actually is.


Barron Park dad
Barron Park
on Apr 24, 2020 at 10:20 pm
Barron Park dad, Barron Park
on Apr 24, 2020 at 10:20 pm

Is this true? Is so, the Stanford study could be very flawed.

BuzzFeed News: A Stanford Professor’s Wife Recruited People For His Coronavirus Study By Claiming It Would Reveal If They Could “Return To Work Without Fear”

Web Link


Barron Park dad
Barron Park
on Apr 24, 2020 at 10:25 pm
Barron Park dad, Barron Park
on Apr 24, 2020 at 10:25 pm

“Bhattacharya has also been making the rounds of conservative media. Here he is on Tucker Carlson a week ago saying that the COVID19 death rate is ‘likely orders of magnitude lower’ than previously thought.”

Web Link


JA3+
Crescent Park
on Apr 25, 2020 at 12:13 pm
JA3+, Crescent Park
on Apr 25, 2020 at 12:13 pm

"About 6 percent of Miami-Dade’s population — about 165,000 residents — have antibodies indicating a past infection by the novel coronavirus, dwarfing the state health department’s tally of about 10,600 cases, according to preliminary study results announced by University of Miami researchers Friday."

Web Link


rld
another community
on Apr 26, 2020 at 7:44 pm
rld, another community
on Apr 26, 2020 at 7:44 pm

We do not seem to have age-stratified results for the SCC and LA serum antibody studies, and maybe not the Heinesburg Germany study either.

It is possible that various age groups have different infection prevalences.

Also, the infection fatality rate being reported is the aggregate, and we know that younger groups have lower case fatality rates, so they probably also have lower infection fatality rates. It is easy to imagine that subpopulations such as younger people without comorbidity will have extremely low IFR, even in the range of seasonal flu.

So, one can imagine that younger healthy people may choose to or be allowed to reach herd immunity. The age boundary might be relatively high, depending on the IFR based on age.


In an article in Vox.com, the SCC and LA tests did not stratify for age:

About the SCC study:
'The study also didn’t control for age. “The overall effects of such biases is hard to ascertain,” authors wrote.'

Web Link


Anon
Another Palo Alto neighborhood
on Apr 27, 2020 at 10:07 am
Anon, Another Palo Alto neighborhood
on Apr 27, 2020 at 10:07 am

Posted by rld, a resident of another community

>> Also, the infection fatality rate being reported is the aggregate, and we know that younger groups have lower case fatality rates, so they probably also have lower infection fatality rates. It is easy to imagine that subpopulations such as younger people without comorbidity will have extremely low IFR, even in the range of seasonal flu.

It is somewhat surprising to me that the politically "conservative" opinion seems to be "get back to business as normal", even though we now know that policy would have a life-expectancy-shortening effect on older people. I can understand a starving tribe of hunters-gatherers asking the old people to sacrifice themselves for the sake of their grandchildren. It is kind of surprising to ask presumably respected elders to sacrifice themselves now, with vast amounts of food available for everyone, so that people can go back to eating out, going to bars, going to sports events, and other ways of spending discretionary income.

The presumably low "overall death rate" that the conservative media are touting conceals a very large impact on seniors, but, I guess that is OK with "conservatives".

Instead, how about we figure out how to continue running, or, re-start, the engines of actual productivity, and, learn to live without rubbing shoulders with each other as much. Zoom, Skype, Facetime, Webex, Microsoft Teams, etc., private offices for office workers with private filtered air, etc, etc. We don't need to cough on each other to get productive work done.


John Mamin
St. Claire Gardens
on May 23, 2020 at 12:07 pm
John Mamin, St. Claire Gardens
on May 23, 2020 at 12:07 pm

I don’t know if it is the reporter who wrote the article, or the researchers who did the study, but somebody seems unclear on the concept of significant figures. It makes no sense to give infection rates to three significant figures (“between 2.49% and 4.16%”) when the uncertainty is that large. Also, how could the true fatality rate be 0.05%? Maybe this was plausible in March, but with nearly 100,000 deaths in the US to date, even if half the country were already infected, the inferred rate would still be higher.


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