1539 replies to this topic

[gamesguru]

Yeah that's the article I'm talking about, attached here in HTML because the PDF version on redstate.com has vanished lol.  They literally claimed 100% specificity, like it's a perfect test.  I don't believe it, this virus is brand new to medicine.

 

I haven't seen any conclusive studies yet.  Extraordinary claims require extraordinary evidence.  If we have good reason to fear you're leading us off a cliff, the burden is on you to prove us otherwise.

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•  1 Sol Price School of Public Policy, University of Southern California 2 Schaeffer Center for Health Policy and Economics, Unive.html   20.24KB   2 downloads

[gamesguru]

First confirmed death is now Feb 6 in the Bay area.

 

It's telling how the early shutdown in California—less than a week before NYC—made all the difference in terms of how many died

 

https://www.latimes....-early-february

[albedo]

Important piece of contextual information, paper still in peer-review. It is a study from the small Italian town of Vo which was successful in suppressing the epidemic. They were one of the first in using mass testing and quarantine. "This study sheds new light on the frequency of asymptomatic SARS-CoV-2 infection and their infectivity (as measured by the viral load) and provides new insights into its transmission dynamics, the duration of viral load detectability and the efficacy of the implemented control measures."

 

Suppression of COVID-19 outbreak in the municipality of Vo, Italy

 

On the 21st of February 2020 a resident of the municipality of Vo, a small town near Padua, died of pneumonia due to SARS-CoV-2 infection. This was the first COVID-19 death detected in Italy since the emergence of SARS-CoV-2 in the Chinese city of Wuhan, Hubei province. In response, the regional authorities imposed the lockdown of the whole municipality for 14 days. We collected information on the demography, clinical presentation, hospitalization, contact network and presence of SARS-CoV-2 infection in nasopharyngeal swabs for 85.9% and 71.5% of the population of Vo at two consecutive time points. On the first survey, which was conducted around the time the town lockdown started, we found a prevalence of infection of 2.6% (95% confidence interval (CI) 2.1-3.3%). On the second survey, which was conducted at the end of the lockdown, we found a prevalence of 1.2% (95% CI 0.8-1.8%). Notably, 43.2% (95% CI 32.2-54.7%) of the confirmed SARS-CoV-2 infections detected across the two surveys were asymptomatic. The mean serial interval was 6.9 days (95% CI 2.6-13.4). We found no statistically significant difference in the viral load (as measured by genome equivalents inferred from cycle threshold data) of symptomatic versus asymptomatic infections (p-values 0.6 and 0.2 for E and RdRp genes, respectively, Exact Wilcoxon-Mann-Whitney test). Contact tracing of the newly infected cases and transmission chain reconstruction revealed that most new infections in the second survey were infected in the community before the lockdown or from asymptomatic infections living in the same household. This study sheds new light on the frequency of asymptomatic SARS-CoV-2 infection and their infectivity (as measured by the viral load) and provides new insights into its transmission dynamics, the duration of viral load detectability and the efficacy of the implemented control measures.

[gamesguru]

Contact tracing of the newly infected cases and transmission chain reconstruction revealed that most new infections in the second survey were infected in the community before the lockdown or from asymptomatic infections living in the same household.

 

Quite.  Also noteworthy is the fifth straight day in Vietnam without a new case, they are handling it top notch.. better than Taiwan or the Aussies.

 

Aggressive testing and contract tracing is precisely what is lacking in the US approach.  It is why our numbers continue to spiral out of control, and why states need to tighten their lock-downs and declare independence from the Federal government's feeble efforts to fight the pandemic.  Yesterday we just had our largest number of deaths yet, and the Feds and southern states want to re-open the economy?  They're pushing a right-wing narrative about exaggerated sero-prevalence and herd immunity, and it will cause thousands more deaths.
 

 

As for the % asymptomatic reported in the study?

 

Other studies have reported slightly lower percentages for the prevalence of asymptomatic carriers.  I feel it's around 20%, but that's just my opinion.

 

Our estimated asymptomatic proportion is at 17.9% (95%CrI: 15.5–20.2%), which overlaps with a recently derived estimate of 33.3% (95% confidence interval: 8.3–58.3%) from data of Japanese citizens evacuated from Wuhan [13].

[gamesguru]

Recent Swedish seroprevalence preliminary results retracted.

 

It has emerged that the researchers cannot rule out that a smaller proportion of blood samples were made on people who had covid-19, who donated blood to produce plasma for the treatment of covid patients.

 

Sweden Health Agency Withdraws Controversial Coronavirus Report

 

Uncertain conclusions of the new antibody test [Swedish]

 

 

[Heisok]

My opinion is that California "total" deaths has not come close to peaking. (Not the percentage of those infected which I understand epidemiologically is the important percentage population wise. )

 

In my opinion there is the beginning of a backlash against the extreme projections by the Governor at the beginning. I am going to yell next.    THIS IS NOT A CONSERVATIVE BACKLASH.

 

It is a general population behavior in the Central Valley of California region which I have seen. Maybe 25% wearing masks. Many of those paying lip service to the process by taking them partially off or hanging below their mouth area, so they look like they are being compliant. As far as gloves, it seems like a smaller percentage than the mask wearers, but gloves are not as obvious.  Groups of people walking together or playing basketball in the street with portable equipment. Several adults riding bikes with kids. Maybe a group of 10. They were all close together when they stopped at an intersection. If what I saw continues or spreads (I think it will)  then nothing short of a State crackdown will prevent the total deaths from going far higher.

 

Yesterday, I saw a baseball field where several adults were present, and dragging the dirt infield with the proper equipment to smooth it out. (Official groundskeepers ???) There were also at least 5 or 6 teenagers hanging around together with the adults, apparently waiting to practice.)

 

How have I seen this. I have been biking, but being careful to stay a good distance from others. Far more than 6 feet is easy to maintain where I have been riding. Open streets. (The Governor has all long indicated exercise is OK as long as distance is kept.)

 

(Hi Mind, I saw the direction this thread was currently at, so considered making the above post as it fit. I even looked at yout initial posting, and it did not seem to be against this type of conjecture on my part. If it is an issue, please deal with my post appropriately. Thanks!)

 

 

[gamesguru]

My opinion is that California "total" deaths has not come close to peaking.

 

In my opinion there is the beginning of a backlash against the extreme projections by the Governor at the beginning.

 

You're right the models can't take into account variations in social forces over time, that's why projections change (see below).  And people in California are already tired of the "lockdown", a lot of traffic at Home Depot and such.  The "scenario uncertainty" is often a lot greater than the "scientific uncertainty", and that can wreak havoc on the models.

 

The problem is China and Italy would laugh at the "strictness" of our precautions.  We just had our biggest recorded number of deaths yesterday, and we want to re-open now?  It's an absolute shit show unfolding in real time.

 

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[Mind]

First confirmed death is now Feb 6 in the Bay area.

 

It's telling how the early shutdown in California—less than a week before NYC—made all the difference in terms of how many died

 

https://www.latimes....-early-february

 

If the first victim died on February 6th, that means they were infected in January. Which means the virus was in the U.S. waaaaaay before anyone realized. China let millions of people travel in and out of Wuhan and Hubei and around the world for a month before there was an extreme lockdown. Considering what is known about how fast the virus spreads in unrestricted populations, there seems to be no way it could NOT have travelled around the world a few times before hitting concentrated populations of vulnerable people (Italy).

 

There is no model that would show an infection in California in January - no restrictions until March 17th-19th - and hardly any spread.

 

Considering infections in California in January, the Stanford and USC antibody studies seem to make sense.

[Mind]

Quite.  Also noteworthy is the fifth straight day in Vietnam without a new case, they are handling it top notch.. better than Taiwan or the Aussies.

 

Aggressive testing and contract tracing is precisely what is lacking in the US approach.  It is why our numbers continue to spiral out of control, and why states need to tighten their lock-downs and declare independence from the Federal government's feeble efforts to fight the pandemic.  Yesterday we just had our largest number of deaths yet, and the Feds and southern states want to re-open the economy?  They're pushing a right-wing narrative about exaggerated sero-prevalence and herd immunity, and it will cause thousands more deaths.
 

 

As for the % asymptomatic reported in the study?

 

Other studies have reported slightly lower percentages for the prevalence of asymptomatic carriers.  I feel it's around 20%, but that's just my opinion.

 

20% seems very low considering we have a couple of very good test cases indicating 50% to 60%

 

The Navy ship had 60% asymptomatic cases https://www.business...symptoms-2020-4

 

The Diamond princess had 46.5% asymptomatic cases (and the cases skewed heavily toward elderly adults) https://www.dailymai...ymptomatic.html

 

Italian data shows those with minor or no symptoms comprise 44.2% of the cases. Mild + Minor + Asymptomatic is 79.6% https://www.epicentr...2aprile ENG.pdf

Edited by Mind, 22 April 2020 - 08:57 PM.

[Hebbeh]

It appears people are ignoring that NONE of the testing methods are accurate and appear to all be plagued with some percentage of false positives.  This has been extensively reported and not disputed.  I doubt that there are any so called asymptomatic cases.  That would defy believability and common sense.  More believable is the undisputed reporting of testing unable to differentiate between coronavirus that causes COVID-19 and coronavirus that causes the common cold.

[gamesguru]

If the first victim died on February 6th, that means they were infected in January.

 

There is no model that would show an infection in California in January - no restrictions until March 17th-19th - and hardly any spread.

 

Considering infections in California in January, the Stanford and USC antibody studies seem to make sense.

 

It landed here around January 10th.

 

The first 5% is the slowest.  Look at this University of Toronto model how nothing happens all of November in Wuhan.

 

So you see there's about a 9 week period between patient zero and hospitals reporting ~100 deaths.  If California was seeded in early January, it wouldn't be til March that warning signs would become obvious.  Which is exactly consistent with the true narrative.  Each day lock-down is postponed, exponentially more people die.

 

It doesn't matter even if China had "millions of people travel in and out".  Even if they seeded 170 sick people in Los Angeles, it only speeds up the curve by about 4.5 weeks.

 

If we truly had the months-long head start you're proposing then we would be further along in the exponential curve—we would have actually hit a "logistic" regime—and deaths would slow down instead of spiking in the weeks after the initial warning signs.  The alleged antibody prevalence doesn't make sense on this timeline.

 

The only way to know for sure is to re-open and see.  Looks like Las Vegas wants to make itself a case study, but that may just be a heat of the moment thing.

 

 

The Navy ship had 60% asymptomatic cases https://www.business...symptoms-2020-4

 

The Diamond princess had 46.5% asymptomatic cases (and the cases skewed heavily toward elderly adults) https://www.dailymai...ymptomatic.html

 

That CDC report says Diamond Princess has 46% asymptomatic..

 

But the Eurosurveillance Journal reports under 20% for Diamond Princess.

 

The Italian and Navy ship data are good, but have selection baises.  The Navy ship is young, healthy men mostly.  The Italian data does suggest asymptomatic + paucisymptomatic < 30%, which is understandable given the flexibility of what passes as paucisymptomatic.  The bar between the two—though misplaced—I take to mean 'moderately symptomatic'.

 

Even if there are 40% asymptomatic instead of 20% (which I'm starting to think you're right), it just makes contact tracing and isolation more important.

 

It still does NOT explain these WILD claims that we are only detecting 1 in 85 infections, meaning that LA has close to a million sick, and NYC has many times its own population?  The model literally breaks in New York, I'm expecting more of the same in the largest of its kind, state-wide antibody test starting in NY: either low specificity crippling the significance of the findings, or some other political agenda obviously burying the facts.

Edited by gamesguru, 22 April 2020 - 10:59 PM.

[gamesguru]

It appears people are ignoring that NONE of the testing methods are accurate and appear to all be plagued with some percentage of false positives.  This has been extensively reported and not disputed.  I doubt that there are any so called asymptomatic cases.  That would defy believability and common sense.  More believable is the undisputed reporting of testing unable to differentiate between coronavirus that causes COVID-19 and coronavirus that causes the common cold.

 

This is true of antibody tests, which are generally a blood test.  They can easily confuse similar anti-body proteins and introduce crippling statistical error to the study.

 

But the nasal swab (or saliva) checks for viral mRNA presence in a highly sensitive RT-PCR test.  It is our gold standard.

[Hebbeh]

This is true of antibody tests, which are generally a blood test.  They can easily confuse similar anti-body proteins and introduce crippling statistical error to the study.

 

But the nasal swab (or saliva) checks for viral mRNA presence in a highly sensitive RT-PCR test.  It is our gold standard.

 

Not necessarily. Nasal swab tests are well known and not disputed to come with there own problems.  Even though these issues have been widely reported and I've never viewed any dispute to these issues, It seems few are aware.

 

https://www.contagio...n-elisa-emerges

 

Polymerase chain reaction (PCR) testing for SARS-CoV-2 is currently the most effective frontline test to detect exposure and infection. A positive test, taken from a nasal sample, is presumptive evidence of disease. But a negative test does not rule out infection for a variety of reasons. As many as 25% of the nasal swab tests are likely false negatives.

 

 

https://www.livescie...-negatives.html

 

No diagnostic test is 100% accurate, but experts have still expressed concern at the accuracy of the COVID-19 tests.  Conventional diagnostic tests for the novel coronavirus may give false-negative results about 30% of the time, meaning people with an active COVID-19 infection still test negative for the disease, according to news reports.

 

 

 

https://www.bloomber...-doctors-doubts

 

“Our infectious disease experts think that about 30% of patients we believe have Covid are testing negative,” said Thomas Huth, the health network’s vice president of medical affairs. “We have tested some again, but they remain negative.”

 

 

https://www.fda.gov/...136151/download
 

Negative results do not preclude SARS-CoV-2 infection and should not be used as the sole basis for patient management decisions. Negative results must be combined with clinical observations, patient history, and epidemiological information.

 

 

 

https://www.google.c...iw=1042&bih=477

[gamesguru]

True, it's not so simple.  Stresses the importance of a follow-up test (for those who can afford it)

 

Estimating false-negative detection rate of SARS-CoV-2 by RT-PCR

 

As shown above, the probability of a false-negative test result depends on the number of days since symptom onset. This means that simple reports of positive and negative test counts among individuals who are only tested once will underestimate the true number ofpositive tests in that group. We can illustrate the potential impact this has on averagefalse-negative test rates by supposing that the time from onset of symptoms to testingfollows a gamma-distribution.

 

If we assume further that this distribution is generally representative and does not vary over the course of the epidemic, then we can use it to estimate how many infected individuals are incorrectly identified as uninfected among a group of symptomatic tested individuals who areonly tested once.

 

 

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•  Screenshot_2020-04-22 Estimating false-negative detection rate of SARS-CoV-2 by RT-PCR - 2020 04 05 20053355v2 full pdf.png   291.42KB   0 downloads

[gamesguru]

Cardiovascular damage?

 

Press release

Coronavirus attacks lining of blood vessels all over the body, Swiss study finds

 

Academic study

Endothelial cell infection and endotheliitis in COVID-19

 

Seems to agree with the latest New York data that hypertension is a high risk.

 

And so blood clots are being considered as a potential major factor, despite early reports being dismissed about ibuprofin increasing ACE2 receptor levels (a receptor used by coronavirus).

 

How does coronavirus kill? Clinicians trace a ferocious rampage through the body, from brain to toes

Some clinicians suspect the driving force in many gravely ill patients’ downhill trajectories is a disastrous overreaction of the immune system known as a “cytokine storm,” which other viral infections are known to trigger. Cytokines are chemical signaling molecules that guide a healthy immune response; but in a cytokine storm, levels of certain cytokines soar far beyond what’s needed, and immune cells start to attack healthy tissues. Blood vessels leak, blood pressure drops, clots form, and catastrophic organ failure can ensue.

 

Some studies have shown elevated levels of these inflammation-inducing cytokines in the blood of hospitalized COVID-19 patients. “The real morbidity and mortality of this disease is probably driven by this out of proportion inflammatory response to the virus,” says Jamie Garfield, a pulmonologist who cares for COVID-19 patients at Temple University Hospital.

 

But others aren’t convinced. “There seems to have been a quick move to associate COVID-19 with these hyperinflammatory states. I haven’t really seen convincing data that that is the case,” says Joseph Levitt, a pulmonary critical care physician at the Stanford University School of Medicine.

 

He’s also worried that efforts to dampen a cytokine response could backfire. Several drugs targeting specific cytokines are in clinical trials in COVID-19 patients. But Levitt fears those drugs may suppress the immune response that the body needs to fight off the virus. “There’s a real risk that we allow more viral replication,” Levitt says.

 

Meanwhile, other scientists are zeroing in on an entirely different organ system that they say is driving some patients’ rapid deterioration: the heart and blood vessels.

[gamesguru]

Supposedly random sample of N= ~700 from Sweden showing 2.5% prevalence.  Not an antibody test, this is for virus mRNA.

 

Original link [Swedish]

Randomly recruited people in Stockholm County conducted self-sampling for covid-19 between March 27 and April 3. We use results from this study to calibrate our model and get an estimate of the size of the dark figure.

 

In total, 18 of the 707 people tested were positive in the study. The weighted percentage of positives was 2.5% (95% CI [1.4% - 4.2%]). Assuming that 2.5% of Stockholmers were covid-19-positive between these dates means that a total of 60,455 (95% CI [33,244, 99,731]) people in Stockholm County were positive during this period.

 

We calibrate the parameters and (the proportion of those infected who are unconfirmed cases and the factor that describes how very unconfirmed cases infect in relation to reported cases) in such a way that we get one estimated average prevalence of about 2.5% during the period March 27 - April 3.

 

Why I'm suspicious of this?

• Small sample size
• Potential selection bias (self-reporting candidates)
• Weak inferences drawn from insensitive models (tweaking the "% unreported" parameter to align with the real peak)

It's highly speculative inference.  To say the curves for the 0%, 55% and 98% unreported case rates—which all result in broadly similar curves—somehow offer definitive insight into a real-world scenario that is evolving more rapidly than the scientific models?  It's far-fetched.  Until the analyses are shown more reliable, it's apt to be seen as "massaging the data" to get the facts you want.

[gamesguru]

Breaking news.  I'll report when we know more, I'm already suspicious though

 

NEW: The first phase of results from a statewide antibody study are in.

We collected approximately 3,000 antibody samples from 40 locations in 19 counties.

Preliminary estimates show a 13.9% infection rate.

— Andrew Cuomo (@NYGovCuomo) April 23, 2020

 

He provided some breakdowns.

 

Percent positive by region:

 

Long Island: 16.7%
NYC: 21.2%
Westchester/Rockland: 11.7%
Rest of state: 3.6%

(Weighted results)

— Andrew Cuomo (@NYGovCuomo) April 23, 2020

 

 

Percent positive by demographic:

 

Female: 12%
Male: 15.9%

Asian: 11.7%
Black: 22.1%
Latino/Hispanic: 22.5%
Multi/None/Other: 22.8%
White: 9.1%

(Weighted results)

— Andrew Cuomo (@NYGovCuomo) April 23, 2020

Edited by gamesguru, 23 April 2020 - 03:49 PM.

[Mind]

Breaking news.  I'll report when we know more, I'm already suspicious though

 

 

 

He provided some breakdowns.

 

You seem to disbelieve any data that indicates a lower mortality rate. All of these studies (dozens now) cannot be garbage. Real scientists, real professors, and real epidemiologists in multiple countries are conducting these studies. Are they all dimwits?

[gamesguru]

You seem to disbelieve any data that indicates a lower mortality rate. All of these studies (dozens now) cannot be garbage. Real scientists, real professors, and real epidemiologists in multiple countries are conducting these studies. Are they all dimwits?

 

I demand names.  Which epidemiologists, virologists, or data scientists have actually endorsed any of these reports as water-tight?  Everyone I've spoken to has been extremely skeptical, and we've been following every study.

 

Generic medical doctors on MSNBC are none of the above things.  Take what these media sources say with a grain of salt.  They're Republicans, and the pandemic is just beginning.. it's scary for them.  Think for yourself, form a consensus between experts in specific, relevant fields

[Heisok]

What do  generic medical doctors on MSNBC have to do with Republicans? Which Republicans?

[gamesguru]

What do  generic medical doctors on MSNBC have to do with Republicans? Which Republicans?

 

The same ones that own the media, run Southern states, and are leading their citizens off a cliff as we speak.

 

Florian Krammer and Natalie Dean just expressed doubts.  He's a Professor in the Department of Microbiology

[Mind]

New York study shows widespread antibody prevalence. (FYI, to international readers not a "Southern State")

 

Very similar to the results of other studies in other states and countries (both antibody and active infection testing).

[gamesguru]

New York study shows widespread antibody prevalence. (FYI, to international readers not a "Southern State")

 

Very similar to the results of other studies in other states and countries (both antibody and active infection testing).

 

Yes!  This is the exact study preliminary release we've been discussing for 4 posts.  Welcome to the talk.

 

Chicago Tribunes is a quite factual, slightly right-center source for information.  However it helps when their fans read things before sharing them.

Cuomo cautioned that the data was preliminary. The sample of people tested was small and people were recruited for the study at shopping centers and grocery stores, which meant they were healthy enough to be out in public. [*cough* selection bias]

 

Experts also say having antibodies is not necessarily proof someone is immune from the virus.

[gamesguru]

An updated tweet from the professor of microbiology,

I think this is too high. It is possible. But a 20% plus infection rate seems too high for NYC due to a number of reasons. I would think 6-8%, maybe 10% are closer to the truth. It would be nice to know more about the test, its sensitivity and specificity and the test population.

 

— Florian Krammer (@florian_krammer) April 23, 2020

[gamesguru]

Conservative news outlet urges drastic measures based on new MIT model, which predicts around 2000 deaths daily in America for the next ~3 weeks,

"MIT specifically looked at the virus causing COVID-19. So it's a little bit more accurate."

 

"And what they are showing is we can't just say now we are at the equilibrium or that plateau phase, and now we can start opening," Saphier added.

 

"So we have to be very careful when we are starting to reopen the economy.  But we really need to hunker down."

 

And 88% of people placed on a ventilator do NOT survive, suggesting it's not actually a treatment option, more of a delay,

But the numbers diverge more for the critically ill put on ventilators. Eighty-eight per cent of the 320 Covid-19 patients on ventilators who were tracked in the study died.

[gamesguru]

The NY study also doesn't break down statistics properly.  They tell you what percent of positives were black, white, latino etc, but not what percentage of the sample size those groups made up.  I wish it were easier getting conclusive data on such a scary subject

 

 

More details about it from the Twitter feed.

 

Appears selection bias may be a real problem,

I can tell you that in Saratoga Country there was a Facebook announcement last Sunday that antibody testing was going to happen at a local store for the next three hours. I think people who suspected they were exposed would be more motivated to rush over.

 

The test uses an IgG immunoglobin, with specificity value of 93%.  This introduces a ±7% uncertainty into our positive percentages, because only 93% of patients who are negative will test negative.  The other 7% may have antibodies for a similar cold or flu virus that confuse the test  (Be look for this in the final release)

 

So if we have a low prevalence like 5%, then we get anywhere from 2-12%.  Useless range.

Whereas if the disease is endemic, like planter warts, then we might have a higher prevalence of 70% (most people have had a planter wart) and the error range is only from 63-77% which is a lot more palatable of a range.

[gamesguru]

Gov. Newsom Orders All California Counties To Review Autopsies Dating Back To December

April 23, 2020 8:54 a.m.

 

During Newsom’s press briefing, the governor said that he ordered the counties to do so in order to reach a “deeper understanding of when this pandemic really started to impact Californians” after Santa Clara County public health officials announced on Tuesday that two people had died from the virus earlier than what was previously believed to be the first COVID-19 death in the U.S.

 

According to the Santa Clara officials, the two individuals had died in their homes in early/mid February but had not been recorded as having the virus due to the Centers for Disease Control and Prevention’s (CDC) restrictive requirements for COVID-19 testing at the time.

 

“As the Medical Examiner-Coroner continues to carefully investigate deaths throughout the county, we anticipate additional deaths from COVID-19 will be identified,” they said.

[gamesguru]

Covid-19 causes sudden strokes in young adults, doctors say

The new coronavirus appears to be causing sudden strokes in adults in their 30s and 40s who are not otherwise terribly ill, doctors reported Wednesday.

They said patients may be unwilling to call 911 because they have heard hospitals are overwhelmed by coronavirus cases.

There's growing evidence that Covid-19 infection can cause the blood to clot in unusual ways, and stroke would be an expected consequence of that.

 

Dr. Thomas Oxley, a neurosurgeon at Mount Sinai Health System in New York, and colleagues gave details of five people they treated. All were under the age of 50, and all had either mild symptoms of Covid-19 infection or no symptoms at all.

"The virus seems to be causing increased clotting in the large arteries, leading to severe stroke," Oxley told CNN.

"Our report shows a seven-fold increase in incidence of sudden stroke in young patients during the past two weeks. Most of these patients have no past medical history and were at home with either mild symptoms (or in two cases, no symptoms) of Covid," he added.

 

"All tested positive. Two of them delayed calling an ambulance."

Other doctors have also reported that people are reluctant to call 911 or go to emergency rooms because of the pandemic.

It is not common for people so young to have strokes, especially strokes in the large vessels in the brain.

"For comparison, our service, over the previous 12 months, has treated on average 0.73 patients every 2 weeks under the age of 50 years with large vessel stroke," the team wrote in a letter to be published in the New England Journal of Medicine. That's fewer than two people a month.

 

A stroke in a large blood vessel causes severe damage if it is not removed right away. At least one patient has died, and others are in rehabilitation facilities, intensive care or in the stroke unit. Only one went home but will require intense care, Oxley said.

 

"The average person who has a large vessel stroke is severely impaired," Oxley said. "It means it a bigger clot. It includes one of the largest arteries in the brain."

Brain cells die when blood flow is stopped, and the longer it's blocked, the wider the damage in the brain. Quick treatment is vital. "The most effective treatment for large vessel stroke is clot retrieval, but this must be performed within 6 hours, and sometimes within 24 hours," Oxley said.

 

Oxley said his team wanted to tell people to watch themselves for symptoms of coronavirus infection and to call 911 if they have any evidence of stroke.

"Up until now, people have been advised to only call for an ambulance with shortness of breath or high fever," he wrote.

[xEva]

Was the USC study posted already? It sound very similar to the withdrawn Stanford study, with similar headline: L.A. County Antibody Tests Suggest the Fatality Rate for COVID-19 Is Much Lower Than People Feared

 

Based on that death toll, the new study suggests the true fatality rate among everyone infected by the virus is somewhere between 0.1 percent and 0.3 percent (without taking into account people infected since the study was conducted). The lower end of that range is about the same as the estimated fatality rate for the seasonal flu.

 

Sood addressed two of the methodological concerns that were raised by a recent study of Santa Clara County residents, which likewise estimated that the COVID-19 fatality rate is not far from the rate for the flu. Critics of that study suggested it may have been undermined by biased sampling and false-positive antibody test results.

The sample for the Los Angeles County study, Sood said, was randomly drawn from a database maintained by the LRW Group, a market research firm. The researchers capped subjects representing specific demographic groups so the sample would reflect the county's adult population.

As for the accuracy of the antibody tests, Sood said validation by the manufacturer of the test kits, Premier Biotech, found a false positive rate of 0.5 percent in 371 samples. In subsequent tests by a Stanford laboratory, there were no false positives. "We think that the false positive rate of the tests is really low," Sood said.

 

There is a definitive trend with all these studies, good and not so good. They all converge to a much smaller death rate number, quite in line with our very first reliable data, the Diamond Princess case. 

 

Why do you people insist that it's gotta be worse?

.

[Hebbeh]

Post 450 is this thread already addressed these studies in not so positive but more realistic note (read down to get the real story):

 

https://news.yahoo.c...-161418566.html

New studies suggest huge undercount of coronavirus infections — but are they right?

The number of COVID-19 cases in Los Angeles County may be more than 50 times greater than the official count, according to preliminary results from a new study by the University of Southern California, which estimates that as many as 442,000 adult residents of Los Angeles County may have already been infected.

The implication, as lead USC investigator Neeraj Sood told reporters Monday, is that “the true extent of the infection in our communities” is far greater than previously known.

“We actually found that about 5 percent of Angelenos have in fact, probably, at some time, been infected with COVID-19,” explained Dr. Barbara Ferrer, director of the L.A. County Department of Public Health, which partnered with USC on the study. So now “we are able to understand what the real denominator is” in calculating the rate at which people who are infected develop symptoms, require hospitalization and die.

But should we trust those conclusions?

If accurate, these estimates would fundamentally change our understanding of the coronavirus. Experts have long suspected that real-time testing is only catching a fraction of the total infections. But they have tended to put that fraction somewhere between one in five and one in 20. If in reality we’re only identifying one in 50 infections, or fewer, that would make COVID-19 a lot less deadly than previously believed while also making it a lot more contagious (and asymptomatic “silent carriers” a lot more widespread). That would be a paradigm shift in how to combat the virus.

The problem, though, is that these studies may not be accurate.

Known as a “seroprevalance survey” or “serosurvey,” the preliminary USC study is the second of its kind to come out in the past few days. The first was conducted by Stanford University researchers in Santa Clara County, Calif. — aka Silicon Valley — and released Friday. Together they represent the first attempts at this kind of research in the U.S.

Both serosurveys worked the same way. Researchers recruited hundreds or thousands of local residents to participate. They tried to ensure their “sample” was representative of the county’s overall population. They tested all participants with the same serology test, which is supposed to reveal who has already been infected by detecting antibodies in their bloodstream — even if they never showed symptoms or were never tested for an ongoing infection by the more typical nasal-swab method. Then the researchers tallied up the total number of positive test results, divided it by the total number of participants and “scaled” that percentage to the population of the entire county to estimate the overall seroprevalence of COVID-19 in the area.

Both studies also produced similar — and similarly startling — numbers. In Los Angeles, the USC team found that 4.1 percent of its 863 study participants tested positive; applied to the county as a whole, and adjusted for statistical margin of error, that would mean that anywhere from 2.8 percent (221,000) to 5.6 percent (442,000) of Angelenos have been infected, according to the USC researchers. (By comparison, 423,000 people had tested positive for COVID-19 nationwide as of April 9, when the study concluded.) Meanwhile in Santa Clara, the Stanford team tested 3,330 residents and estimated that 2.5 percent (48,000) to 4 percent (81,000) of the county’s population has been infected — or 50 to 85 times the official number of confirmed cases there.

Yet statisticians and infectious disease experts have been poking holes in the Santa Clara study since the second it came out.

One criticism is that the antibody test they used — a kit purchased from Premier Biotech in Minneapolis — has a false positive rate as high as 1.7 percent, according to some estimates, meaning that even if you test only people who have never had the disease, as many as 1.7 percent of them would still test positive.

To a layperson, that sounds relatively low. But when your sample size is small and the disease you’re testing for is rare, it’s actually big enough to render your results potentially meaningless. Of the 3,330 Santa Clara residents tested, 50 came back positive — or 1.5 percent. Most or all of them, in other words, could have theoretically been false positives.

Another possible issue is the way the researchers “weighted” that raw result, adjusting it statistically to reflect the county’s demographics and account for the inaccuracy of the test. This is how they ultimately estimated that between 2.5 percent and 4 percent of residents have been infected. But as experts have noted, such weighting introduces a lot of subjective judgments that can potentially skew the results — especially when the thing you’re trying to measure has a percentage prevalence in the low single digits.

Statistician John Cherian of D. E. Shaw Research, a computational biochemistry company, made his own calculations given the test’s sensitivity and specificity — and conservatively estimated the proportion of truly positive people in the Stanford study to range from 0.2 percent to 2.4 percent of the Santa Clara population. Adjusting for demographics, Cherian’s calculations suggest that county prevalence could plausibly be under 1 percent.

A final possible sticking point is the sample itself. Participants were asked to volunteer via Facebook ads, meaning, as computational biologist and statistician Balaji S. Srinivasan has explained, that the study might have attracted people who thought they were exposed to the virus and wanted to get a test they couldn’t otherwise get — and that those people might have in turn recruited other exposed people. The result could have been a “biased,” nonrandom sample with more COVID-19-positive participants than the population at large.

The Stanford researchers attempted to account for these issues in their study, and on Sunday they said they are planning to release a detailed appendix that addresses the criticisms and incorporates many of these suggestions into the paper itself.

The USC team did not immediately release their methodology, so it’s difficult to compare their findings to Stanford’s. One difference, according to the lead investigator, was recruitment: Instead of using Facebook, USC called and emailed a random assortment of Angelenos from the database of an L.A. market research firm, then set quotas meant to mimic the demographics of the county as a whole. But it’s entirely possible that many of the potential issues with the Santa Clara study apply here as well. After all, USC used the exact same antibody test, the same lab and many of the same overseeing researchers as Stanford — plus the sample size (863) was much smaller. Neither preliminary study has been peer-reviewed yet.

So how can we know the true extent of the coronavirus pandemic? We can’t — at least not right now. The key is to wait until a bunch of different studies — conducted with different technologies and analytic approaches — come out.

That will happen soon enough. The National Institutes of Health in Bethesda, Md., just launched a serosurvey that will collect and analyze blood samples from as many as 10,000 volunteers. A UC Berkeley project, set to begin in May, will test a large and representative swath of 5,000 East Bay residents. UC San Francisco is now testing all 1,680 residents of rural Bolinas and 5,700 residents of San Francisco’s densely populated and largely Latino Mission District for evidence of the virus. And teams in China, Australia, Iceland, Italy and Germany are expected to release the results of their serosurveys in the coming days.