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Friday, August 6, 2021

Social network for doctors is full of vaccine disinformation

 Dr. Paul Malarik, a retired psychiatrist, now spends about 50 hours a month helping to administer Covid-19 vaccines at pop-up clinics near his home in San Luis Obispo, California. So he’s particularly troubled when he logs onto Doximity, a site used by doctors, and reads anti-vaccine comments.

“You rarely get to the level of microchips in vaccines, but a lot of this stuff is pretty close to it,” said Malarik, who volunteers his time to mix vaccines, put shots in arms and educate the public. “They’re actively working against us.”

Doximity, which has long described itself as LinkedIn for doctors, held its stock market debut in June and rocketed up to a $10 billion market cap. In its IPO prospectus, the company said it had 1.8 million members, including 80% of physicians across the U.S. They use the site to connect with one another, share research, stay informed on industry trends and securely communicate with patients.

Malarik, who worked in psychiatry for over two decades, said it’s baffling to peruse Doximity’s site and find the type of misinformation that he expects to see on Facebook and YouTube, where conspiracy theories run rampant.

Malarik read directly from several comments posted by people with the initials M.D. or D.O., which indicates doctor of osteopathic medicine, after their names. There’s no anonymity on the site, so everyone is identified. In the posts, they refer to the vaccines as experimental, unproven or deadly and occasionally write “Fauxi” when talking about Dr. Anthony Fauci, the White House chief medical advisor.

Some commenters say that antibodies from contracting Covid are more effective than the messenger RNA, or mRNA, vaccines, which instruct human cells to make specific proteins that produce an immune response to the disease.

While the mRNA vaccines for Covid-19 are currently on the U.S. market under emergency use authorizations from the Food and Drug Administration, clinical trials have proven that they’re highly effective against Covid-19. The FDA and the Centers for Disease Control and Prevention said they are safe, effective and recommended for everyone 12 and older, even for those who have had the virus. President Joe Biden and CDC Director Dr. Rochelle Walensky have described the current situation as a “pandemic of the unvaccinated.”

As Malarik scrolls down the Doximity news feed, he stops on a New York Times story from June that’s still featured prominently on his page. The headline reads, “A judge dismisses Houston hospital workers’ lawsuit about vaccine mandates.”

Below the article, hundreds of Doximity users posted comments. Here’s what a surgeon wrote:

“Covid-19 vaccines have already killed over 4,000 adults who’ve received the vaccine,” the post said, appearing to mimic a debunked claim made by Fox News host Tucker Carlson. “To mandate a vaccine that has already killed over 4,000 is akin to murder.”

It’s not an outlier. Dozens of screenshots and descriptions of posts shared with CNBC by other doctors were consistent with Malarik’s experience. Articles about vaccines or masks have hundreds of comments, many that are factually inaccurate and often based on conspiracy theories, while stories on less politically divisive topics have just a few comments, if any at all.

“Everyone is jumping on the articles they can fight about,” Malarik said.

Shares of Doximity were down more than 5% on Friday morning.

The content moderation conundrum

For Doximity, which stayed largely under the radar prior to its IPO, medical misinformation presents a distinct challenge as the San Francisco-based company seeks to grow its user base and remain a source for high-quality reliable data while also navigating the tricky waters of content moderation.

Doximity is scheduled to report quarterly earnings next week for the first time since going public, following a year of 77% revenue growth. The company has been profitable each of the last three years by keeping down operating costs.

Doximity is not an open social network: To join, users must be practicing U.S. health-care professionals. The company verifies members by photo identification of a medical license, a hospital badge, emails from medical institutions and through challenge questions, among other methods.

Like LinkedIn, the company makes money through sponsored content and from recruiters, who use the site to find talent. Because Doximity is entirely focused on medical professionals, the marketing dollars come largely from drug companies and hospitals targeting relevant users with treatments and services, including through sponsored articles and animated videos on the news feed. More than 80% of Doximity’s revenue in its last fiscal year came from its marketing products.

Unlike LinkedIn, Facebook, Twitter and other popular social media platforms, Doximity doesn’t allow users to post stories. The company posts articles from mainstream news outlets and medical and science publications, and every user’s feed is customized based on area of medical practice and other personal details.

“Our platform uses both algorithms and clinical editors to select content from a variety of sources based on a member’s profile and reading interests,” the company said in its prospectus. “We are able to aggregate connections to relevant content from a variety of different sources, such as medical journals and specialist websites that a member might otherwise have to search for separately.”

One added draw is that users can earn continuing medical education credits by reading certain eligible articles. Some states require doctors to obtain a specified number of credits each year to keep their licenses.

However, users are allowed to comment on these stories — and that’s where medical misinformation can proliferate. On the same news feed as those articles, users are finding an abundance of commentary that’s anything but educational.

For example, a recent article on masking mandates for kids caught the ire of some of the same doctors who oppose the vaccines. A general surgeon commented that “masking children is absolutely ridiculous and a form of child abuse.” Another said that “50 years of data accumulated by the CDC and [World Health Organization] demonstrated those masks to have made no difference. None.”

Scientists and public health organizations have repeatedly said that masks can help slow the spread of Covid-19. The rise of the delta variant and resurgence in hospitalizations across parts of the country led several states to reinstitute mask mandates.

Doximity has rules that should put a lid on misinformation. In its community guidelines, the company lists 11 things that can lead to content being removed, including “spreading false or misleading information.”

The guidelines page has a separate section addressing “content that contradicts widely accepted public health guidelines.” Seven bullet points cover the type of posts that will be taken down. They include content that “promulgates unverified claims about the effectiveness, side effects, or implications of vaccination with FDA-authorized vaccines” and that “promulgates false data about deaths, hospitalizations, infection rates associated with infectious disease.”

Doximity said in an emailed statement that while it supports the exchange of ideas “about emerging science and the latest medical news” among its users, posting medical misinformation is explicitly prohibited.

“Like most virtual communities, we have community guidelines in place to ensure that Doximity remains a safe and respectful environment,” the company said. “We employ a rigorous clinical review process, staffed by physicians, to evaluate member comments that are flagged as being potential misinformation.”

Doctors have a ‘powerful platform in society’

The risk to doctors goes well beyond any potential action taken by Doximity. Last week, the Federation of State Medical Boards, a nonprofit representing medical boards across the country, released a statement telling doctors they can lose their license for such activity.

“Physicians who generate and spread COVID-19 vaccine misinformation or disinformation are risking disciplinary action by state medical boards, including the suspension or revocation of their medical license,” the FSMB said. “Due to their specialized knowledge and training, licensed physicians possess a high degree of public trust and therefore have a powerful platform in society, whether they recognize it or not.”

The FSMB said it was responding to a “dramatic increase” in the dissemination of false information by doctors on social media and elsewhere. But the group isn’t actively scouring sites for abusers.

Joe Knickrehm, a spokesperson for FSMB, told CNBC in an email that state medical boards operate on a “complaint-driven” system, typically taking action when tipped off by patients, health systems, other doctors or members of the public. He said the group runs a free tool called Docinfo.org that allows anyone to look up information on a doctor and to file a complaint.

As a company, Doximity has tried to keep users informed about Covid-19 developments, treatments and vaccines. Early in the pandemic, Doximity launched a private Covid-19 newsroom for clinicians to find updates and recommendations and to discuss best practices. It also offered its new video telehealth service for free, through early 2021, to help doctors work with patients remotely.

Doximity also has a site called Op-Med, where members publish opinion pieces and their personal stories. Numerous doctors have written pieces touting the vaccines with headlines like “How the COVID-19 vaccine has changed my life (so far)” and “How giving vaccinations rekindled my love of practicing medicine.”

But determining where to draw the line between providing an outlet for healthy online debate and letting harmful misinformation proliferate is a problem that’s befuddled social networks for years. It’s particularly important on matters of life and death.

As it is, some anti-vaxxers already think they’re being silenced by Doximity. In one recent comment to a vaccine story, an anesthesiologist said he’d been offered the opportunity to invest in Doximity’s IPO, which included up to 15% allocation to doctors on the platform.

He wrote that Doximity had censored a prior post because it didn’t fit within the company’s “position on vaccination.” Thus, he had no interest in IPO shares.

“I will not invest in your directed information highway with your thought control bulls---,” he wrote in the comment. “Have a good day.”

https://www.cnbc.com/2021/08/06/doximity-social-network-for-doctors-full-of-antivax-disinformation.html

Fauci: Expect 'a flood' of COVID-19 vaccine mandates after full FDA approval

 As soon as the Food and Drug Administration issues a full approval for a COVID-19 vaccine, there will be "a flood" of vaccine mandates at businesses and schools across the nation, Dr. Anthony Fauci told USA TODAY's editorial board on Friday.

Mandates aren't going to happen at the federal level, but vaccine approval will embolden many groups, he predicted. 

"Organizations, enterprises, universities, colleges that have been reluctant to mandate at the local level will feel much more confident," he said.

"They can say, 'If you want to come to this college or this university, you've got to get vaccinated. If you want to work in this plant, you have to get vaccinated. If you want to work in this enterprise, you've got to get vaccinated. If you want to work in this hospital, you've got to get vaccinated.'"

Fauci doesn't see more lockdowns in the nation's future. They were issued early in the pandemic to keep hospitals from being overwhelmed, known as "flattening the curve."

"The rationale for shutting down was that the hospital system would not be able to handle the surge of cases because everybody was getting sick," he said.

With upwards of 70% of adults having had at least one dose of vaccine, the epidemic has shifted to one of the unvaccinated, he said. 

"When you walk into a hospital, what you're going to see is a lot of young people, some of whom are seriously ill, but you're not seeing an overwhelming outstripping of the capability of the hospitals throughout the country," he said.

Lies, mistruths and death

While he's attacked online and in conservative media every day, Fauci said he worries less about himself than for the nation as a whole.

"This is a dystopian world we're living in," he said. The public is awash in lies and misinformation about COVID-19 and the vaccines, "they are being misled."

The Backstory:My brother is one of millions who won't get the COVID-19 vaccine. I asked why. Here are his reasons, my responses.

With COVID-19 cases rising among the unvaccinated as the highly contagious delta variant spreads, Fauci hopes people's "better angels" will prevail over the sea of lies on social media. 

Americans, he hopes, will say, "I'm not going to take any of this. I'm seeing everybody around me get sick and dying. Let me just go ahead and get vaccinated.'"

Protecting children

The delta variant has thrown the danger of COVID-19 to young children into sharp relief. In Tennessee, the Department of Health projects the state's children's hospitals are on pace to be completely full by the end of next week. 

The state's health commissioner, Dr. Lisa Piercey, said the delta variant is rapidly spreading among children, who are quickly showing symptoms after possible exposure, possibly amounting to a much faster incubation time than previous versions of the virus.

Children under 12 are not yet eligible for the vaccine, so the adults around them must be their protection, Fauci said. 

At schools, everyone needs to be vaccinated, he said, teachers, assistants, janitors, "anybody who is anywhere near a child in what should be a protected environment of a school."

Because in the current political environment that won't happen, Fauci said masks are the next best thing. Schools are crucial for children's mental health and intellectual, physical and social development, so it's important they stay open. 

"I would rather have a child be a little bit uncomfortable with a mask on and be healthy than a comfortable child without a mask in an ICU," he said. "It just doesn't make any sense to me why you would want to not protect the children."

A 'smoldering' future for US

The epidemic in the United States could be endedonce and for all if everyone would get vaccinated, Fauci said. Barring that, he worries we're in it for the long term.

"You will get a smoldering level of infection that will just go right into the fall, get confused with influenza in the winter and then come back again in the spring," he said.

The unvaccinated will continue to get sick and some will die. The young and healthy are statistically not likely to become seriously ill if infected, but they don't live in a vacuum, he said. The more people who are infected, the more chance the virus has to mutate into an even more dangerous variant. 

When will everyone be vaccinated for COVID-19? Here's how the vaccine rollout is going

"All of the sudden, your decision not to get vaccinated goes beyond your own vacuum and influences society," he said. 

That holds true for the world as well – unless the virus is stopped everywhere, it will continue to mutate and could come back in a form that can evade current vaccines.  

That's different from many vaccine-preventable diseases such as measles, which doesn't mutate. And it's why getting vaccines to the rest of the world is critical.

"If we're protected against measles here and there are a million cases of measles in Afghanistan or in India or in Uganda or in Kenya and somebody comes over here, it almost doesn't matter. But if we're protected against one group of (COVID-19) variants and a bizarre variant emerges somewhere in a low- or middle-income country, then we're vulnerable," he said. 

Fauci ended by emphasizing that while the COVID-19 vaccines are not perfect, they do one thing extraordinarily well – keep people who get COVID-19 from becoming severely ill or dying.

"The reason to get vaccinated is not so that you can go around without wearing a mask," he said. The reason is "because we don't want you to wind up in the ICU. And I can guarantee you 99% that if you get vaccinated, you are not going to wind up in the ICU."

https://www.usatoday.com/story/news/health/2021/08/06/anthony-fauci-covid-vaccine-mandates-fda-full-approval/5513121001/

Covid R rate now as low as 0.8 as cases drop in 87% of England

 

England’s R rate has fallen significantly to 0.8 to 1.1, as data shows cases are falling across 87% of the country.

The current R number means that every 10 people infected with Covid will go on to infect 8 to 11 others.

Any rate above 1 means the outbreak is growing in the country and anything below 1 means the virus is in decline.

Last week the number was 1.1 to 1.4, indicating a substantial drop in the rate of infection, according to the UK health security agency.

The estimated daily growth rate range is now -3% to +1%, compared to estimated growth of between +2% to +5% each day reported last week.

Figures for the seven days to August 1 show that out of 315 local areas in England, 37 (12%) have seen a week-on-week rise in rates, 275 (87%) have seen a fall and three are unchanged.

Five areas with the biggest week-on-week rises (cases per 100,000)

  • Lincoln (up from 357.5 to 756.3)
  • Exeter (371.4 to 575.3)
  • North Kesteven (233.5 to 437.1)
  • Norwich (313.7 to 429.7)
  • Breckland (147.9 to 252.2)

Lincoln continues to have the highest rate, with 751 new cases in the seven days to August 1 – the equivalent of 756.3 per 100,000 people. This is up from 357.5 in the seven days to July 25.

Exeter has the second highest rate, up from 371.4 to 575.3, with 756 new cases.
Hull has the third highest rate, up from 490.0 to 543.5, with 1,412 new cases.

Overall infections have fallen in all four home nations except for Northern Ireland, according to official estimates.

Data from the Office for National Statistics (ONS) shows around one in 75 people in English households had Covid-19 in the week to July 31 – down from 65 in the previous week.

That’s the equivalent 722,300 people compared to 856,200 in the previous seven days.

In Scotland, the latest figure was one in 120 (43,000 cases), compared with one in 110 (49,500 cases) the previous week.

One in 230 in Wales (13,000 people) were estimated to have had Covid in the last week of July, compared to one in 160 (18,800 people) in the previous seven days.

Meanwhile in Northern Ireland infections rates have risen from one in 55 people (34,400 cases) to one in 65 (27,200 cases) in a week.

https://metro.co.uk/2021/08/06/covid-r-rate-now-as-low-as-0-8-as-cases-drop-in-87-of-england-15049937/

Amazon to require warehouse workers to wear masks

 Amazon will require all employees at its vast network of warehouses and delivery hubs to begin wearing masks Monday regardless of vaccination status, a significant shift as more U.S. companies reinstate Covid-19 mitigation efforts as cases spike in various parts of the country.

Employees were previously allowed to not wear masks if they had proof of vaccination. Amazon said in an announcement to employees on Friday that extra precautions need to be taken “in response to the rapid spread of the Covid-19 Delta variant in the U.S. and guidance from public health authorities and our own medical experts.” The company added it hopes this new requirement will be temporary and last only a “few weeks.” It confirmed the change in policy to NBC News.

Amazon continued to encourage all its employees to get vaccinated. 

“We believe getting vaccinated is the single most important thing you can do to protect yourself,” the employee announcement read.

Some other companies with large workforces have instituted similar policies in recent days. Walmart shared last week it will begin requiring all employees in stores in high-risk areas to wear masks regardless of vaccination status. For corporate and management-level employees at Walmart, vaccinations will be required to return to the office.

While Amazon has not said whether it will mandate vaccinations for any of its employees, the company did share with its corporate workers that the date for peoples to begin returning to the office was pushed from early September to early January in response to the changing conditions of the pandemic.

https://www.nbcnews.com/tech/tech-news/amazon-require-warehouse-workers-wear-masks-rcna1626

Live Nation Lets Artists Require Vaccination/Proof of Negative Test Result for U.S. Concerts

 As the live-music industry resumes operations while the Covid-19 variant spreads across the globe, Live Nation has issued a “best practices” document to artist teams for its events.

According to the document, which was obtained by Variety, artists performing at its venues can  require proof of vaccination or a negative Covid test for entry, and effective October 4, “all employees in the U.S. [must] be vaccinated to enter one of our events, venues or offices – with limited exceptions as may be required by law.” The document was signed by Live Nation CEO Michael Rapino.

Because Covid protocols vary state by state, practices for live events have varied as well. But as the variant continues to disrupt lives and livelihoods all over the world, Live Nation — the world’s largest live entertainment company — evidently has seen fit to put standard practices into place.

https://variety.com/2021/music/news/live-nation-vaccination-best-practices-concerts-1235036359/

This Year's Top 10 Medical Schools from U.S. News & World Report

 For prospective medical school students looking for the cream of the crop, each year in March, U.S. News & World Report ranks the best schools in research and primary care.

Harvard, New York University, and Duke took the top three spots, respectively, on the "2022 Best Medical Schools for Research" list. The institutions that ranked high on the list received top marks for funding, cutting-edge technology, and research completed by students and faculty, according to U.S. News.

As for the best medical schools for primary care, the University of Washington in Seattle, University of California San Francisco, and University of North Carolina at Chapel Hill topped the list. These schools and others that earned top billing excel in preventive medicine and public health training for students interested in becoming primary care physicians or family doctors, U.S. News said.

U.S. News evaluated medical schools for research and primary care on faculty resources and academic achievement of entering students, as well as qualitative assessments by schools and residency directors. Some of the indicators it looked at included peer assessment scores from school deans, student selectivity, ratio of faculty to students, federal research activity per faculty member, and graduates practicing in primary care.

Below are the lists of the top 10 medical schools for research and primary care.

2022 Best Medical Schools: Research

1. Harvard University, Boston

  • Overall score: 100/100
  • 2020 median undergrad grade point average (GPA): 3.9
  • 2020 median total MCAT score: 520
  • 2020 acceptance rate: 3.5%
  • 2020 out-of-state tuition and fees: $66,787
  • 2020 total enrollment: 700

2. New York University, New York City (Grossman)
  • Overall score: 84/100
  • 2020 median undergrad GPA: 4.0
  • 2020 median total MCAT score: 522
  • 2020 acceptance rate: 2.2%
  • 2020 out-of-state tuition and fees: $3,480
  • 2020 total enrollment: 417

3. Duke University, Durham, North Carolina

  • Overall score: 75/100
  • 2020 median undergrad GPA: 3.9
  • 2020 median total MCAT score: 519
  • 2020 acceptance rate: 3.6%
  • 2020 out-of-state tuition and fees: $64,911
  • 2020 total enrollment: 502

4. Columbia University, New York City (tie)

  • Overall score: 74/100
  • 2020 median undergrad GPA: 3.9
  • 2020 median total MCAT score: 521
  • 2020 acceptance rate: 4.1%
  • 2020 out-of-state tuition and fees: $71,107
  • 2020 total enrollment: 585

5. Stanford University, California (tie)

  • Overall score: 74/100
  • 2020 median undergrad GPA: 3.8
  • 2020 median total MCAT score: 518
  • 2020 acceptance rate: 2.3%
  • 2020 out-of-state tuition and fees: $63,311
  • 2020 total enrollment: 484

6. University of California San Francisco (tie)

  • Overall score: 74/100
  • 2020 median undergrad GPA: 3.9
  • 2020 median total MCAT score: 517
  • 2020 acceptance rate: 3.9%
  • 2020 out-of-state tuition and fees: $55,036
  • 2020 total enrollment: 664

7. Johns Hopkins University, Baltimore (tie)

  • Overall score: 72/100
  • 2020 median undergrad GPA: 4.0
  • 2020 median total MCAT score: 521
  • 2020 acceptance rate: 6.8%
  • 2020 out-of-state tuition and fees: $62,397
  • 2020 total enrollment: 477

8. University of Washington, Seattle (tie)

  • Overall score: 72/100
  • 2020 median undergrad GPA: 3.7
  • 2020 median total MCAT score: 511
  • 2020 acceptance rate: 4.7%
  • 2020 out-of-state tuition and fees: $69,569
  • 2020 total enrollment: 1,123

9. University of Pennsylvania, Philadelphia (Perelman)

  • Overall score: 71/100
  • 2020 median undergrad GPA: 3.9
  • 2020 median total MCAT score: 522
  • 2020 acceptance rate: 5.2%
  • 2020 out-of-state tuition and fees: $65,497
  • 2020 total enrollment: 616

10. Yale University, New Haven, Connecticut

  • Overall score: 67/100
  • 2020 median undergrad GPA: 3.9
  • 2020 median total MCAT score: 519
  • 2020 acceptance rate: 6.2%
  • 2020 out-of-state tuition and fees: $65,954
  • 2020 total enrollment: 394

2022 Best Medical Schools: Primary Care

1. University of Washington, Seattle

  • Overall score: 100/100
  • 2020 median undergrad GPA: 3.7
  • 2020 median total MCAT score: 511
  • 2020 acceptance rate: 4.7%
  • 2020 out-of-state tuition and fees: $69,569
  • 2020 total enrollment: 1,123

2. University of California San Francisco

  • Overall score: 88/100
  • 2020 median undergrad GPA: 3.9
  • 2020 median total MCAT score: 517
  • 2020 acceptance rate: 3.9%
  • 2020 out-of-state tuition and fees: $55,036
  • 2020 total enrollment: 664

3. University of North Carolina at Chapel Hill

  • Overall score: 85/100
  • 2020 median undergrad GPA: 3.8
  • 2020 median total MCAT score: 512
  • 2020 acceptance rate: 4.1%
  • 2020 out-of-state tuition and fees: $62,095
  • 2020 total enrollment: 782

4. Oregon Health and Science University, Portland

  • Overall score: 83/100
  • 2020 median undergrad GPA: 3.8
  • 2020 median total MCAT score: 511
  • 2020 acceptance rate: 3.7%
  • 2020 out-of-state tuition and fees: $76,393
  • 2020 total enrollment: 617

5. University of Minnesota, Minneapolis

  • Overall score: 79/100
  • 2020 median undergrad GPA: 3.8
  • 2020 median total MCAT score: 511
  • 2020 acceptance rate: 5.6%
  • 2020 out-of-state tuition and fees: $59,569
  • 2020 total enrollment: 1,051

6. University of Colorado, Aurora (tie)
  • Overall score: 77/100
  • 2020 median undergrad GPA: 3.8
  • 2020 median total MCAT score: 513
  • 2020 acceptance rate: 3.1%
  • 2020 out-of-state tuition and fees: $67,474
  • 2020 total enrollment: 719

7. University of Nebraska Medical Center, Omaha (tie)

  • Overall score: 77/100
  • 2020 median undergrad GPA: 3.8
  • 2020 median total MCAT score: 512
  • 2020 acceptance rate: 10.6%
  • 2020 out-of-state tuition and fees: $62,675
  • 2020 total enrollment: 513

8. Harvard University, Boston

  • Overall score: 70/100
  • 2020 median undergrad GPA: 3.9
  • 2020 median total MCAT score: 520
  • 2020 acceptance rate: 3.5%
  • 2020 out-of-state tuition and fees: $66,787
  • 2020 total enrollment: 700

9. University of Kansas Medical Center, Kansas City

  • Overall score: 69/100
  • 2020 median undergrad GPA: 3.9
  • 2020 median total MCAT score: 511
  • 2020 acceptance rate: 8.6%
  • 2020 out-of-state tuition and fees: $67,930
  • 2020 total enrollment: 854

10. University of Massachusetts, Worcester

  • Overall score: 67/100
  • 2020 median undergrad GPA: 3.8
  • 2020 median total MCAT score: 514
  • 2020 acceptance rate: 8.7%
  • 2020 out-of-state tuition and fees: $64,980
  • 2020 total enrollment: 670

One Vax Dose and Done? Evidence Mounts in Previously Infected

 People with previous COVID-19 infection had higher antibody levels after one dose of Pfizer vaccine compared with uninfected people after two doses, a small lab study of 59 people showed.

Not only that, but IgG levels did not increase after the second dose among those previously infected, which could indicate that one dose of vaccine may be sufficient for this population, reported James Moy, MD, of Rush University Medical Center in Chicago, and colleagues.

"This study highlights the potential for recommending a single dose for previously infected individuals and may be useful for discussions surrounding vaccination strategy," the authors wrote in a JAMA Network Open research letter.

Offering one dose of vaccine instead of two to those previously infected with COVID-19 is hotly contested, with some experts conceding it's likely that previously infected individuals only need one dose, but that it would be challenging from a programmatic standpoint.

Indeed, Moy's group urged performing "baseline serological testing" for previously infected individuals, but CDC and the agency's Advisory Committee on Immunization Practices (ACIP) argued that this would be next to impossible to do for the entire country.

At a meeting back in March, ACIP Chair José Romero, MD, who is also director of the Arkansas Department of Health, was concerned that the one-dose strategy would only work if individuals had adequate or high antibody titers. However, if people had no antibodies or low antibodies, they may not have "enough memory B-cells to boost to levels that will be protective," he said.

Moy and colleagues recruited adult participants at the team's academic medical center, and divided them based on infection status. Prior infection was determined by a positive RT-PCR test and/or a positive SARS-CoV-2 antibody result. Overall, 30 participants had no evidence of infection, while 29 did.

The authors measured SARS-CoV-2 spike IgG levels at baseline and then following one and two doses of the Pfizer vaccine among all participants.

The 59 participants had a mean age of 42, almost three-quarters were women, and 49% were white. Mean IgG differences between the first and second dose were non-significant in previously infected individuals. Interestingly, four participants reported a previous positive COVID-19 test via RT-PCR, but had no evidence of antibodies.

"Vaccine responses in these four participants resembled infection-naive individuals," Moy's group noted, adding that because this group did not develop S-protein antibodies, baseline testing should be required before forgoing a second dose.

Limitations to the data, the researchers said, included the small sample size and lack of diversity of participants, as well as lack of neutralization studies and T-cell response studies.


Disclosures

This study was supported by Abbott Diagnostics Division Research and Development Funding.

Moy disclosed no conflicts of interest; three co-authors were employed at Abbott Laboratories.