An anonymous reader quotes a report from Scientific American: For years scientists have sought to create the ultimate cancer-screening test -- one that can reliably detect a malignancy early, before tumor cells spread and when treatments are more effective. A new method reported today in Nature Communications brings researchers a step closer to that goal. By using a blood test, the international team was able to diagnose cancer long before symptoms appeared in nearly all the people it tested who went on to develop cancer. [...] Kun Zhang, a bioengineer at the University of California, San Diego, and a co-author of the study, and his colleagues began collecting samples from people before they had any signs that they had cancer. In 2007 the researchers began recruiting more than 123,000 healthy individuals in Taizhou, China, to undergo annual health checks -- an effort that required building a specialized warehouse to store the more than 1.6 million samples they eventually accrued. Around 1,000 participants developed cancer over the next 10 years.

Zhang and his colleagues focused on developing a test for five of the most common types of cancer: stomach, esophageal, colorectal, lung and liver malignancies. The test they developed, called PanSeer, detects methylation patterns in which a chemical group is added to DNA to alter genetic activity. Past studies have shown that abnormal methylation can signal various types of cancer, including pancreatic and colon cancer. The PanSeer test works by isolating DNA from a blood sample and measuring DNA methylation at 500 locations previously identified as having the greatest chance of signaling the presence of cancer. A machine-learning algorithm compiles the findings into a single score that indicates a person's likelihood of having the disease. The researchers tested blood samples from 191 participants who eventually developed cancer, paired with the same number of matching healthy individuals. They were able to detect cancer up to four years before symptoms appeared with roughly 90 percent accuracy and a 5 percent false-positive rate.

An anonymous reader quotes a report from Bloomberg: Scores of Russia's business and political elite have been given early access to an experimental vaccine against Covid-19, according to people familiar with the effort, as the country races to be among the first to develop an inoculation. Top executives at companies including aluminum giant United Co. Rusal, as well as billionaire tycoons and government officials began getting shots developed by the state-run Gamaleya Institute in Moscow as early as April, the people said. They declined to be identified as the information isn't public.

Kremlin spokesman Dmitry Peskov, who recovered from Covid-19 after being hospitalized with the virus in May, said he doesn't know the names of anyone who's received the institute's vaccine. Peskov's comments followed a Health Ministry statement that said only participants in Gamaleya's trials are currently eligible for the jabs. While the new shots are "safe" because they're based on proven vaccines for other diseases, their effectiveness has yet to be determined, according to Sergei Netesov, a former executive at Vector, a state-run virology center in Novosibirsk, Siberia, that's also working on an inoculation. "Those who take it do so at their own risk," Netesov said.

"The risk of nasty side effects in the Moderna and Oxford trials should be made clear now, before it ends up as fodder for the skeptics," argues Hilda Bastian, a former consumer health care advocate and a Ph.D. student at Bond University who studies evidence-based medicine. An anonymous reader shares an excerpt from her article via Wired: On Monday, vaccine researchers from Oxford University and the pharmaceutical company AstraZeneca announced results from a "Phase 1/2 trial," suggesting their product might be able to generate immunity without causing serious harm. Similar, but smaller-scale results, were posted just last week for another candidate vaccine produced by the biotech firm Moderna, in collaboration with the U.S. National Institutes of Health. [...] Back in May, a CNN report described the Oxford group as being "the most aggressive in painting the rosiest picture" of its product, so let's start with them. Just how rosy is the Oxford picture really? It's certainly true that this week's news shows the vaccine has the potential to provide protection from Covid-19. But there are flies in the ointment. After the first clinical trial for this vaccine began in April, for example, the researchers added new study arms in which people got acetaminophen every six hours for 24 hours after the injection. That's not featured in their marketing, of course, and I saw no discussion of this unusual step in media coverage in early summer. Newspapers only said the vaccine had been proven "safe with rhesus monkeys," and did not cause any adverse effects in those animal tests. It was a worrying signal though: How rough a ride were people having with this vaccine? Was the acetaminophen meant to keep down fever, headaches, malaise -- or all of the above?

The press release for Monday's publication of results from the Oxford vaccine trials described an increased frequency of "minor side effects" among participants. A look at the actual paper, though, reveals this to be a marketing spin that has since been parroted in media reports. Yes, mild reactions were far more common than worse ones. But moderate or severe harms -- defined as being bad enough to interfere with daily life or needing medical care -- were common, too. Around one-third of people vaccinated with the Covid-19 vaccine without acetaminophen experienced moderate or severe chills, fatigue, headache, malaise, and/or feverishness. Close to 10 percent had a fever of at least 100.4 degrees and just over one-fourth developed moderate or severe muscle aches. That's a lot, in a young and healthy group of people -- and the acetaminophen didn't help much for most of those problems. The paper's authors designated the vaccine as "acceptable" and "tolerated," but we don't yet know how acceptable this will be to most people.

There is another red flag. Clinical trials for other Covid-19 vaccines have placebo groups, where participants receive saline injections. Only one of the Oxford vaccine trials is taking this approach, however; the others instead compare the experimental treatment to an injected meningococcal vaccine. There can be good reasons to do this: Non-placebo injections may mimic telltale signs that you've received an active vaccine, such as a skin reaction, making the trial more truly "blind." But their use also opens the door to doubt-sowing claims that any harms of the new vaccine are getting buried among the harms already caused by the control-group, "old" vaccines.What about the Moderna vaccine? "According to the press release from May, there were no serious adverse events for the people in that particular dosage group," reports Wired. "But last week's paper shows the full results: By the time they'd had two doses, every single one was showing signs of headaches, chills or fatigue; and for at least 80 percent this could have been enough to interfere with their normal activities. A participant who had a severe reaction to a particularly high dose has talked in detail about how bad it was: If reactions even half as bad as this were to be common for some of these vaccines, they will be hard sells once they reach the community -- and there could be a lot of people who are reluctant to get the second injection."

UPDATE 7/27/20: Slashdot interviewed Oxford Vaccine Trial participant Jennifer Riggins and asked what her reaction was to Wired's article. Riggins is an American technology journalist and marketer who's self-employed in London. Here's what she said:

"I think the article is a poorly written, poorly researched opinion piece. It says offering acetaminophen or paracetamol is unusual with vaccines. I'm a working mom with a three-year-old, and you are told to give them acetaminophen or paracetamol before all live vaccines as they can cause discomfort and fever for the first 24 to 48 hours.

"I'm actually surprised this article was in Wired that tends to be reputable. It seems to be written by a vaccine skeptic at best who knows little about them. This is a dangerous message because we most likely won't have a widely distributed vaccine til 2021 at earliest. Even longer if you consider, like the chicken pox vaccine, it needs a booster for efficacy. This flu season is going to be awful and then combined with this coronavirus. Add to that less kids are getting vaccinated or at least are delayed during the pandemic. Any antivaxxer message is incredibly dangerous. We won't be able to have herd immunity for Covid-19 by winter but we could for the flu which will save so many lives."

Discover magazine reports: For years, many artificial intelligence enthusiasts and researchers have promised that machine learning will change modern medicine. Thousands of algorithms have been developed to diagnose conditions like cancer, heart disease and psychiatric disorders. Now, algorithms are being trained to detect COVID-19 by recognizing patterns in CT scans and X-ray images of the lungs.

Many of these models aim to predict which patients will have the most severe outcomes and who will need a ventilator. The excitement is palpable; if these models are accurate, they could offer doctors a huge leg up in testing and treating patients with the coronavirus. But the allure of AI-aided medicine for the treatment of real COVID-19 patients appears far off. A group of statisticians around the world are concerned about the quality of the vast majority of machine learning models and the harm they may cause if hospitals adopt them any time soon.

So far, their reviews of COVID-19 machine learning models aren't good: They suffer from a serious lack of data and necessary expertise from a wide array of research fields. But the issues facing new COVID-19 algorithms aren't new at all: AI models in medical research have been deeply flawed for years...
"The main problems appear to be (perhaps unsurprisingly) a lack of necessary data, and not enough domain expertise," writes Slashdot reader shirappu: The leader of the above group of statisticians, Maarten van Smeden, pointed to a lack of collaboration between researchers as a road block in the way of developing truly accurate models. "You need expertise not only of the modeler," he said, "but you need statisticians, epidemiologists and clinicians to work together to make something that is actually useful."
One biostatistician has even been arguing that with many current AI models, medical researchers are using machine learning to "torture their data until it spits out a confession."

CNN shares some bad news. "After people are infected with the novel coronavirus, their natural immunity to the virus could decline within months, a new pre-print paper suggests." The paper was co-authored by 37 researchers from seven different institutions: The paper, released on the medical server medrxiv.org on Saturday and not yet published in a peer-reviewed medical journal, suggests that antibody responses may start to decline 20 to 30 days after Covid-19 symptoms emerge. Antibodies are the proteins the body makes to fight infection...

Since early on in the pandemic, the World Health Organization has warned that people who have had Covid-19 are not necessarily immune from getting the virus again. Yet the new study had some limitations, including that more research is needed to determine whether similar results would emerge among a larger group of patients and what data could show over longer periods of time when it comes to infection with the coronavirus...
"The report is the latest in a growing chain of evidence that immunity to COVID-19 is short-lived," reports the San Francisco Chronicle: A Chinese study published June 18 in the journal Nature Medicine also showed coronavirus antibodies taking a nosedive. The study of 74 patients, conducted by Chongqing Medical University, a branch of the Chinese Center for Disease Control and Prevention, showed that more than 90% exhibited sharp declines in the number of antibodies within two to three months after infection... Studies of four seasonal coronaviruses that cause colds show that although people develop antibodies, the immune response declines over time and people become susceptible again. Scientists suspect that the severity of cold symptoms is reduced by previous infections.
The Chronicle reports this new information suggests two implications:

• "Waning antibodies affect vaccine development," said Shannon Bennett, the chief of science at San Francisco's California Academy of Sciences. "Where natural immunity doesn't really develop or last, then vaccine programs are not likely to be easily successful or achievable..."

• The Chronicle adds, "Whatever happens, epidemiologists hope the recent reports about antibody viability put to rest the concept embraced by many young people of herd immunity, where the disease can't find any more victims because so many people have survived infections and must be immune. 'This attitude that if I go out there and just get exposed — get it over with — then I'll be immune is a dangerous presumption,' Bennett said. Now more than ever."

Face masks "offer much more protection against coronavirus than many think," reports the Los Angeles Times. [Alternate version here ....] There's a common refrain that masks don't protect you; they protect other people from your own germs, which is especially important to keep unknowingly infected people from spreading the coronavirus. But now, there's mounting evidence that masks also protect you.

If you're unlucky enough to encounter an infectious person, wearing any kind of face covering will reduce the amount of virus that your body will take in. As it turns out, that's pretty important. Breathing in a small amount of virus may lead to no disease or far more mild infection. But inhaling a huge volume of virus particles can result in serious disease or death. That's the argument Dr. Monica Gandhi, UC San Francisco professor of medicine and medical director of the HIV Clinic at Zuckerberg San Francisco General Hospital, is making about why — if you do become infected with the virus — masking can still protect you from more severe disease...

She cited an outbreak at a seafood plant in Oregon where employees were given masks, and 95% of those who were infected were asymptomatic.... The protective effects are also seen in countries where masks are universally accepted for years, such as Taiwan, Thailand, South Korea and Singapore. "They have all seen cases as they opened ... but not deaths," Gandhi said.
"The emerging scientific data is clear: wearing a mask doesn't only protect others, it also significantly reduces your own risk of getting Coronavirus," one U.S. governor recently pointed out.

"So if you're a selfish bastard and wearing a mask to protect others isn't enough of a reason to do so, then maybe protecting yourself is?"

The World Health Organization (WHO) should soon get results from clinical trials it is conducting of drugs that might be effective in treating COVID-19 patients, its Director General Tedros Adhanom Ghebreyesus said on Friday. From a report: "Nearly 5,500 patients in 39 countries have so far been recruited into the Solidarity trial," he told a news briefing, referring to clinical studies the U.N. agency is conducting. "We expect interim results within the next two weeks." The Solidarity Trial started out in five parts looking at possible treatment approaches to COVID-19: standard care; remdesivir; the anti-malaria drug touted by U.S. President Donald Trump, hydroxychloroquine; the HIV drugs lopinavir/ritonavir; and lopanivir/ritonavir combined with interferon. Earlier this month, it stopped the arm testing hydroxychloroquine, after studies indicated it showed no benefit in those who have the disease, but more work is still needed to see whether it may be effective as a preventative medicine. Mike Ryan, head of the WHO's emergencies programme, said it would be unwise to predict when a vaccine could be ready against COVID-19, the respiratory disease caused by the novel coronavirus that has killed more than half a million people. Earlier this week, the WHO also warned the some countries may have to reinstate lockdowns as coronavirus pandemic accelerates.

"What if a single injection could lower blood levels of cholesterol and triglycerides — for a lifetime?" asks the New York Times.

"In the first gene-editing experiment of its kind, scientists have disabled two genes in monkeys that raise the risk for heart disease." (Alternate source here.) Humans carry the genes as well, and the experiment has raised hopes that a leading killer may one day be tamed. "This could be the cure for heart disease," said Dr. Michael Davidson, director of the Lipid Clinic at the University of Chicago Pritzker School of Medicine, who was not involved in the research.

But it will be years before human trials can begin, and gene-editing technology so far has a mixed tracked record. It is much too early to know whether the strategy will be safe and effective in humans; even the monkeys must be monitored for side effects or other treatment failures for some time to come. The results were presented on Saturday at the annual meeting of the International Society for Stem Cell Research, this year held virtually with about 3,700 attendees around the world. The scientists are writing up their findings, which have not yet been peer-reviewed or published...

Both genes are active in the liver, which is where cholesterol and triglycerides are produced. People who inherit mutations that destroyed the genes' function do not get heart disease.

Nearly 25 million Americans may have contracted the coronavirus, a figure 10 times higher than the number of confirmed cases, the Centers for Disease Control and Prevention (CDC) said Thursday. The Hill reports: In a briefing with reporters Thursday, CDC Director Robert Redfield said surveys of blood samples taken from around the country suggest that millions of Americans may have contracted the virus either without knowing it or with only minimal symptoms. For every one confirmed case, Redfield said, the CDC estimates that 10 more people have been infected. "This virus causes so much asymptomatic infection," Redfield said. "We probably recognized about 10 percent of the outbreak."

Almost 2.4 million Americans have tested positive for the coronavirus, according to the Center for Systems Science and Engineering at the Johns Hopkins University of Medicine. Redfield said the serological surveys of blood samples, collected both for coronavirus tests and for other reasons like blood donations or laboratory tests, showed that between 5 percent and 8 percent of Americans have contracted the virus. Most people who contract the SARS-CoV-2 virus show few if any symptoms, and only a small percentage require hospitalization. But while the number of potentially infected people is multitudes higher than the number of confirmed cases, Redfield also said the relatively low percentage of Americans who have been infected means hundreds of millions more remain at risk.

One study promised that popular blood-pressure drugs were safe for people infected with the coronavirus. Another paper warned that anti-malaria drugs endorsed by President Trump actually were dangerous to these patients. The studies, published in the New England Journal of Medicine and The Lancet, were retracted shortly after publication, following an outcry from researchers who saw obvious flaws. From a report: The hasty retractions, on the same day this month, have alarmed scientists worldwide who fear that the rush for research on the coronavirus has overwhelmed the peer review process and opened the door to fraud, threatening the credibility of respected medical journals just when they are needed most. Peer review is supposed to safeguard the quality of scientific research. When a journal receives a manuscript, the editors ask three or more experts in the field for comments. The reviewers' written assessments may force revisions in a paper or prompt the journal to reject the work altogether. The system, widely adopted by medical journals in the middle of the 20th century, undergirds scientific discourse around the world. "The problem with trust is that it's too easy to lose and too hard to get back," said Dr. Jerome Kassirer, a former editor in chief of the New England Journal of Medicine, which published one of the retracted papers in early May. "These are big blunders." If outside scientists detected problems that weren't identified by the peer reviewers, then the journals failed, he said. Like hundreds of other researchers, Dr. Kassirer called on the editors to publish full explanations of what happened.

An anonymous reader quotes Reuters: British scientists halted a major drug trial on Friday after it found that the anti-malarial hydroxychloroquine, touted by U.S. President Donald Trump as a potential "game changer" in the pandemic, was "useless" at treating COVID-19 patients. "This is not a treatment for COVID-19. It doesn't work," Martin Landray, an Oxford University professor who is co-leading the RECOVERY trial, told reporters.

"This result should change medical practice worldwide. We can now stop using a drug that is useless..."

Landray, a professor of medicine and epidemiology at Oxford University, noted the "huge speculation" about the drug as a treatment for COVID-19 but said there had been until now "an absence of reliable information from large randomised trials". He said the preliminary results from RECOVERY, which was a randomised trial, were now quite clear: hydroxychloroquine does not reduce the risk of death among hospitalised patients with COVID-19.

"If you're admitted to hospital, don't take hydroxychloroquine," he said.
The trial involved over 11,000 patients in a randomized trial begun in March.

The article ends by quoting Parastou Donyai, director of Pharmacy Practice at the University of Reading in England, who describes the announcement as "welcome relief to thousands of scientists, doctors and academics who have been crying out for proper proof of whether hydroxychloroquine works in COVID-19 or not" -- and calling the conclusion that it does not work "definitive."

The malaria drug hydroxychloroquine did not help prevent people who had been exposed to others with Covid-19 from developing the disease, according to the results of an eagerly awaited study that was published Wednesday in the New England Journal of Medicine. From a report: Despite a lack of evidence, many people began taking the medicine to try to prevent infection early in the Covid-19 pandemic, following anecdotal reports it could be effective and claims by President Trump and conservative commentators. Trump, too, said he took hydroxychloroquine to prevent infection. But the new study, the first double-blind randomized, placebo-controlled trial of hydroxychloroquine, found otherwise. "I think in the setting of post-exposure prophylaxis, it doesn't seem to work," said Sarah Lofgren, an assistant professor at the University of Minnesota who is a co-author of the study. Other studies of hydroxychloroquine are ongoing. Also Wednesday, the World Health Organization said it is resuming a clinical trial testing hydroxychloroquine as a treatment after pausing it over safety concerns.

AmiMoJo shares a report from The Guardian The World Health Organization and a number of national governments have changed their Covid-19 policies and treatments on the basis of flawed data from a little-known U.S. healthcare analytics company, also calling into question the integrity of key studies published in some of the world's most prestigious medical journals. Surgisphere, whose employees appear to include a sci-fi writer and adult content model, provided the database behind Lancet and New England Journal of Medicine hydroxychloroquine studies. Data it claims to have legitimately obtained from more than a thousand hospitals worldwide formed the basis of scientific articles that have led to changes in Covid-19 treatment policies in Latin American counties. It was also behind a decision by the WHO and research institutes around the world to halt trials of the controversial drug hydroxychloroquine. Late on Tuesday, the Lancet released an "expression of concern" about its published study. The New England Journal of Medicine has also issued a similar notice. According to an independent audit by authors not affiliated with Surgisphere, the article includes a list of "concerns that have been raised about the reliability of the database." Some of the main points include: Surgisphere's employees have little or no data or scientific background; While Surgisphere claims to run one of the largest and fastest growing hospital databases in the world, it has almost no online presence; and The firm's chief executive, Sapan Desai, has been named in three medical malpractice suits.

Jon Hamilton, reporting for NPR: Mounting evidence suggests the coronavirus is more common and less deadly than it first appeared. The evidence comes from tests that detect antibodies to the coronavirus in a person's blood rather than the virus itself. The tests are finding large numbers of people in the U.S. who were infected but never became seriously ill. And when these mild infections are included in coronavirus statistics, the virus appears less dangerous. "The current best estimates for the infection fatality risk are between 0.5% and 1%," says Caitlin Rivers, an epidemiologist at the Johns Hopkins Center for Health Security.

That's in contrast with death rates of 5% or more based on calculations that included only people who got sick enough to be diagnosed with tests that detect the presence of virus in a person's body. And the revised estimates support an early prediction by Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases and a leading member of the White House coronavirus task force. In an editorial published in late March in The New England Journal of Medicine, Fauci and colleagues wrote that the case fatality rate for COVID-19 "may be considerably less than 1%." But even a virus with a fatality rate less than 1% presents a formidable threat, Rivers says. "That is many times more deadly than seasonal influenza," she says. The new evidence is coming from places such as Indiana, which completed the first phase of a massive testing effort early in May. Further reading: Antibody Tests and Accuracy Issues Leave Some Americans With More Questions Than Answers.

Peter Piot, 71, one of the giants of Ebola and AIDS research, is still battling a coronavirus infection that hit him "like a bus" in March. From a report:"This is the revenge of the viruses," said Dr. Peter Piot, the director of the London School of Hygiene and Tropical Medicine. "I've made their lives difficult. Now they're trying to get me." Dr. Piot, 71 years old, is a legend in the battles against Ebola and AIDS. But Covid-19 almost killed him. "A week ago, I couldn't have done this interview," he said, speaking recently by Skype from his London dining room, a painting of calla lilies behind him. "I was still short of breath after 10 minutes." Looking back, ruefully, on being brought down by a virus after a life as a virus-hunter, Dr. Piot said he had misjudged his prey and had become the hunted.

"I underestimated this one -- how fast it would spread. My mistake was to think it was like SARS, which was pretty limited in scope. Or that it was like influenza. But it's neither." In 1976, as a graduate student in virology at the Institute of Tropical Medicine in Antwerp, Belgium, Dr. Piot was part of the international team that investigated a mysterious viral hemorrhagic fever in Yambuku, Zaire, now the Democratic Republic of Congo. To avoid stigmatizing the town, team members named the virus "Ebola" after a nearby river. Later, in the 1980s, he was one of the scientists who proved that the wasting disease known as "slim" in Africa was caused by the same virus that was killing young gay men elsewhere. From 1991 to 1994, he was president of the International AIDS Society, and then the first director of U.N.AIDS, the United Nations' anti-H.I.V. program.

New research from Imperial College London suggests the coronavirus "may still be spreading at epidemic rates" in 24 different states in America, reports the Washington Post: Some states have had little viral spread or "crushed the curve" to a great degree and have some wiggle room to reopen their economies without generating a new epidemic-level surge in cases. Others are nowhere near containing the virus. The model, which has not been peer reviewed, shows that in the majority of states, a second wave looms if people abandon efforts to mitigate the viral spread. "There's evidence that the U.S. is not under control, as an entire country," said Samir Bhatt, a senior lecturer in geostatistics at Imperial College....

The Imperial College researchers found in 24 states, the model shows a reproduction number over 1 [suggesting the virus is not waning]. Texas tops the list, followed by Arizona, Illinois, Colorado, Ohio, Minnesota, Indiana, Iowa, Alabama, Wisconsin, Mississippi, Tennessee, Florida, Virginia, New Mexico, Missouri, Delaware, South Carolina, Massachusetts, North Carolina, California, Pennsylvania, Louisiana and Maryland....

This has become a geographically complex pandemic, one that will evolve, especially as people increase their movements in coming weeks. Laws and health regulations vary from state to state, county to county and city to city. There are communities where wearing facial coverings is culturally the norm, while in other places it is rejected on grounds of personal liberty or as refutation of the consensus view of the hazards posed by the virus... Experts in Tennessee are also concerned about people from other states beginning to flock to Nashville and Memphis on summer vacations.

If a surge happens, said David Aronoff, director of the Vanderbilt University infectious disease division, "the tricky part will be putting the toothpaste back in the tube" by shutting down again.
In addition to "behavioural precautions," the researchers recommend rapid testing and contact tracing. But If there's no change in the relationship between mobility and transmission, their report states bluntly that "We predict that deaths over the next two-month period will exceed current cumulative deaths by greater than two-fold...

"We predict that increased mobility following relaxation of social distancing will lead to resurgence of transmission, keeping all else constant."

"The drug US President Donald Trump said he was taking to ward off Covid-19 actually increases the risk of patients with the disease dying from it," reports the BBC, citing a new study published Friday in the Lancet.

"The study said there were no benefits to treating patients with the anti-malarial drug hydroxychloroquine..." Hydroxychloroquine is safe for malaria, and conditions like lupus or arthritis, but no clinical trials have recommended the use of hydroxychloroquine for coronavirus. The Lancet study involved 96,000 coronavirus patients, nearly 15,000 of whom were given hydroxychloroquine — or a related form chloroquine — either alone or with an antibiotic.

The study found that the patients were more likely to die in hospital and develop heart rhythm complications than other Covid patients in a comparison group. The death rates of the treated groups were: hydroxychloroquine 18%; chloroquine 16.4%; control group 9%. Those treated with hydroxychloroquine or chloroquine in combination with antibiotics had an even higher death rate.

The researchers warned that hydroxychloroquine should not be used outside of clinical trials.
The BBC also reports that a separate trial involving over 40,000 healthcare workers around the world is now testing whether hydroxychloroquine could prevent infection.

UPDATE (6/4/2020): The study's three authors retracted their study on June 4th, "because independent peer reviewers could not access the data used for the analysis," reports The Hill. "The source of the data was Surgisphere Corporation, which told peer reviewers it would not transfer the full dataset used for the study because it would violate client agreements and confidentiality requirements."

However, the same day the New England Journal of Medicine published results from a new double-blind randomized, placebo-controlled trial which found hydroxychloroquine didn't help prevent people exposed to others with Covid-19 from developing the disease. One of the study's co-authors said that as a preventative agent, "It doesn't seem to work."

A research team from Duke University has found a small area of the brain in mice that can profoundly shut down pain. "It's located in an area where few people would have thought to look for an anti-pain center, the amygdala, which is often considered the home of negative emotions and responses, like the fight or flight response and general anxiety," reports ScienceDaily. From the report: The researchers found that general anesthesia also activates a specific subset of inhibitory neurons in the central amygdala, which they have called the CeAga neurons (CeA stands for central amygdala; ga indicates activation by general anesthesia). Mice have a relatively larger central amygdala than humans, but [senior author Fan Wang, the Morris N. Broad Distinguished Professor of neurobiology in the School of Medicine] said she had no reason to think we have a different system for controlling pain. Using technologies that Wang's lab has pioneered to track the paths of activated neurons in mice, the team found the CeAga was connected to many different areas of the brain, "which was a surprise," Wang said.

By giving mice a mild pain stimulus, the researchers could map all of the pain-activated brain regions. They discovered that at least 16 brain centers known to process the sensory or emotional aspects of pain were receiving inhibitory input from the CeAga. Using a technology called optogenetics, which uses light to activate a small population of cells in the brain, the researchers found they could turn off the self-caring behaviors a mouse exhibits when it feels uncomfortable by activating the CeAga neurons. Paw-licking or face-wiping behaviors were "completely abolished" the moment the light was switched on to activate the anti-pain center.

When the scientists dampened the activity of these CeAga neurons, the mice responded as if a temporary insult had become intense or painful again. They also found that low-dose ketamine, an anesthetic drug that allows sensation but blocks pain, activated the CeAga center and wouldn't work without it. Now the researchers are going to look for drugs that can activate only these cells to suppress pain as potential future pain killers, Wang said. The study has been published in the journal Nature Neuroscience.

An anonymous reader quotes a report from The Wall Street Journal: Bob Wachter, the chairman of the department of medicine at the University of California, San Francisco, has had a front-row seat to the coronavirus pandemic. Dr. Wachter's job, at least in part, is to keep the department's 3,000 or so faculty, trainees and staff current on developments in research, education and clinical care. But most days he sets aside at least two hours to keep another group informed: his Twitter followers. Dr. Wachter, 62 years old, is part of a growing group of scientists and public-health officials who are increasingly active and drawing large audiences on social media. They say they feel a moral obligation to provide credible information online and steer the conversation away from dubious claims, such as those in "Plandemic," a video espousing Covid-19 conspiracy theories that drew millions of views last week. [...]

Dr. Wachter typically writes his tweets in threads, long strings of posts on a single topic or idea; on Wednesday, he posted about masks. [...] To compose his tweets, Dr. Wachter keeps a document open throughout the day, where he drops in material he believes could be relevant to his followers. He starts writing posts between 4 and 6 p.m.; his wife, a journalist, often proofreads them, he says. His tweets post between 7 and 8 p.m. The doctors feel like they "have an obligation to put out information that is as correct as it can be," says Dr. Wachter. This is important during amidst a pandemic, especially after a new paper in the journal Nature this week found that antivaccination views are drowning out the more mainstream voices online, "partly due to the ways antivaccination advocates interact with some users of social media platforms," reports the WSJ.

"As a result, researchers predict, antivaccination views 'will dominate in a decade.'"

A new hydroxychloroquine study -- "the largest to date" -- was published Thursday in the prestigious New England Journal of Medicine. It concluded that Covid-19 patients taking the drug "do not fare better than those not receiving the drug," reports Time: Dr. Neil Schluger, chief of the division of pulmonary, allergy and critical care medicine at Columbia, and his team studied more than 1,300 patients admitted to New York-Presbyterian Hospital-Columbia University Irving Medical Center for COVID-19. Some received hydroxychloroquine on an off-label basis, a practice that allows doctors to prescribe a drug that has been approved for one disease to treat another — in this case, COVID-19. About 60% of the patients received hydroxychloroquine for about five days.

They did not show any lower rate of needing ventilators or a lower risk of dying during the study period compared to people not getting the drug.

"We don't think at this point, given the totality of evidence, that it is reasonable to routinely give this drug to patients," says Schluger. "We don't see the rationale for doing that." While the study did not randomly assign people to receive the drug or placebo and compare their outcomes, the large number of patients involved suggests the findings are solid. Based on the results, Schluger says doctors at his hospital have already changed their advice about using hydroxychloroquine to treat COVID-19. "Our guidance early on had suggested giving hydroxychloroquine to hospitalized patients, and we updated that guidance to remove that suggestion," he says.
In another study conducted at U.S. veterans hospitals where severely ill patients were given hydroxychloroquine, "the drug was found to be of no use against the disease and potentially harmful when given in high doses," reports the Chicago Tribune.

They also report that to firmly establish whether the drug has any effect, the Bill and Melinda Gates Foundation is now funding a randomized, controlled trial at six medical institutions of hundreds of people who've tested positive for Covid-19.