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Scientists calculate incubation period of coronavirus
About 97.5 percent of people who develop symptoms will do so within 11.5 days, according to the new study.
- The incubation period of a virus is the amount of time it takes for a person to show symptoms after infection.
- A new study examined 181 cases of SARS-CoV-2 in China, finding that the mean incubation period is 5.1 days.
- The results suggest that a quarantine period of 14 days is reasonable.
It takes an average of 5.1 days for a person infected with the new coronavirus to show symptoms, according to recent research from Johns Hopkins University. Fortunately, an average incubation period of 5.1 days means that a 14-day quarantine period, which is used by the U.S. and other nations, is an appropriate amount of time to monitor people for the development of COVID-19.
"Based on our analysis of publicly available data, the current recommendation of 14 days for active monitoring or quarantine is reasonable," epidemiologist Justin Lessler from Johns Hopkins Bloomberg School of Public Health told Johns Hopkins University's HUB.That's the good news. But the findings, published March 10 in the journal Annals of Internal Medicine, also highlight one of the most pernicious aspects of the novel coronavirus: It can take days for people to realize they're infected and contagious.
Carl Court / Staff
The study estimated that the median incubation period of the SARS-CoV-2 coronavirus is 5.1 days, and that 97.5 percent of people who develop symptoms will do so within 11.5 days. However, approximately 2.5 percent of people with the virus seem to develop symptoms after 11.5 days. That means a 14-day quarantine might not be 100 percent effective. In other words, for every 10,000 people quarantined, about 101 would develop symptoms after being released, according to the researchers.
"Whether this rate is acceptable depends on the expected risk for infection in the population being monitored and considered judgment about the cost of missing cases," the researchers wrote. "Combining these judgments with the estimates presented here can help public health officials to set rational and evidence-based COVID-19 control policies."
Chung Sung-Jun / Staff
The study was based on 181 cases of COVID-19 reported in China before February 24. To create a model of incubation period distribution, the researchers looked at metrics like probable time of exposure, symptom onset, fever onset, and detection by authorities. The results showed that the incubation period of SARS-CoV-2 roughly matches that of past infectious diseases like SARS and MERS, but is a bit longer than the incubation period of the flu, which is one to four days.
Public health officials use estimates like these to determine the length of quarantines, which help to contain and track the spread of a virus. One of the most important functions of a quarantine — or really any social distancing measure — is that it helps to prevent hospitals from being overwhelmed by sick and infected patients.
If you only learn one thing about #COVID19 today make it this: everyone's job is to help FLATTEN THE CURVE. With th… https://t.co/7kEDRf1ffp— Dr Siouxsie Wiles (@Dr Siouxsie Wiles)1583692285.0
"From a US standpoint, you want to prevent any place from becoming the next Wuhan," Tom Frieden, who led the CDC under President Barack Obama, told Vox. "What that means is even if we're not able to prevent widespread transmission, we want to prevent explosive transmission and anything that overwhelms the health care system."
Slowing the spread of a virus is also referred to as flattening the curve. As Dr. Siouxsie Wiles posted on Twitter, flattening the curve is a responsibility that falls not only on government, but also on individuals. So, be sure to brush up on the best ways to prevent the contraction of the new coronavirus, and learn how it spreads from person to person.
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Scientists are using bioelectronic medicine to treat inflammatory diseases, an approach that capitalizes on the ancient "hardwiring" of the nervous system.
- Bioelectronic medicine is an emerging field that focuses on manipulating the nervous system to treat diseases.
- Clinical studies show that using electronic devices to stimulate the vagus nerve is effective at treating inflammatory diseases like rheumatoid arthritis.
- Although it's not yet approved by the US Food and Drug Administration, vagus nerve stimulation may also prove effective at treating other diseases like cancer, diabetes and depression.
The nervous system’s ancient reflexes<p>You accidentally place your hand on a hot stove. Almost instantaneously, your hand withdraws.</p><p>What triggered your hand to move? The answer is <em>not</em> that you consciously decided the stove was hot and you should move your hand. Rather, it was a reflex: Skin receptors on your hand sent nerve impulses to the spinal cord, which ultimately sent back motor neurons that caused your hand to move away. This all occurred before your "conscious brain" realized what happened.</p><p>Similarly, the nervous system has reflexes that protect individual cells in the body.</p><p>"The nervous system evolved because we need to respond to stimuli in the environment," said Dr. Tracey. "Neural signals don't come from the brain down first. Instead, when something happens in the environment, our peripheral nervous system senses it and sends a signal to the central nervous system, which comprises the brain and spinal cord. And then the nervous system responds to correct the problem."</p><p>So, what if scientists could "hack" into the nervous system, manipulating the electrical activity in the nervous system to control molecular processes and produce desirable outcomes? That's the chief goal of bioelectronic medicine.</p><p>"There are billions of neurons in the body that interact with almost every cell in the body, and at each of those nerve endings, molecular signals control molecular mechanisms that can be defined and mapped, and potentially put under control," Dr. Tracey said in a <a href="https://www.youtube.com/watch?v=AJH9KsMKi5M" target="_blank">TED Talk</a>.</p><p>"Many of these mechanisms are also involved in important diseases, like cancer, Alzheimer's, diabetes, hypertension and shock. It's very plausible that finding neural signals to control those mechanisms will hold promises for devices replacing some of today's medication for those diseases."</p><p>How can scientists hack the nervous system? For years, researchers in the field of bioelectronic medicine have zeroed in on the longest cranial nerve in the body: the vagus nerve.</p>
The vagus nerve<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTYyOTM5OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0NTIwNzk0NX0.UCy-3UNpomb3DQZMhyOw_SQG4ThwACXW_rMnc9mLAe8/img.jpg?width=1245&coordinates=0%2C0%2C0%2C0&height=700" id="09add" class="rm-shortcode" data-rm-shortcode-id="f38dbfbbfe470ad85a3b023dd5083557" data-rm-shortcode-name="rebelmouse-image" data-width="1245" data-height="700" />
Electrical signals, seen here in a synapse, travel along the vagus nerve to trigger an inflammatory response.
Credit: Adobe Stock via solvod<p>The vagus nerve ("vagus" meaning "wandering" in Latin) comprises two nerve branches that stretch from the brainstem down to the chest and abdomen, where nerve fibers connect to organs. Electrical signals constantly travel up and down the vagus nerve, facilitating communication between the brain and other parts of the body.</p><p>One aspect of this back-and-forth communication is inflammation. When the immune system detects injury or attack, it automatically triggers an inflammatory response, which helps heal injuries and fend off invaders. But when not deployed properly, inflammation can become excessive, exacerbating the original problem and potentially contributing to diseases.</p><p>In 2002, Dr. Tracey and his colleagues discovered that the nervous system plays a key role in monitoring and modifying inflammation. This occurs through a process called the <a href="https://www.nature.com/articles/nature01321" target="_blank" rel="noopener noreferrer">inflammatory reflex</a>. In simple terms, it works like this: When the nervous system detects inflammatory stimuli, it reflexively (and subconsciously) deploys electrical signals through the vagus nerve that trigger anti-inflammatory molecular processes.</p><p>In rodent experiments, Dr. Tracey and his colleagues observed that electrical signals traveling through the vagus nerve control TNF, a protein that, in excess, causes inflammation. These electrical signals travel through the vagus nerve to the spleen. There, electrical signals are converted to chemical signals, triggering a molecular process that ultimately makes TNF, which exacerbates conditions like rheumatoid arthritis.</p><p>The incredible chain reaction of the inflammatory reflex was observed by Dr. Tracey and his colleagues in greater detail through rodent experiments. When inflammatory stimuli are detected, the nervous system sends electrical signals that travel through the vagus nerve to the spleen. There, the electrical signals are converted to chemical signals, which trigger the spleen to create a white blood cell called a T cell, which then creates a neurotransmitter called acetylcholine. The acetylcholine interacts with macrophages, which are a specific type of white blood cell that creates TNF, a protein that, in excess, causes inflammation. At that point, the acetylcholine triggers the macrophages to stop overproducing TNF – or inflammation.</p><p>Experiments showed that when a specific part of the body is inflamed, specific fibers within the vagus nerve start firing. Dr. Tracey and his colleagues were able to map these relationships. More importantly, they were able to stimulate specific parts of the vagus nerve to "shut off" inflammation.</p><p>What's more, clinical trials show that vagus nerve stimulation not only "shuts off" inflammation, but also triggers the production of cells that promote healing.</p><p>"In animal experiments, we understand how this works," Dr. Tracey said. "And now we have clinical trials showing that the human response is what's predicted by the lab experiments. Many scientific thresholds have been crossed in the clinic and the lab. We're literally at the point of regulatory steps and stages, and then marketing and distribution before this idea takes off."<br></p>
The future of bioelectronic medicine<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTYxMDYxMy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNjQwOTExNH0.uBY1TnEs_kv9Dal7zmA_i9L7T0wnIuf9gGtdRXcNNxo/img.jpg?width=980" id="8b5b2" class="rm-shortcode" data-rm-shortcode-id="c005e615e5f23c2817483862354d2cc4" data-rm-shortcode-name="rebelmouse-image" data-width="2000" data-height="1125" />
Vagus nerve stimulation can already treat Crohn's disease and other inflammatory diseases. In the future, it may also be used to treat cancer, diabetes, and depression.
Credit: Adobe Stock via Maridav<p>Vagus nerve stimulation is currently awaiting approval by the US Food and Drug Administration, but so far, it's proven safe and effective in clinical trials on humans. Dr. Tracey said vagus nerve stimulation could become a common treatment for a wide range of diseases, including cancer, Alzheimer's, diabetes, hypertension, shock, depression and diabetes.</p><p>"To the extent that inflammation is the problem in the disease, then stopping inflammation or suppressing the inflammation with vagus nerve stimulation or bioelectronic approaches will be beneficial and therapeutic," he said.</p><p>Receiving vagus nerve stimulation would require having an electronic device, about the size of lima bean, surgically implanted in your neck during a 30-minute procedure. A couple of weeks later, you'd visit, say, your rheumatologist, who would activate the device and determine the right dosage. The stimulation would take a few minutes each day, and it'd likely be unnoticeable.</p><p>But the most revolutionary aspect of bioelectronic medicine, according to Dr. Tracey, is that approaches like vagus nerve stimulation wouldn't come with harmful and potentially deadly side effects, as many pharmaceutical drugs currently do.</p><p>"A device on a nerve is not going to have systemic side effects on the body like taking a steroid does," Dr. Tracey said. "It's a powerful concept that, frankly, scientists are quite accepting of—it's actually quite amazing. But the idea of adopting this into practice is going to take another 10 or 20 years, because it's hard for physicians, who've spent their lives writing prescriptions for pills or injections, that a computer chip can replace the drug."</p><p>But patients could also play a role in advancing bioelectronic medicine.</p><p>"There's a huge demand in this patient cohort for something better than they're taking now," Dr. Tracey said. "Patients don't want to take a drug with a black-box warning, costs $100,000 a year and works half the time."</p><p>Michael Dowling, president and CEO of Northwell Health, elaborated:</p><p>"Why would patients pursue a drug regimen when they could opt for a few electronic pulses? Is it possible that treatments like this, pulses through electronic devices, could replace some drugs in the coming years as preferred treatments? Tracey believes it is, and that is perhaps why the pharmaceutical industry closely follows his work."</p><p>Over the long term, bioelectronic approaches are unlikely to completely replace pharmaceutical drugs, but they could replace many, or at least be used as supplemental treatments.</p><p>Dr. Tracey is optimistic about the future of the field.</p><p>"It's going to spawn a huge new industry that will rival the pharmaceutical industry in the next 50 years," he said. "This is no longer just a startup industry. [...] It's going to be very interesting to see the explosive growth that's going to occur."</p>
Master negotiator Chris Voss breaks down how to get what you want during negotiations.
- Former FBI negotiator Chris Voss explains how forced empathy is a powerful negotiating tactic.
- The key is starting a sentence with "What" or "How," causing the other person to look at the situation through your eyes.
- What appears to signal weakness is turned into a strength when using this tactic.
Choose your battles<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzQ1OTQ2NC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxNDgwMTA5OH0.BP2vZe7gZdiaE_KA5Otr4pzYmAqpFQUGSRSVr28Bipo/img.jpg?width=1245&coordinates=0%2C90%2C0%2C32&height=700" id="46a4d" class="rm-shortcode" data-rm-shortcode-id="912a183929345986b45c3455a6f369f5" data-rm-shortcode-name="rebelmouse-image" alt="Aikido Morihei Ueshiba" data-width="1245" data-height="700" />
Aikido Morihei Ueshiba (1883 - 1969, standing, centre left), founder of the Japanese martial art of aikido, demonstrating his art with a follower, at the opening ceremony of the newly-opened aikido headquarters, Hombu Dojo, in Shinjuku, Tokyo, 1967.
Credit: Keystone/Hulton Archive/Getty Images<p>Online debates often amount to little more than frustrated individuals pulling out their hair. In his book, <a href="https://www.amazon.com/dp/0062339346?tag=bigthink00-20&linkCode=ogi&th=1&psc=1" target="_blank">"Against Empathy,"</a> Yale psychology professor Paul Bloom writes that effective altruists are able to focus on what really matters in everyday life.</p><p>For example, he compares politics to sports. Rooting for your favorite team isn't based in rationality. If you're a Red Sox fan, Yankees stats don't matter. You just want to destroy them. This, he believes, is how most people treat politics. "They don't care about truth because, for them, it's not really about truth."</p><p>Bloom writes that if his son believed our ancestors rode dinosaurs, it would horrify him, but "I can't think of a view that matters less for everyday life." We have to strive for rationality when the stakes are high. When involved in real decision-making processes that will affect their life, people are better able to express ideas and make arguments, and are more receptive to opposing ideas. </p><p>Because we "become inured to problems that seem unrelenting," it's imperative to make the problem seem immediate. As Voss says, giving the other side "the illusion of control" is one way of accomplishing this, as it forces them to take action. When people feel out of control, negotiations are impossible. People dig their heels in and refuse to budge. </p><p>What seems to be weakness is actually a strength. To borrow another martial arts metaphor, negotiations are like aikido: using your opponent's force against them while also protecting them from injury. Forcing empathy is one way to accomplish this task. You may get more than you ask for without the other side ever realizing they surrendered anything.</p><p>--</p><p><em>Stay in touch with Derek on <a href="http://www.twitter.com/derekberes" target="_blank">Twitter</a>, <a href="https://www.facebook.com/DerekBeresdotcom" target="_blank">Facebook</a> and <a href="https://derekberes.substack.com/" target="_blank">Substack</a>. His next book is</em> "<em>Hero's Dose: The Case For Psychedelics in Ritual and Therapy."</em></p>
3 Tips on Negotiations, with FBI Negotiator Chris Voss<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="b86d518e9f0c9f9d7a7c686e07798152"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/-FLlBchonwM?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
"The Expanse" is the best vision I've ever seen of a space-faring future that may be just a few generations away.
- Want three reasons why that headline is justified? Characters and acting, universe building, and science.
- For those who don't know, "The Expanse" is a series that's run on SyFy and Amazon Prime set about 200 years in the future in a mostly settled solar system with three waring factions: Earth, Mars, and Belters.
- No other show I know of manages to use real science so adeptly in the service of its story and its grand universe building.
Credit: "The Expanse" / Syfy<p>Now, I get it if you don't agree with me. I love "Star Trek" and I thought "Battlestar Galactica" (the new one) was amazing and I do adore "The Mandalorian". They are all fun and important and worth watching and thinking about. And maybe you love them more than anything else. But when you sum up the acting, the universe building, and the use of real science where it matters, I think nothing can beat "The Expanse". And with a <a href="https://www.rottentomatoes.com/tv/the_expanse" target="_blank">Rotten Tomato</a> average rating of 93%, I'm clearly not the only one who feels this way.</p><p>Best.</p><p>Show.</p><p>Ever. </p>
Contrary to what some might think, the brain is a very plastic organ.