Coronavirus reinfection cases: what we know so far – and the vital missing clues
by ilene - October 19th, 2020 1:48 am
Coronavirus reinfection cases: what we know so far – and the vital missing clues
By Sheena Cruickshank, University of Manchester
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As President Trump claims that he is immune to COVID-19 and isolated reports emerge of reinfection, what is the truth about immunity to COVID-19?
To date, there have been six published cases of COVID-19 reinfection, with various other unverified accounts from around the world. Although this is a comparably small fraction of the millions of people known to have been infected, should we be concerned? To unpick this puzzle, we must first consider what we mean by immunity.
How immunity works
When we are infected with any pathogen, our immune system quickly responds to try to contain the threat and minimise any damage. Our first line of defence is from immune cells, known as innate cells. These cells are not usually enough to eliminate a threat, which is where having a more flexible “adaptive” immune response comes into play – our lymphocytes.
Lymphocytes come in two main varieties: B lymphocytes, which make antibodies, and T lymphocytes, which include cells that directly kill the germy invaders.
As antibodies are readily measured in blood, they are often used to indicate a good adaptive immune response. However, over time, antibodies levels in our blood wane, but this doesn’t necessarily mean protection is lost. We retain some lymphocytes that know how to deal with the threat – our memory cells. Memory cells are remarkably long-lived, patrolling our body, ready to spring into action when needed.
Vaccines work by creating memory cells without the risk of a potentially fatal infection. In an ideal world, it would be relatively easy to create immunity, but it’s not always that straightforward.
Although our immune system has evolved to deal with a huge variety of pathogens, these germs have also evolved to hide from the immune system. This arms race means that some pathogens such as malaria or HIV are very tricky to deal with.
Infections that have spilled over from animals -– zoonotic diseases –- are also challenging for our immune system because they can be completely novel. The virus that causes COVID-19 is such a zoonotic disease, originating…
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Colleges and the Thanksgiving COVID-19 risk: Fauci’s right – holiday plans may have to change
by ilene - October 16th, 2020 3:13 pm
Colleges and the Thanksgiving COVID-19 risk: Fauci’s right – holiday plans may have to change
College students are making plans to head home for the holidays at the same time U.S. COVID-19 case numbers are rising. William Campbell/Getty Images
Courtesy of Walter Thomas Casey II, Texas A&M University-Texarkana; Marcia G. Ory, Texas A&M University, and Rebecca S.B. Fischer, Texas A&M University
Dr. Anthony Fauci, the nation’s leading infectious disease expert, warned this week that families may need to change their Thanksgiving plans to keep everyone safe from the coronavirus. The head of the Centers for Disease Control and Prevention, Robert Redfield, expressed similar concerns in a call with governors.
There has been an alarming increase in COVID-19 cases in most states in recent weeks, and we have seen cases rise in college towns in particular. Colder weather means more activities are moving indoors, where the virus can circulate. And people who have been socially isolated for months feel desperate for connection.
As the holidays approach, one important question is what impact sending college students home for Thanksgiving will have on their home communities.
The Public Health Response Team at Texas A&M University, which the three of us serve on, has been documenting COVID-19 trends in Texas for the past six months and forecasting disease spread and the impacts on hospitals. With new cases ticking upward, we have been concerned about what the holidays will bring.
Dual hot spots
In Texas, the most densely populated counties have a higher proportion of documented SARS-CoV-2 infections, and they contain a majority of the state’s colleges and universities. The intersection of these features creates challenges for controlling COVID-19.
Many of these counties were already COVID-19 hot spots before students returned for the fall semester. In more crowded communities, the chance of random exposure to someone with COVID-19 is a lot less random and a lot more certain.
Reopening the campuses brought in an age demographic known to harbor the virus but often with only mild symptoms or no symptoms at…
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Exposure to man-made chemicals influences genes controlling aging, immune system and metabolism
by ilene - October 15th, 2020 6:50 pm
Exposure to man-made chemicals influences genes controlling aging, immune system and metabolism
Most genes in the human body can be disrupted by man-made chemicals. Göran Andersson/Getty Images
Courtesy of Alexander Suvorov, University of Massachusetts Amherst
Today humans are exposed to thousands of man-made chemicals. Yet the effects on people’s health are still not fully understood.
In 2020 the number of registered chemicals reached 167 million. Every day people are exposed to them through food, water, contaminated air, drugs, cosmetics and other man-made substances. Less than 1% of these chemicals were tested for toxicity, and those that were tested demonstrate ability to disrupt almost every biological process in our body. Can we infer how cumulative exposures shape our health?
I am an environmental toxicologist studying effects of man-made chemicals on our health. I decided to develop a computational approach to objectively compare sensitivity of all genes to all chemicals and identify the most vulnerable biological processes.
Unbiased approach
For our study, my research colleagues and I used data from the Comparative Toxicogenomic Database. The Comparative Toxicogenomic Database collects information from thousands of published studies on how chemicals change the activity of genes. Genes are sections of DNA that encode proteins which perform a broad range of functions in cells, from building tissues to metabolizing nutrients. When chemicals affect genes, that results in increased or decreased production of proteins.
Modern methods of molecular biology can detect changes in activity of all genes in the genome in response to a chemical insult. I developed an approach that overlays lists of altered genes from different studies to calculate how many times each gene was affected. The resulting numbers reflect sensitivities of genes to chemicals generally.
Using 2,169 studies on mice, rats, humans and their cells, my research group ranked the sensitivity of 17,338 genes to chemical exposures. These studies tested the impact of 1,239 diverse chemicals ranging from prescription drugs to environmental pollutants.
At the next step we ran tests to ensure that this sample of over 1,000 chemicals was large enough to reliably represent all classes of man-made chemicals people are exposed to. To do so,…
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279,700 extra deaths in the US so far in this pandemic year
by ilene - October 14th, 2020 5:45 pm
279,700 extra deaths in the US so far in this pandemic year
A girl views the body of her father, who died of COVID-19, while mourners who can’t visit in person are onscreen. Joe Raedle/Getty Images News via Getty Images
Courtesy of Ronald D. Fricker Jr., Virginia Tech
The Conversation, CC BY-ND
The number of deaths in the United States through September 2020 is at least 10% and likely 13% higher than it would have been if the coronavirus pandemic had never happened, according to Centers for Disease Control and Prevention data. Conservatively, that’s at least 224,173 deaths and probably as many as 279,700 deaths above what was expected, just for the first nine months of the year. That’s 24,000 to 79,000 extra fatalities above the number of deaths attributed to COVID-19.
Tracking deaths
When someone dies, the death certificate records an immediate cause of death, along with up to three underlying conditions that “initiated the events resulting in death.” The certificate is filed with the local health department, and the details are reported to the National Center for Health Statistics.
As part of the National Vital Statistics System, the National Center for Health Statistics then uses this information in various ways, such as tabulating the leading causes of death in the United States. Currently, heart disease is the leading cause of death, followed by cancer. COVID-19 is now the third-largest cause of death for 2020.
Projecting from the past
To calculate excess deaths requires a comparison to what would have occurred if COVID-19 had not existed. Obviously, it’s not possible to observe what didn’t happen, but it is possible to estimate it using historical data. The CDC does this using a statistical model based on the previous three years of mortality data, incorporating seasonal trends as well as adjustments for data-reporting delays.
So, looking at what happened over the past three years, the CDC projects what might have been. By using a statistical model, they are also able to calculate the…
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Can we actually learn to live with coronavirus? Not until we have a vaccine
by ilene - October 14th, 2020 2:54 am
Can we actually learn to live with coronavirus? Not until we have a vaccine
Courtesy of Sarah Pitt, University of Brighton
As we move into the last quarter of 2020, the virus that has defined this troubled year is showing no signs of going away. In the absence of a vaccine or a broadly effective treatment, some are now saying that we must learn to live with COVID-19. But what does that actually look like?
It’s a complicated question that boils down to this: Should we allow SARS-CoV-2 to spread through most of the population while shielding all the elderly and those at high risk of serious disease, thus creating some level of underlying immunity in the population? Or is it better to keep up with the control measures and aim for the elimination of the virus?
In trying to answer the question, the concept of “herd immunity” – when around 60% of the population is immune to a disease – is often invoked. But this term is not well understood. Control of an infectious disease through build-up of natural immunity in the population has never been achieved before. Herd immunity works through targeted vaccination, and we do not yet have a vaccine for COVID-19.
Viruses and immunity
Take the example of smallpox – a very infectious, scary disease and the only human virus we have ever eradicated. Unlike COVID-19, people who caught the virus always showed symptoms, so they could be found and isolated. Anyone who did not die would have life-long protection.
But we only completely rid the world of it through a coordinated vaccination campaign. This was the only way that high enough levels of protection could be achieved across the world to reach the threshold for herd immunity.
Herd immunity can’t happen without widespread vaccination.
About a quarter of all common colds are caused by types of coronavirus. Since SARS-CoV-2 is also a coronavirus, could there be a similar protective crossover? We don’t know how long the protection to any coronavirus lasts after you recover,…
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‘What do you mean, it was a false positive?’ Making sense of COVID-19 tests and terminology
by ilene - October 13th, 2020 7:03 pm
'What do you mean, it was a false positive?' Making sense of COVID-19 tests and terminology
Friaaz Azeez gets tested for COVID-19 by a health-care worker at a pop-up testing centre at the Islamic Institute of Toronto in Scarborough, Ont., on May 29, 2020. THE CANADIAN PRESS/Nathan Denette
Courtesy of Priyanka Gogna, Queen's University, Ontario
During the COVID-19 pandemic, words and phrases that have typically been limited to epidemiologists and public health professionals have entered the public sphere. Although we’ve rapidly accepted epidemiology-based news, the public hasn’t been given the chance to fully absorb what all these terms really mean.
As with all disease tests, a false positive result on a COVID-19 test can cause undue stress on individuals as they try to navigate their diagnosis, take days off work and isolate from family. One high-profile example was Ohio Governor Mike DeWine whose false positive result led him to cancel a meeting with President Donald Trump.
False negative test results are even more dangerous, as people may think it is safe and appropriate for them to engage in social activities. Of course, factors such as the type of test, whether the individual had symptoms before being tested and the timing of the test can also impact how well the test predicts whether someone is infected.
Sensitivity and specificity are two extremely important scientific concepts for understanding the results of COVID-19 tests.
In the epidemiological context, sensitivity is the proportion of true positives that are correctly identified. If 100 people have a disease, and the test identifies 90 of these people as having the disease, the sensitivity of the test is 90 per cent.
A laboratory technical assistant at LifeLabs handles a specimen to be tested for COVID-19 after scanning its barcode upon receipt at the company’s lab, in Surrey, B.C., on March 26, 2020. THE CANADIAN PRESS/Darryl Dyck
Specificity is the ability of a test to correctly identify those without the disease. If 100 people don’t have the disease, and the test correctly identifies 90 people as disease-free, the test has a…
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Political leaders’ attitudes toward COVID-19 risk are highly infectious in a polarized nation – just like climate change denial
by ilene - October 13th, 2020 3:24 pm
Political leaders' attitudes toward COVID-19 risk are highly infectious in a polarized nation – just like climate change denial
President Trump’s messages discounting mask-wearing have worried public health professionals. AP Photos/Alex Brandon
Courtesy of Wanyun Shao, University of Alabama
When President Donald Trump announced he was leaving the hospital after being treated for COVID-19, he sent his supporters a message: “Don’t be afraid of COVID. Don’t let it dominate your life,” he tweeted. A few hours later at the White House, he pulled off his mask in dramatic fashion for the cameras and stuffed it in his pocket.
That message on Oct. 5 and his subsequent words and actions – including telling supporters at a Florida campaign rally on Oct. 12, “if you want to get out there, get out there,” and that he and wanted to kiss everyone in the tightly packed audience – flew in the face of health professionals’ warnings.
Over 215,000 people have died from COVID-19 in the U.S., and the country faces a high risk of a surge in cases this fall. Wearing face masks and social distancing can help stop the virus’s spread.
Coming from a political leader, Trump’s words and behaviors downplaying the risks are potent. My research as a professor who studies risk perception shows that in a highly polarized environment, political leaders’ rhetoric can play a significant role in shaping risk perceptions among their loyal followers.
If the leader deems the risk to be small, his or her supporters will be more likely to share that view. If the leader does not strictly follow rules on wearing masks and social distancing, the supporters are more than likely to follow suit.
This pattern has been confirmed in recent months by evidence that U.S. counties with more Trump voters see fewer people social distancing. It also echoes what I and other researchers have found with the politicization of climate change.
Echoes of climate change denial
Climate change is another area where politics can influence the perception of risk and how to respond to it. Two decades of social science research has…
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Dan’s Covid Charts: Blue States vs. Red States Over Time
by ilene - October 13th, 2020 3:16 am
The trend of lower Covid-19 case numbers per capita in blue states compared to red states isn't itself surprising, but the magnitude of the differences may be. You can visualize the evolving differences in case loads by watching the infection's progression, as measured by cases per capita, at Dan's website.
[Visit Dan’s COVID Charts to see these amazing animated charts and more. Fortunately, Dan broke his Twitter hiatus to share his work.]
People say I should break my 12-year Twitter hiatus to share my latest animated COVID chart. It compares state cases factoring in partisanship since June 1, when science had proven methodology as to how to stop the spread after the initial sucker punch. https://t.co/FvifckA30f
— dangoodspeed (@dangoodspeed) October 13, 2020
Screenshot of the charts showing the states which have fared the best and the states that have fared the worst as of October 10, 2020 — as you can see, the blue states are highly clustered among the 25 best states (fewest cases per capita) and the red states are clustered among the 25 worst states (most cases):
On June 1, 20, the situation was quite different — the pattern, resulting from how the states handled the pandemic, had not yet evolved. Here are the "before" pictures:
Thanks, Dan!
Follow Dan on Twitter here.
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Timeline to the New Normal
by ilene - October 12th, 2020 4:00 am
Timeline to the New Normal
Courtesy of John Mauldin
Like everyone else, I am weary of this pandemic mess. I want to travel freely, enjoy dinner with friends, hug, and shake hands.
And, of course, I want everyone who lost jobs and businesses to get them back. I wasn’t thrilled with the economy a year ago, but I’d take it again in a heartbeat.
Alas, that’s not going to happen. The recovery in front of us will be slower than we like. History shows improvement over time. Extreme poverty keeps dropping significantly every decade, although this year was a major setback. But that trend will eventually return. We will get through this. Yet the world on the other side will be different. In some ways, it will be better, primarily because of technology innovation, but don’t expect the old world of 2019 to return. It’s gone.
Having a general idea of where we are going is great, but how we get there is important, too. Today I want to make some informed speculation about how the next year will unfold. We’re going to reach some key decision points in the coming months and you’ll make better decisions if you think about them before we get there.
In a way, this is like getting the full schedule when your child goes to school. When you know when their vacations are, when grades come out, when games are played, it’s easier to do planning. Sometimes those dates are inconvenient, but it’s better to know the schedule.
Landmarks Ahead
I’ll start with some info from an excellent article from STAT, the healthcare news service founded by hedge fund titan John Henry. I find its pandemic coverage far more enlightening than the mainstream media.
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On September 22, STAT ran a long article titled “The Road Ahead.” It lists 30 key moments that could either change the pandemic’s direction in the US, or at least give us important information. At this point no one knows what any of them will bring, but they are worth considering. I’ll share just a few.
October 2020: More Treatments Arrive
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‘What goes around comes around,’ or what Greek mythology says about Donald Trump
by ilene - October 8th, 2020 5:25 pm
'What goes around comes around,' or what Greek mythology says about Donald Trump
Donald Trump’s helicopter landing at the White House, Oct. 5, as he returns from being hospitalized at Walter Reed. Liu Jie/Xinhua via Getty Images
Courtesy of Rachel Hadas, Rutgers University Newark
It’s hard to process the news of the president’s positive COVID-19 diagnosis without having recourse to some kind of mythological system, some larger frame of reference.
Karma, wrote one journalist, and then reproached himself for the ungenerous thought. Or perhaps it was simple irony on display when, Washington Post reporters wrote, “President Trump contracted the novel coronavirus after months in which he and people around him…avoided taking basic steps to prevent the virus’s spread.”
All these reactions make sense. If there’s one thing we know about a virus that’s still mysterious in many ways, it’s that this coronavirus is expert at going around.
And as a classics scholar, I can assure you: What goes around comes around. Greek mythology provides insight to help us understand today’s chaos.
Failure to see until too late
Many years ago, my high school English teachers put a lot of stress on terms like foreshadowing, climax and denouement. All these words marked points along a steep curve of the development of a story: rising action, turning point, falling action.
There was also a lot of emphasis, as we discussed plots, on a term I then found harder to understand: pride. Pride: arrogance; an exaggerated sense of self-worth. Pride tended to be followed by catastrophe – that falling action again.
As a high school student, I tended to confuse pride with vanity, with narcissistic preening; the tragic penalty of vanity seemed exaggeratedly severe.
What does “pride” really mean? The Greek word it translates is hubris, and pride doesn’t quite cover the range of the meaning of hubris. Vanity may well be part of hubris, but a more crucial sense of the word is terrible judgment, gross overconfidence, blindness, obtuseness, a failure to see what is staring you in the face – a failure to see it until it’s too late.
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Philip R. Davis is a founder Phil's Stock World, a stock and options trading site that teaches the art of options trading to newcomers and devises advanced strategies for expert traders...
Ilene is editor and affiliate program
coordinator for PSW.