Posted on 04/10/2020 4:18:44 PM PDT by daniel1212
Many infectious diseases are more common during specific seasons. “It’s a very old question, but it’s not very well studied,” Martinez says....But what’s known about other diseases doesn’t offer much support for the idea that COVID-19 will suddenly disappear over the next few weeks...
Different diseases have different patterns. Some peak in early or late winter, others in spring, summer, or fall. Some diseases have different seasonal peaks depending on latitude. And many have no seasonal cycle at all. So no one knows whether SARS-CoV-2 will change its behavior come spring...
Investigating a hypothesis over several seasons can take 2 or 3 years. “Postdocs can only get one experiment done and it can be a career killer,” Loudon says. The field is also plagued by confounding variables. “All kinds of things are seasonal, like Christmas shopping,” says epidemiologist Scott Dowell..
Many focus on the relationships between the pathogen, the environment, and human behavior. Influenza, for example, might do better in winter because of factors such as humidity, temperature, people being closer together, or changes in diets and vitamin D levels.
Martinez is studying another theory, which Dowell’s paper posited but didn’t test: The human immune system may change with the seasons, becoming more resistant or more susceptible to different infections based on how much light our bodies experience.
The calendar of epidemics
At least 68 infectious diseases are seasonal, according to a 2018 paper by Micaela Martinez of Columbia University. But they’re not in sync, and seasonality varies by location. In this graphic, based on U.S. federal and state health records, each bubble represents the percentage of annual cases that occurred in each month. (The data are old because many diseases declined—in some cases to zero—after introduction of vaccines.)
[see map at site ]
Except in the equatorial regions, respiratory syncytial virus (RSV) is a winter disease, Martinez wrote, but chickenpox favors the spring. Rotavirus peaks in December or January in the U.S. Southwest, but in April and May in the Northeast. Genital herpes surges all over the country in the spring and summer, whereas tetanus favors midsummer; gonorrhea takes off in the summer and fall, and pertussis has a higher incidence from June through October. Syphilis does well in winter in China, but typhoid fever spikes there in July. Hepatitis C peaks in winter in India but in spring or summer in Egypt, China, and Mexico. Dry seasons are linked to Guinea worm disease and Lassa fever in Nigeria and hepatitis A in Brazil.
Seasonality is easiest to understand for diseases spread by insects that thrive during rainy seasons, such as African sleeping sickness, chikungunya, dengue, and river blindness. For most other infections, there’s little rhyme or reason to the timing.
To Nathanson, this variation suggests human activity—such as children returning to school or people huddling indoors in cold weather—doesn’t drive seasonality. “Most viruses get transmitted between kids, and under those circumstances, you’d expect most of the viruses to be in sync,” he says...
Ramalingam’s team also studied the relationship between viral abundance and daily weather changes. Influenza and RSV both did best when the change in relative humidity over a 24-hour period was lower than the average (a 25% difference). “There’s something about the lipid envelope that’s more fragile” when the humidity changes sharply, Ramalingam concludes.... absolute humidity drops sharply in winter, because cold air holds less water vapor...
SARS emerged in late 2002 and was driven out of the human population in the summer of 2003 through intensive containment efforts. MERS sporadically jumps from camels to humans and has caused outbreaks in hospitals, but never widespread human-to-human transmission like COVID-19. Neither virus circulated for long enough, on a wide enough scale, for any seasonal cycle to emerge...
People seeking help for pandemic influenza in Brazil in July 2009, when cold weather boosted the spread of the disease. JEFFERSON BERNARDES/AFP/Getty Images Why do dozens of diseases wax and wane with the seasons—and will COVID-19?
By Jon CohenMar. 13, 2020 , 7:41 PM
On a December afternoon, 13 days before the winter solstice, six men and women checked into the Surrey Clinical Research Facility, part of the University of Surrey in the United Kingdom. After having their noses swabbed to check for 16 different respiratory viruses, they walked into their own temperature-regulated rooms and, for 24 hours, each person stayed in a semirecumbent position in dim light. Nurses placed a cannula into a vein of each person’s arm, allowing easy sampling of blood that flowed through a tube to portals in the wall. The six subjects could press buzzers for bathroom breaks, where the stool and urine were collected, but otherwise, they were alone in the near-dark. Related video
virus image with play button overlay How diseases rise and fall with the seasons—and what it could mean for coronavirus
None of these people were sick. And although the shortest day of the year was approaching, their ritual had nothing to do with pagan rites, Yuletide traditions, or the annual hippie gathering at nearby Stonehenge to celebrate the rebirth of the Sun. Instead, they were paid volunteers in a study led by infectious disease ecologist Micaela Martinez of Columbia University to investigate a phenomenon recognized 2500 years ago by Hippocrates and Thucydides: Many infectious diseases are more common during specific seasons. “It’s a very old question, but it’s not very well studied,” Martinez says.
It’s also a question that has suddenly become more pressing because of the emergence of COVID-19. With SARS-CoV-2, the virus that causes the disease, now infecting more than 135,000 around the globe, some hope it might mimic influenza and abate as summer arrives in temperate regions of the Northern Hemisphere, where about half of the world’s population lives. U.S. President Donald Trump has expressed that hope repeatedly. “There’s a theory that, in April, when it gets warm—historically, that has been able to kill the virus,” Trump said on 14 February. But what’s known about other diseases doesn’t offer much support for the idea that COVID-19 will suddenly disappear over the next few weeks. SIGN UP FOR OUR DAILY NEWSLETTER
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Different diseases have different patterns. Some peak in early or late winter, others in spring, summer, or fall. Some diseases have different seasonal peaks depending on latitude. And many have no seasonal cycle at all. So no one knows whether SARS-CoV-2 will change its behavior come spring. “I would caution over-interpreting that hypothesis,” Nancy Messonnier, the point person for COVID-19 at the U.S. Centers for Disease Control and Prevention, said at a press conference on 12 February. If the seasons do affect SARS-CoV-2, it also could defy that pattern in this first year and keep spreading, because humanity has not had a chance to build immunity to it.
Even for well-known seasonal diseases, it’s not clear why they wax and wane during the calendar year. “It’s an absolute swine of a field,” says Andrew Loudon, a chronobiologist at the University of Manchester. Investigating a hypothesis over several seasons can take 2 or 3 years. “Postdocs can only get one experiment done and it can be a career killer,” Loudon says. The field is also plagued by confounding variables. “All kinds of things are seasonal, like Christmas shopping,” says epidemiologist Scott Dowell, who heads vaccine development and surveillance at the Bill and Melinda Gates Foundation and in 2001 wrote a widely cited perspective that inspired Martinez’s current study. And it’s easy to be misled by spurious correlations, Dowell says.
Despite the obstacles, researchers are testing a multitude of theories. Many focus on the relationships between the pathogen, the environment, and human behavior. Influenza, for example, might do better in winter because of factors such as humidity, temperature, people being closer together, or changes in diets and vitamin D levels. Martinez is studying another theory, which Dowell’s paper posited but didn’t test: The human immune system may change with the seasons, becoming more resistant or more susceptible to different infections based on how much light our bodies experience.
Beyond the urgent question of what to expect with COVID-19, knowing what limits or promotes infectious diseases during particular times of year could point to new ways to prevent or treat them. Understanding seasonality could also inform disease surveillance, predictions, and the timing of vaccination campaigns. “If we knew what suppressed influenza to summertime levels, that would be a lot more effective than any of the flu vaccines we have,” Dowell says. The calendar of epidemics
At least 68 infectious diseases are seasonal, according to a 2018 paper by Micaela Martinez of Columbia University. But they’re not in sync, and seasonality varies by location. In this graphic, based on U.S. federal and state health records, each bubble represents the percentage of annual cases that occurred in each month. (The data are old because many diseases declined—in some cases to zero—after introduction of vaccines.) InfluenzaMeaslesChickenpoxPolioPertussisHepatitis AMumpsRubellaSmallpoxInfluenzaMeaslesChickenpoxPolioPertussisHepatitis AMumpsRubellaSmallpoxInfluenzaMeaslesChickenpoxPolioPertussisHepatitis AMumpsRubellaSmallpoxInfluenzaMeaslesChickenpoxPolioPertussisHepatitis AMumpsRubellaSmallpoxInfluenzaMeaslesChickenpoxPolioPertussisHepatitis AMumpsRubellaSmallpoxInfluenzaMeaslesChickenpoxPolioPertussisHepatitis AMumpsRubellaSmallpoxInfluenzaMeaslesChickenpoxPolioPertussisHepatitis AMumpsRubellaSmallpoxInfluenzaMeaslesChickenpoxPolioPertussisHepatitis AMumpsRubellaSmallpoxInfluenzaMeaslesChickenpoxPolioPertussisHepatitis AMumpsRubellaSmallpoxInfluenzaMeaslesChickenpoxPolioPertussisHepatitis AMumpsRubellaSmallpoxInfluenzaMeaslesChickenpoxPolioPertussisHepatitis AMumpsRubellaSmallpoxInfluenzaMeaslesChickenpoxPolioPertussisHepatitis AMumpsRubellaSmallpoxUnited StatesUnited StatesUnited StatesUnited StatesCalifornia California California California California United StatesUnited StatesUnited StatesUnited StatesCalifornia California California California California United StatesUnited StatesUnited StatesUnited StatesCalifornia California California California California United StatesUnited StatesUnited StatesUnited StatesCalifornia California California California California United StatesUnited StatesUnited StatesUnited StatesCalifornia California California California California United StatesUnited StatesUnited StatesUnited StatesCalifornia California California California California United StatesUnited StatesUnited StatesUnited StatesCalifornia California California California California United StatesUnited StatesUnited StatesUnited StatesCalifornia California California California California United StatesUnited StatesUnited StatesUnited StatesCalifornia California California California California United StatesUnited StatesUnited StatesUnited StatesCalifornia California California California California United StatesUnited StatesUnited StatesUnited StatesCalifornia California California California California United StatesUnited StatesUnited StatesUnited StatesCalifornia California California California California 193419331975195219451980197319711937193419331975195219451980197319711937193419331975195219451980197319711937193419331975195219451980197319711937193419331975195219451980197319711937193419331975195219451980197319711937193419331975195219451980197319711937193419331975195219451980197319711937193419331975195219451980197319711937193419331975195219451980197319711937193419331975195219451980197319711937193419331975195219451980197319711937Jan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.WinterSpringSummerAutumnMost cases in the year (GRAPHIC) N. Desai/Science; (INTERACTIVE) X. Liu/Science; (DATA) Project Tycho
Martinez became interested in seasonality when, as an undergraduate at the University of Alaska Southeast, she had a job tagging Arctic ringed seals, doing skin biopsies and tracking their daily and seasonal movements. While working on her Ph.D., her focus on seasonality shifted to polio, a much-feared summer disease before the advent of vaccines. (Outbreaks often led to the closing of swimming pools, which had virtually nothing to do with viral spread.) Polio seasonality in turn made her curious about other diseases. In 2018, she published “The calendar of epidemics” in PLOS Pathogens, which included a catalog of 68 diseases and their peculiar cycles.
Except in the equatorial regions, respiratory syncytial virus (RSV) is a winter disease, Martinez wrote, but chickenpox favors the spring. Rotavirus peaks in December or January in the U.S. Southwest, but in April and May in the Northeast. Genital herpes surges all over the country in the spring and summer, whereas tetanus favors midsummer; gonorrhea takes off in the summer and fall, and pertussis has a higher incidence from June through October. Syphilis does well in winter in China, but typhoid fever spikes there in July. Hepatitis C peaks in winter in India but in spring or summer in Egypt, China, and Mexico. Dry seasons are linked to Guinea worm disease and Lassa fever in Nigeria and hepatitis A in Brazil.
Seasonality is easiest to understand for diseases spread by insects that thrive during rainy seasons, such as African sleeping sickness, chikungunya, dengue, and river blindness. For most other infections, there’s little rhyme or reason to the timing. “What’s really amazing to me is that you can find a virus that peaks in almost every month of the year in the same environment in the same location,” says Neal Nathanson, an emeritus virologist at the University of Pennsylvania Perelman School of Medicine. “That’s really crazy if you think about it.” To Nathanson, this variation suggests human activity—such as children returning to school or people huddling indoors in cold weather—doesn’t drive seasonality. “Most viruses get transmitted between kids, and under those circumstances, you’d expect most of the viruses to be in sync,” he says.
Nathanson suspects that, at least for viruses, their viability outside the human body is more important. The genetic material of some viruses is packaged not only in a capsid protein, but also in a membrane called an envelope, which is typically made of lipids. It interacts with host cells during the infection process and helps dodge immune attacks. Viruses with envelopes are more fragile and vulnerable to adverse conditions, Nathanson says, including, for example, summertime heat and dryness.
A 2018 study in Scientific Reports supports the idea. Virologist Sandeep Ramalingam at the University of Edinburgh and his colleagues analyzed the presence and seasonality of nine viruses—some enveloped, some not—in more than 36,000 respiratory samples taken over 6.5 years from people who sought medical care in their region. “Enveloped viruses have a very, very definite seasonality,” Ramalingam says.
In a study in New York and New Jersey, Micaela Martinez hopes to find out how artificial lighting affects the immune system. Mike Grippi
RSV and human metapneumovirus both have an envelope, like the flu, and peak during the winter months. None of the three are present for more than one-third of the year. Rhinoviruses, the best-known cause of the common cold, lack an envelope and—ironically—have no particular affinity for cold weather: The study found them in respiratory samples on 84.7% of the days of the year and showed that they peak when children return to school from summer and spring holidays. Adenoviruses, another set of cold viruses, also lack an envelope and had a similar pattern, circulating over half the year.
Ramalingam’s team also studied the relationship between viral abundance and daily weather changes. Influenza and RSV both did best when the change in relative humidity over a 24-hour period was lower than the average (a 25% difference). “There’s something about the lipid envelope that’s more fragile” when the humidity changes sharply, Ramalingam concludes.
Jeffrey Shaman, a climate geophysicist at Columbia, contends that what matters most is absolute humidity—the total amount of water vapor in a given volume of air—and not relative humidity, which measures how close the air is to saturation. In a 2010 paper in PLOS Biology, Shaman and epidemiologist Marc Lipsitch of the Harvard T.H. Chan School of Public Health reported that drops in absolute humidity better explained the onset of influenza epidemics in the continental United States than relative humidity or temperature. And absolute humidity drops sharply in winter, because cold air holds less water vapor.
Why lower absolute humidity might favor some viruses remains unclear, however. Variables that could affect the viability of the viral membrane could include changes in osmotic pressure, evaporation rates, and pH, Shaman says. “Once you get down to the brass tacks of it, we don’t have an answer.”
Will SARS-CoV-2, which has an envelope, prove fragile in spring and summer, when absolute and relative humidity climb? The most notorious of the other coronavirus diseases, SARS and Middle East respiratory syndrome (MERS), offer no clues. SARS emerged in late 2002 and was driven out of the human population in the summer of 2003 through intensive containment efforts. MERS sporadically jumps from camels to humans and has caused outbreaks in hospitals, but never widespread human-to-human transmission like COVID-19. Neither virus circulated for long enough, on a wide enough scale, for any seasonal cycle to emerge.
If we knew what suppressed influenza to summertime levels, that would be a lot more effective than any of the flu vaccines we have. Scott Dowell, Bill and Melinda Gates Foundation
Four human coronaviruses that cause colds and other respiratory diseases are more revealing. Three have “marked winter seasonality,”
That does not mean COVID-19 will as well. The virus can clearly transmit in warm, humid climates: Singapore has more than 175 cases. Two new papers published on preprint servers this week come to opposite conclusions. One, co-authored by Lipsitch, looked at COVID-19 spread in 19 provinces across China, which ranged from cold and dry to tropical, and found sustained transmission everywhere. The second study concludes that sustained transmission appears to occur only in specific bands of the globe that have temperatures between 5°C and 11°C and 47% to 70% relative humidity...
Animal studies support the idea that immunity changes with the seasons.
I think your keyboard has virus
Air temperature and humidity are major factors as well. Most viruses won’t last more than a few minutes under the summer sun.
LoL. I know what you are referring to, and it's not the temperature and or humidity, but you see I had immigrated html for the image but when I previewed its effects and realized what a mess it would be, then I went back and quarantined it in order to wipe it out.
However, when I posted the article it was still there! Which means that the rapidity of its replication is amazing. You though you had it wiped out, and yet it must have made a copy of itself. Which could mean that it is now going viral! Today FR servers , and tomorrow the world!
Pardon me while I contact the Centers for Digit Control and the World Holograph Organization and alert them. Meanwhile cover your monitor and wash your keyboard.
The CCP virus hysteria will someday be known as the most egregious hoax in history.
The CCP virus hysteria will someday be known as the most egregious hoax in history.
Tell it to the victims
The CCP virus hysteria will someday be known as the most egregious hoax in history.
You are correct. people are dying from it. but, people will die with the current shutdown as well.
It’s rational to believe that this bug will fade out like every other respratory virus has prevously.
The background noise of death. It trundles on day after day, year after year. Generally without the media rubbing you nose in it.
Author writes "...artificial light may play havoc with the circadian rhythms that have evolved, with unpredictable effects on disease susceptibility." I would speculate that invention of electric light reduced the amount of sleep people get, especially in winter, and sleep has been shown in many studies to be extremely important to immune system performance and response.
In the past 20 years (particularly in the past 10 since the iPhone and iPad were invented), we have the advent of LED and OLED screens and a huge growth of screen time. These are known to negatively impact the quantity and quality of sleep.
Dr. Seheult on the MedCram COVID series has two or three sessions dedicated to the effect sleep has on the immune system. He is a big believer in the therapeutic effect of sleep and improvement of immune system performance as a result of getting more sleep.
I think your keyboard has virus
_______________________________________________________________
Bill Gates is on it now, standby.
Yes.
We are all going to die.
Let’s hope it later rather than sooner.
I do not understand: I just received the latest vaccination yesterday.
80,000 Americans died of the flu the winter of 2017-2018.
Why weren’t you there to protect them, you virtue-signalling imbecile?
I think back to when my grandpa was born in 1925 when diseases like malaria, small pox, typhoid fever, cholera, and TB were endemic to the US. People did not live in a constant state of fear and this was before there was mechanical ventilation, or antibiotics.
Explain it to the victims
Tin off your tin foil hat for a moment and have some compassion for the victims.
This isn’t a hoax, just like 911 wasn’t a hoax or sandy hook wasn’t a hoax
Do you think President Trump is lying to us? If so, why should we re-elect him? I am all ears
Jet travel wasn’t prevalent back then either, cities were spread out farther, took a while to travel from place to place.
The world is smaller today because of our transportation technology. So disease can spread faster.
President Trump stop travel from China, and saved California and he was called a racist for doing that.
Now all of those diseases have cures or vaccines so they are no longer a big deal.
It’s doubtful that the shutdown saved many lives.
Thousands maybe, and thousands died anyway.
What is certain is the MILLIONS will die world-wide from the economic catastrophe idiots like you applaud.
The only tinfoil I see around here is shoved up your...
Just curious, but all we hear about is the CCP virus from Wuhan which is now in remission there.
BUT, is there any word about Bejing or Shanghai deaths due to the virus?
No point in responding to someone so irrational and operating on feelings.
The personal attacks on you and name calling show exactly what he has to work with to support his contention about the bad economy killing more people than the virus.
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