Few people remember Dr. Charles Chapin, which is just as well because he’s most famous for getting something not quite right. It was Chapin, an American public health researcher, who in 1910 published the book The Sources and Modes of Infection, in which he sought to disabuse readers of the theory of “miasmas,” clouds of disease that linger in the air and can infect anyone luckless enough to cross their path. He was right to reassure readers that foul smells alone can’t cause disease, but then he went a bit too far.
“It will be a great relief to most persons to be freed from the specter of infected air, a specter that has pursued the race since the time of Hippocrates,” Chapin wrote.
A great relief indeed, though in some cases infected air does exist, only today we call it aerosols. These tiny particles linger in the air for minutes or even hours and can indeed be a leading cause of disease. As Jose-Luis Jimenez, a professor of chemistry at the University of Colorado-Boulder writes in TIME today, it’s important to acknowledge the role aerosols play in the spread of COVID-19, and to sound an alarm that, he and others fear, is not being heeded.
Though the World Health Organization (WHO) and the U.S. Centers for Disease Control and Prevention agree that aerosols—emitted when we cough, sneeze, shout, sing or even speak—can be a vector for coronavirus transmission, they see it as a marginal one. The greater risks, they argue, are posed by fomites—objects, including skin, that can be contaminated with virus—and droplets, drops of saliva or mucus, much larger than aerosol particles, that are also emitted by coughing, speaking and more. But on July 6, Jimenez and 239 other scientists appealed to the WHO to change its position and give aerosols the attention they deserve.
Jimenez’s arguments are manifold. For one thing, he questions the significance of fomite transmission, acknowledging that it decidedly happens, but notes that the virus does not remain viable on the hands long, which means that it would be necessary to touch the mouth, eyes or other mucus membrane quickly to contract the virus. That happens of course, but not enough to explain the exceedingly high transmissibility of the novel coronavirus.
Droplets, similarly, are limited in their danger because their relatively heavy weight means they move ballistically, exiting the mouth and remaining airborne for distances of only three to six feet. “They fly like a cannonball from someone’s mouth and then travel through the air until they either hit something (worst case someone else’s eyes, mouth or nostrils) or fall to the ground,” Jimenez writes.
Aerosols, on the other hand, are the kind of trouble that can linger—mostly because they are so light and small. A human hair measures about 80 microns in diameter; an aerosol droplet is just 50. And as for SARS-CoV-2, the virus that causes COVID-19? Just 0.1 microns, meaning that an awful lot of it can fit inside a single aerosol droplet.
The best analogy for an aerosol, Jimenez says, is cigarette smoke. Yes, you get more second-hand smoke if you’re standing near the person who is the source of it, but over time it builds up in the air, especially indoors in poorly ventilated rooms—meaning even if you’re far away from the smoker, you’ll breathe in the smoke. Now imagine every particle of secondhand smoke carried a potentially deadly viral payload.
That’s the warning Jimenez is sounding, and he’s hoping that health authorities heed it. “In a fast-moving viral pandemic, scientific understanding will inevitably change as research catches up to the speed at which the virus spreads,” he writes. “However, it seems clear that aerosols are more important when it comes to transmitting COVID-19 than we thought six months ago—and certainly more important than public health officials are currently making them out to be.”
More than 23.6 million people around the world had been sickened by COVID-19 as of 1 a.m. eastern time today, and more than 813,000 people have died. Here's where daily cases have risen or fallen over the last 14 days, shown in confirmed cases per 100,000 residents:
On August 24, there were nearly 227,000 new cases and 4,346 new deaths confirmed globally. Here's how the world as a whole is currently trending:
Here is every country with over 300,000 confirmed cases:
Mexico, with more than 563,000 cases of COVID-19 trails only six other countries in overall case count, and the government has already determined that it will not be safe for the country’s 30 million students to return to school this year. That means remote learning—and that, in turn, presents a problem. Only 56% of households have access to the Internet. What 93% of households do have, however, is a TV. That, as CNN reports , suggests an obvious solution: scrap some programming and replace it with broadcast classes. In a comprehensive agreement with multiple Mexican channels, a full curriculum of pre-K through 12 classes will be recorded and broadcast 24 hours a day, making them accessible to students regardless of household schedules.
There’s no country in Europe that needs a second COVID-19 lockdown more than Spain. After adding more than 78,000 cases in the past two weeks, the country now has had 166 cases per 100,000 residents, compared to France’s 67 and the U.K.’s 22. As The Guardian reports , this has the Prime Minister Pedro Sánchez considering at least regional lockdowns in areas where the infection rate is the highest. But the business community is pushing back. The country is suffering one of its deepest recessions in memory as a result of the first lockdown, and psychologists are warning of the consequences of another lockdown, pointing to one study in Spain and Italy showing that 86% of parents report a change in their children’s emotional state as a result of quarantining.
On the same day Africa celebrated after the World Health Organization officially declared it polio-free, there is bad news for the continent on another health front. The World Bank Blog reports that the mandatory shutdowns and quarantines that are part of a continent-wide strategy to combat COVID-19 are having some predictable but unavoidable consequences. More than 71 million people, the Bank estimates, could be pushed into extreme poverty as business grinds to a halt. A third of that total live in Sub-Saharan Africa, which was already battling its worst recession since 1995. Partly to combat that, African leaders have issued a global appeal for funding assistance, deferral of debt payments and assistance in procuring medical supplies. They are racing to fortify hospitals and other health care centers with supplies and personnel to handle a potential crush of patients when COVID-related restrictions are finally eased.
The Situation in the U.S.
The U.S. had recorded more than 5.7 million coronavirus cases as of 1 a.m. PM eastern time today. More than 177,000 have died. Here's where daily cases have risen or fallen over the last 14 days, shown in confirmed cases per 100,000 residents:
On August 24, there were more than 38,000 new cases and 450 new deaths confirmed in the U.S. Here's how the country as a whole is currently trending:
A switch of just two letters in the 30,000-character genetic code of COVID-19 has helped epidemiological sleuths pinpoint a super-spreader event in Boston, reports The Washington Post in a sort of medical whodunit story. The event, ironically, was a gathering of executives from the biotech company Biogen, at a Boston hotel from Feb. 25 to 27. Within two weeks, at least 35 attendees had fallen ill. Within two months, the telltale strain of the virus had reached two Boston homeless shelters, sickening 122 people. A new (yet-to-be peer reviewed) study published on the medical preprint website medRxiv, compared the single strain to 800 others and found that it had spread to Alaska, Senegal and Luxembourg, as well as accounting for about a third of all cases sequenced in the state of Massachusetts and 3% of all those in the U.S. as a whole.
According to an analysis published by The New York Times, experts generally believe that the U.S. Food and Drug Administration (FDA) “grossly misrepresented” the effectiveness of convalescent plasma in treating COVID-19 at the Aug. 23 press conference, during which the agency granted emergency use authorization to the procedure. The key number at the center of the outcry is the FDA’s assurance that the use of convalescent plasma could reduce COVID-19 deaths by 35%. But that number, critics claim, was drawn from one small sub-group of patients at the Mayo Clinic who were under 80 years old and were not dependent on ventilators. What’s more, they received particularly robust plasma that was known to be high in antibodies and received it early—within three days of falling ill. That ideal set of circumstances would be hard to replicate on a broad scale.
The FDA’s possible overstatement could have another unintended effect, reports The Sacramento Bee: It could effectively sabotage double-blind studies to determine the actual effectiveness of the treatment. Those kinds of studies require two sample groups of volunteers: one receiving an actual treatment and one receiving a placebo. But if the public is led to believe that plasma is a proven treatment, the pool of potential placebo volunteers dries up.
Just as public health officials warned, the motorcycle rally held in Sturgis, N.D. which ended on Aug. 16 appears to have been a fertile petri dish for COVID-19. The AP reports that so far health officials in South Dakota, Minnesota, Nebraska and Wyoming, have confirmed 81 cases among people who attended the nine-day event. Those numbers have spooked epidemiologists, who point to cell phone data showing that 61% of all counties in the U.S. have been visited by at least one person who was in Sturgis for the rally. South Dakota governor Kristi Noem has defended holding the event—not least because of the $800 million in annual tourist revenue it has generated in previous years.
All numbers unless otherwise specified are from the Johns Hopkins University Center for Systems Science and Engineering, and are accurate as of August 25, 1 a.m. eastern time. To see larger, interactive versions of these maps and charts, click here.
WHAT ELSE YOU SHOULD KNOW
Hero or Villain?
You’d think that Professor Zhang Yongzhen, the scientist in China who first sequenced the SARS-CoV-2 genome would be nothing short of a hero. But a six-day delay in publishing the results combined with American finger-pointing at the so-called “China virus” have meant nothing but headaches and controversies for Zhang. In an exclusive, he tells his story to TIME. Read more here.
COVID-19 at the Ballot Box
With Texas increasingly trending purple, a cluster of hotly contested Congressional districts also happen to be areas particularly hard-hit by the state’s coronavirus resurgence. As Politico reports, Republican incumbents are defending President Trump’s handling of the pandemic while Democratic challengers are hammering them hard for what they claim is overall GOP fecklessness. Read more here.
No Deep State at FDA
Dr. Stephen Hain, the head of the FDA, may tread lightly when it comes to disputing President Trump’s often-untrue statements about COVID-19. But he draws the line at Trump’s baseless charge that “deep state” elements at the agency are delaying approval of a coronavirus vaccine to thwart the president’s reelection chances. “I have not seen anything that I would consider to be ‘deep state’ at the FDA,” Hahn told Reuters. Read more here.
Four Ways to Resist Coronavirus
Not all immunities to coronavirus will be created equal—indeed they come in four varieties: sterilizing immunity, functional immunity, waning immunity and lost immunity. As STAT News reports, any or all could help us learn to live with the coronavirus threat. Read more here.
Historic Echoes in Today’s Dilemmas About Reopening Schools
This isn’t the first time American parents have been afraid to send their children back to school in the fall. Before the Salk vaccine was approved in 1955, polio was a summertime scourge that sometimes leaked into September. The threat of children contracting COVID-19 in school is scary enough; the threat of their contracting a paralytic disease was far worse. Read more here.
Thanks for reading. We hope you find the Coronavirus Brief newsletter to be a helpful tool to navigate this very complex situation, and welcome feedback at coronavirus.brief@time.com.
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Today's newsletter was written by Jeffrey Kluger and edited by Elijah Wolfson.
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