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August 7, 2020

Weekly line: How to make the indoors safer from the new coronavirus

Daily Briefing

    Earlier this week, Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, reiterated a warning  public health experts have been issuing since the beginning of America's coronavirus epidemic: If the United States doesn't get transmission of the virus under control by the time colder weather arrives, the country could see yet another dangerous peak in new cases.

    The 'recurring themes' of disease outbreaks

    Now, you might be thinking, "What does weather have to do with the coronavirus' transmission?" As it turns out, a whole lot.

    Colder weather and the coronavirus could be a 'recipe for disaster'

    Much of the answer centers around how people typically behave in colder weather. While many of us tend to spend our time outside in the warmth and sun during summer months, we tend to shelter indoors when it's blustery and cold outside.


    As Ashish Jha, director of the Harvard Global Health Institute, recently told The Atlantic's Joe Pinsker, "There really is no easy way to socialize during late fall [and] winter in large parts of the country if you're not doing it outside."

    And therein lies the crux of the issue: Evidence has shown that many viruses, including the novel coronavirus, spread much easier indoors. That's largely because people usually are closer together when indoors, and because indoor ventilation, heating, and cooling systems recycle and move around germ-filled air that can transmit pathogens to from one person to a whole room of people. Further, heated indoor air during cold months tends to be dry, which is a more favorable environment for the coronavirus, Linsey Marr, a civil and environmental engineering professor at Virginia Tech, explained to Pinsker.

    Under those circumstances, it would be difficult to control the coronavirus' transmission.

    "Could I have people over in my house for two hours on a Sunday morning in December? Barring really good testing, probably not," Jha told Pinsker. (And as Jha has noted separately, America's coronavirus testing system currently falls woefully short.) He added, "We know that the biggest risk of spread for this virus is when meaningful numbers of people gather indoors for any extended period of time."

    And the situation could be especially fraught if people don't wear face masks or coverings while indoors, public health experts say. As Jha told Pinsker, "People are already feeling pandemic fatigue, and … that'll only get worse."

    Andrew Noymer, a public health professor at UC-Irvine, added, "People are going to want to go to bowling alleys and whatnot, and that's a recipe for disaster, honestly—particularly if they don't want to wear masks."

    But while it can seem that America's on a collision course with a cold-weather spike in new coronavirus cases—especially as the country already is grappling with new peaks in infections and morbidity—we may not be completely doomed. Some businesses have been looking into new technologies they can use to make the indoors safer—and there are steps individuals can take, as well, to help protect themselves against contracting the coronavirus while indoors.

    Businesses turn to new technologies to make their buildings safer

    For example, one business, Magnolia Bakery, planned to install "cleansing chamber[s], analogous to the disinfecting airlocks outside biohazard labs," at its New York City locations, writes Christopher Mims in the Wall Street Journal. Anyone entering the locations would have to walk through the chambers, which "bath[e]" their "entire bodies … in ultraviolet light for 20 seconds," according to Mims. He explains, "Based on years of research, scientists say they are confident this particular type of UV light is lethal for viruses and bacteria, but safe for humans."

    Other businesses are looking to improve indoor air quality by installing filters in their ventilation systems that can "catc[h] even the finest particles, including ones as small as the coronavirus, so that air ducts aren't spraying a fine mist of recirculated, potentially virus-laden droplets all over everyone who walks by," Mims writes. For example, airplanes and hospitals typically are equipped with such filters, often using high-grade HEPA filters that fully and frequently filter the air.

    William Bahnfleth—who heads the Epidemic Task Force at the American Society of Heating, Refrigerating and Air-Conditioning Engineers—told Mims it's unlikely most businesses would implement air filters that meet the standards of airplanes and hospitals, but Mims writes that they could turn to other technologies—such as ionizing filtration systems and high-frequency ultraviolet light, known as UVC light—to filter their air.

    Meanwhile, some companies are using software to track employees' health and contacts and to generate workspace plans that encourage physical distancing to make their indoor spaces safer, the New York Times' Natasha Singer and Julie Creswell report.

    However, as Laura Becker, a research manager who focuses on employee experience at I.D.C., told Singer and Creswell, "These are all untested theories and methods right now."

    And as Mims notes, "[e]xperts emphasize that the best approach to reducing illness in shared spaces is to employ many different interventions, not just one magical air filter or light fixture."

    What you can do to protect yourself against the coronavirus indoors?

    Therefore, experts say much of what you've already been doing to protect yourself against the new coronavirus will still apply—and even more so—when cold weather forces us back indoors.

    If you must meet people indoors, experts say you'll want to be careful to stay at least six feet away from others, wear a face mask or covering, and disinfect high-touch surfaces. You also should try to meet in a building that isn't crowded and that has adequate filters in its ventilation system—as well as substantial ventilation overall. Open windows and doors if you can, and it wouldn't hurt to use a portable humidifier and air purifier, experts say. In addition, try to limit the amount of time you spend with others indoors, if possible.

    Getting a flu shot also could help, some experts say. The United Kingdom's Academy of Medical Science in a report notes that contracting the flu could cause a person to cough or sneeze more frequently—activities that release droplets and aerosols that can spread the coronavirus and other pathogens.

    But overall, the best thing you can do to protect yourself while indoors is to avoid being indoors at all with individuals who don't live in your household, experts say. As Pinsker notes, if all of the amount and types of precautions you need to take to protect yourself while indoors "soun[d] onerous, it's because spending time indoors with people you don't live with is really risky—and better avoided if you can help it."

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