The items below are highlights from the free newsletter, “Smart, useful, science stuff about COVID-19.” To receive newsletter issues daily in your inbox, sign up here:

This 10/28/20 story in El País, by Mariano Zafra and Javier Salas, features excellent visuals that illustrate the airborne risk of SARS-CoV-2 infection for a set number of people in indoor settings for several hours under various additive conditions, including: a) no protective measures, b) people consistently wear masks, c) masks are worn, the premises are ventilated, and people spend fewer hours in the setting. The settings include a living room, a bar or restaurant, and a school classroom. The illustrations rely on calculations yielded by a tool developed by atmospheric chemist Jose-Luis Jimenez of the University of Colorado Boulder, and colleagues.

A lot of us are facing difficult decisions these days about traveling and gathering for holidays. “Staying home is the best way to protect yourself and others” from SARS-CoV-2, according to the introduction to a helpful interactive on travel safety published at The Washington Post (10/5/20). For each of five questions on topics such as lodging, mode of travel or travel companions, the interactive returns a summary of the associated virus-transmission risk, travel safety tips, testing advice, and preventive measures you can or should take, such as quarantining, mask-wearing, hand-washing, social distancing, and advance discussions.

Clever headline on this 10/23/20 Kaiser Health News story: “Travel on Thanksgiving? Pass the COVID.” The piece by Anna Almendrala rounds up lots of helpful advice: 1) ideally, don’t travel and don’t widen your social circles for the holiday, the story states; 2) if you travel locally to dine with others, interact only with people in your household, aka self-quarantine, for two weeks before the event to minimize risk (this is only feasible for people who do not work outside the home and people without children attending school in-person; your housemates must also self-quarantine for this to be effective); 3) California’s Department of Public Health issued these “harm-reduction” guidelines for people who do attend holiday gatherings; 4) if you fly, “get tested before the flight for peace of mind, buy tickets on a plane that is leaving middle seats empty, use highly protective N95 masks and possibly face shields, and blast the individual airplane vents directly onto each family member to disrupt potential virus particles. And, of course, wash your hands frequently.”

For the Washington Post, Natalie B. Compton stayed at a budget, mid-range, and upscale hotels to assess their SARS-CoV-2 prevention measures (10/13/20). The story suggests that you’re as safe at a budget hotel as you are at a mid-range hotel, but there is no safety advantage to staying in an expensive “luxury” hotel. Relevant measures at a Holiday Inn Express included automatic doors to the main entrance, social distancing stickers on the lobby floor, plexiglass panels to separate guests and desk workers, and to-go breakfast bags. At a Hyatt, Compton found a hand sanitizer dispenser in the lobby, plexiglass dividers at the check-in desk, contact-less check-in, extra disinfection of rooms, and a gym available by appointment.

If you haven’t yet devised or purchased a portable air cleaner for your home, school, or workplace, here’s an advice essay on the topic, by freelance writer Laura Daily for The Washington Post (10/19/20). Two well-respected public health researchers who focus on indoor air both recommend placing portable air cleaners with HEPA (high-efficiency particulate air) filters in school classrooms, Daily writes. Know the area of the room where you wish to install a filter, and then check the device’s specifications to ensure that it can handle the job. The piece links to a site created by researchers at the Harvard School of Public Health and University of Colorado, Boulder that can be used to select an appropriate air filter for a room of specific dimensions. Air cleaners at home are likely worth considering only if you live with someone whose job or school puts them in contact with others, the piece suggests. Air purifiers do not eliminate the risk of indoor transmission, so continue to wear a mask, wash hands and distance if guests visit, the story describes the experts as advising.

At Wired, Gregory Barber revisits the weak, indirect evidence that touching recently infected surfaces and then our face is a significant way that SARS-CoV-2 spreads (10/20/20). Nearly all cases of transmission now have been linked to “shared air,” although transmission from surfaces (known in infectious disease research as “fomites”) cannot be entirely ruled out, he reports. Early evidence on the persistence of the virus on surfaces led to “the great fomite freakout” this spring, according to a Princeton University mathematical biologist who is quoted in the story and coauthored the early surface-persistence research. Yes, SARS-CoV-2 can persist on some hard surfaces for hours or days, but these data say nothing about one’s personal risk for infection, the dose of viral particles transferred, the likelihood of particles entering your airway and infecting you, and other real-life (not laboratory) conditions like humidity, temperature, and light levels, the story states. Hospitals should still wipe down high-touch objects, and people at high-risk for COVID-19 “may want to take extra precautions,” Barber writes. At this point, many people and organizations remain needlessly fixated on obsessively wiping down school, church, library, public transit and household surfaces, the story suggests. “Worrying about the small stuff exhausts people from focusing on things that do matter,” Barber writes.

A 10/14/20 guide to forming a pandemic pod with close friends and/or families to help make the U.S. winter more bearable offers the following advice: 1) form a pod only with people who share your level of risk tolerance and exposure control practices; 2) keep the size of your pod as small as five to 10 people; 3) create a pact of rules and standards, possibly in writing, for all pod members; and 4) make a response plan ahead of time in case a pod member tests positive for SARS-CoV-2. By Allyson Chiu at The Washington Post.

Check out this thought-provoking examination by Sam Bloch at The Counter of claims that individuals with unhealthy diets are more vulnerable to COVID-19 (10/15/20). It’s a complicated issue. Sure, a less healthy diet is linked to obesity, diabetes, heart disease, and high blood pressure, and those risk factors put one at higher risk for severe COVID-19. However, that does not explain why the incidence of COVID-19 is higher in the U.S. than it is in other countries with similar obesity rates, suggests a University of North Carolina at Chapel Hill nutrition researcher. And the risk of dying from COVID-19 is higher among black and Latino populations, irrespective of obesity, points out a Harvard School of Public Health policy researcher. Assertions that people choose healthy or unhealthy diets are on shaky ground, in part because healthier foods (fruits, vegetables, lean meats) cost more than calorie-dense, nutrient-poor foods such as soda pop and corn-derived snacks. Plus: “If people were becoming irresponsible, you’d expect to see it in areas other than food,” the director of the World Food Policy Center at Duke University is quoted as saying. “But if you look at other health-related behaviors—like, do people brush and floss, do they wear seatbelts, or do they get preventive medical exams—over time, the rates of those things has improved or stayed the same.”

An inexpensive, over-the-counter drug often used as a treatment against parasitic worms is in high demand in Perú, Bolivia, Guatemala and other parts of Latin America as an unproven preventative for COVID-19, reports freelance science journalist Emiliano Rodríguez Mega for Nature (10/20/20). Little evidence suggests that the drug, called ivermectin, is effective, the story states. Now, the popularity of the drug makes it difficult for COVID-19 researchers to find potential study subjects who have not already taken it, Rodríguez Mega reports. The drug has been linked to tremors, convulsions, lethargy, and disorientation, as well as brain damage and comas in people with a certain genetic mutation, Rodríguez Mega writes. A global health researcher at Cayetano Heredia University in Perú is quoted as saying: “What we’re having is a populist treatment, instead of an evidence-based treatment.” Some researchers continue to try to recruit patients for small-scale or ongoing studies of the drug’s possible effectiveness against COVID-19, the story states.

Science magazine's Dance Your PhD competition is on, now with an additional COVID-19 category. The submission deadline is 1/29/21 (Science, 10/26/20).