You know how to stay 100 percent safe from the coronavirus: total isolation. Stay in lockdown, work from home, physically interact with no one. But there’s only so long you can live like that. Eventually, you have to start coming out into the world. And while doing so is certain to increase your chance of getting sick, an informed risk-mitigation strategy can help you keep the danger to yourself and others quite low.
A relatively safe strategy for exiting lockdown can be boiled down to a few basic principles: stay outdoors; wear a mask; stick to small groups; try to avoid passing around objects; wash your hands.
Here are some activities at the safer end of the spectrum as you exit lockdown, along with some data-based guidance on how best to minimize the risks of transmission:
Go to the Beach
There’s been a lot of outrage expressed over photos of people jammed into parks and beaches, but meeting outdoors seems to be one of the safest ways to interact with real people. One recent study of 318 outbreaks in China found that only one occurred in an outdoor environment.
The environmental conditions found on a beach in summertime serve as a natural line of defense against COVID-19. A fresh ocean breeze can disperse the droplets of moisture that are expelled when an infected person coughs, sneezes, talks, or even just breathes. High humidity and temperature have been shown to slow transmission of the virus. And the UV radiation in sunlight kills a wide variety of pathogens on surfaces. (It’s absolutely false, however, to think that beaming UV light into the body would be effective, as President Trump has speculated.)
Stroll With a Friend
The act of speaking can produce thousands of droplets of moisture per minute, so conversation with a potentially infected person is inherently dangerous. You can reduce your risk by staying six feet apart and wearing masks. Even homemade masks that filter out two-thirds of droplets can be effective in shutting down transmission. A computer-simulation project, led by De Kai of the Hong Kong University of Science and Technology, found that if 80 percent of people wear partially effective masks, the spread of the virus will be contained.
There’s nothing magical about six feet, by the way. In laboratory studies, sneezes have been found to carry droplets more than 20 feet. But the largest, heaviest droplets that carry the most virus particles will tend to settle within a much shorter distance. So six feet is a reasonable compromise between safety and effort.
Go Jogging or Biking
There’s no evidence linking biking or jogging to COVID-19 transmission. Wind tunnel tests in the Netherlands suggest that a person running without a mask creates a wake of droplets that can extend several yards, so for maximum safety, it’s best to avoid being directly behind someone who’s biking or jogging. But as a practical matter, such ephemeral proximity likely poses little risk. The CDC’s guidelines state that the virus is mostly transmitted between people who are in close contact with a carrier for more than 15 minutes.
Sports that can be played at a good remove from one’s opponent are ideal for COVID-era fitness, but they share one risk factor: They involve frequent touching of an exchanged object. Another major route for infection is through what are called fomites, or surfaces that may be contaminated with the virus. If an infected person coughs into his hand, then picks up a ball and throws it to you, and you catch it and then touch your face, you could be infecting yourself with thousands of virus particles.
During the early days of the pandemic, a widely circulated piece of advice was to wear gloves at all times, but that view has since gone by the wayside, since gloves tend to give people a false sense of security and offer little actual protection if worn incorrectly. Instead, experts now recommend practicing “hand hygiene.” Assume that everything you touch is contaminated. If you touch a virus-laden surface followed by your phone, your phone is then contaminated. And so is the pocket you put it into. And so on. So don’t touch surfaces if you don’t have to, and wash your hands as soon as you can. (Hand sanitizer is less effective than washing, but better than nothing.)
One trick for avoiding contamination while playing tennis is to use twice as many balls as usual. The United States Tennis Association suggests that each player bring their own can, and return their opponents’ balls either by kicking them or scooping them with their racket. The USTA also suggests that players not switch sides between games.
Meet Friends at an Outdoor Cafe
Many of us are starved for interaction after months of lockdown, but trying to restore our social lives all at once is risky. The more people you hang out with, the greater the chance one of them will be shedding the virus. And the danger rises exponentially. If 2 percent of people are active cases, then in a gathering of ten people, there’s a one-in-five chance that one of them will have it. (A recent study in Indiana found that 1.7 percent of randomly selected subjects had an active infection.) In a gathering of 35, the odds are 50-50.
Moving into an indoor space occupied by other human beings inherently increases the risk of catching COVID-19. Instead of being dispersed by the wind, tiny particles remain suspended. Researchers who used lasers to identify the droplets produced by people speaking found that droplets hung in the air for more than eight minutes.
The artificial circulation of air produced by fans or air-conditioning can improve matters, but it can also make them worse. One super-spreader event in China occurred when an infected customer sitting at a table in the middle of a small restaurant spread COVID-19 to five diners sitting at two other tables that lay within the flow of the restaurant’s air-conditioning system, while diners sitting outside that flow were unaffected.
Reducing restaurant capacity by half will improve diners’ odds, but the safest bet if you’re going to eat at a restaurant is to find one with outdoor seating. Keep an eye out for how well staff are following the rules: They should be wearing masks, discarding paper menus, and other disposable items between seatings, and disinfecting tables and other surfaces.
Go on a Date
Swapping body fluids is obviously a great way to pass along a communicable disease. But if you connect with someone online and are careful when you meet them in person, then by the logic of the math above, the odds that they’re infected will actually be quite low — especially if your precontact courtship lasts a little while, they’ve otherwise exercised careful social distancing, and they don’t have any symptoms.
Take a Flight (But Only If You Must)
A crowded space where a large number of strangers are forced together for prolonged periods of time: an airplane cabin ticks off all the boxes of a likely place to catch an infectious respiratory disease. Indeed, in 2003 a single infected passenger infected 22 others aboard an Air China flight with the SARS coronavirus; five of those who were infected died. So far, no such super-spreader events have taken place on planes with COVID-19, but the risk is real. More important, air travel is a major vector by which disease is spread from one geographical area to another. America’s first known patient was a man who had just traveled to the U.S. from Wuhan.
If you do need to travel by air, verify that your airline is following safety protocols. While JetBlue is refusing to board passengers who aren’t wearing a face mask, for instance, Southwest Airlines is reportedly not enforcing that rule. During the early phase of the pandemic, when few people were flying, airlines were able to space passengers out by leaving middle seats empty. But flights are getting a little more crowded now. Before booking a flight, check a carrier’s policies. Delta and Spirit are two of the few airlines promising to keep middle seats empty.
Of course, there are no magical solutions, and while you can mitigate risk, you can’t eliminate it. Joseph Fair, a virologist who worked on the Ebola outbreak and many others, tweeted on May 13 that he had come down with a severe case of COVID-19, despite having “used max precautions.” Fair suspects he became infected during an airplane flight during which he wore a mask and gloves and used hand wipes. He noted that the airline did not enforce social distancing. “Nobody is immune!” he cautioned. “Not even a virus hunter.”