Here are four concepts from other harm-reduction strategies that can help to guide our decisions:
Relative risk. Driving is an activity that carries risk, which can be reduced by following the speed limit and wearing a seat belt. For covid-19, we can think of risk through three key variables: proximity, activity and time. The highest-risk scenario is if you are in close proximity with someone who is infected, in an indoor space, for an extended period of time. That’s why when one person in the household becomes ill, others are likely to get infected, too. Also, certain activities, such as singing, expel more droplets; in one case, a single infected person in choir practice spread covid-19 to 52 people, two of whom died. The same goes for gatherings where people hug one another — funerals and birthdays can be such “superspreader” events. Conversely, there are no documented cases of someone acquiring covid-19 by passing a stranger while walking outdoors.
You can decrease your risk by modifying one of these three variables. If you want to see friends, avoid crowded bars, and instead host in your backyard or a park, where everyone can keep their distance. Use your own utensils and, to be even safer, bring your own food and drinks. Skip the hugs, kisses and handshakes. If you go to the beach, find areas where you can stay at least six feet away from others who are not in your household. Takeout food is the safest. If you really want a meal out, eating outdoors with tables farther apart will be safer than dining in a crowded indoor restaurant.
Businesses should also heed this principle as they are reopening, by keeping up telecommuting and staggered shifts, reducing capacity in conference rooms, and closing communal dining areas. Museums can limit not only the number of people allowed in at once, but also the amount of time people are allowed to spend in each exhibit.
Pooled risk. If you engage in high-risk activity and are around others who do the same, you increase everyone’s risk. Think of the analogy with safe-sex practices: Those with multiple partners have higher risk than people in monogamous relationships. As applied to covid-19, this means those who have very low exposure are probably safe to associate with one another.
This principle is particularly relevant for separated families that want to see one another. I receive many questions from grandparents who miss their grandchildren and want to know when they can see them again. If two families have both been sheltering at home with virtually no outside interaction, there should be no concern with them being with one another. Families can come together for day care arrangements this way if all continue to abide by strict social distancing guidelines in other aspects of their lives. (The equation changes when any one individual resumes higher-risk activities — returning to work outside the home, for example.)
Cumulative risk. Your risk of acquiring covid-19 is additive for every person you come into close contact with. Many people must return to work, but they can still reduce their risk overall by not having social gatherings outside of work. Choose the activities most important to you. If you must have your hair cut, don’t also go out to eat in restaurants.
How much you do should also depend on your personal health. By now, we know that those most vulnerable to the severe effects of covid-19 are older people with chronic medical conditions. These individuals should aim for lower cumulative risk to best protect themselves, as we keep up the reminder that there is no demographic immune from covid-19. Even otherwise-healthy children and young adults have died from it.
Collective risk. Individual actions are crucial, but they do not replace the need for sound public policy. The higher the rate of covid-19 in a community, the more likely any one individual you come into contact with has the virus and the riskier your interactions become. This is why mask-wearing is important: If most people wear a mask, it reduces the amount of virus that we will transmit. Local and state policymakers should continue to ban large gatherings and follow the CDC guidelines for gradual reopening. They must have surveillance systems in place to detect if and when infections rise and be willing to reimpose restrictions.
With Memorial Day coming and many locales lifting their shelter-in-place orders, people will be faced with new decisions. We need to use common sense and our own risk calibration, as we keep in mind that just because we can resume activities doesn’t mean we should.