
So, You Thought Self-Isolating Was Hard….
For the past several weeks, most of us have been sheltering in place, kept home both by governmental orders and by our own desire to escape infection or to avoid infecting others. Finally, just as quarantine fatigue was setting in, some of those restrictions are being lifted.
But even as we begin to rejoice, we also begin to realize: suddenly, we have decisions to make. During “lock-down,” there were few of those. We may have thought about if or when to go to the grocery, whether or not to order take-out or delivery from a restaurant, or how long to let the mail sit outdoors before opening it. But with most things closed, we didn’t have to think about things like whether or not we’d chance a trip to the hair salon.
As we begin to consider such things, it’s crucial to remember we are not back to the “out-and-about” we knew in early March. Rather, it’s a constrained, tentative out-and-about, where each of us must make decisions about the risks we’re willing to take—for ourselves, our loved ones, and our communities.
How to think about your new freedoms: Start with as objective a self-assessment as possible. This will help you think about your risk of serious illness, should you become ill with COVID-19. For example:
- Do you have a chronic disease, such as diabetes, hypertension, COPD, or heart disease?
- Do you smoke?
- Are you immuno-compromised, either from a disease or from treatment for a disease (e.g., from chemotherapy)?
- Are you age 60 or older?
Next up, similarly assess others who live in your household. Maybe you’re not at high risk—but how about them? How might they fare, were you to bring COVID-19 home with you?
Thinking about expanding your circle to include a cherished family member or friend you’ve been keenly missing? Consider how “risky” they are—i.e., do they live alone, reliably self-isolating and observing recommended precautions? Or do they live with multiple other people, or work as frontline staff at an essential business?
Consider also the risk involved with any place you’re thinking about going. If you’re not sure how to go about that—no worries: the Center for Health Security (CHS) at the Johns Hopkins Bloomberg School of Public Health has already done the work for you.
CHS assessed the risks you might encounter in multiple sectors of the economy—e.g., “nonessential” businesses, schools, outdoor spaces, and community gathering spaces. The three factors CHS focused on were:
- Contact intensity: Will you be close to or distant from others? Will your contact be short or prolonged? More intense (close/prolonged) contact is riskier.
- Number of contacts: How many people will you likely encounter? The more people you encounter, the higher the risk.
- Modification potential: How modifiable is each environment, in terms of mitigating risk?
Each factor was rated on a scale of high, medium, or low. Some example assessments:

- Practice social distancing, aiming for a six-foot distance between you and other people.
- Wear a face mask in public settings.
- Wash your hands often with soap and water. Use hand sanitizer that is at least 60 percent alcohol if soap and water are not available.
- Avoid touching your face.
How to think about COVID-19’s future:
COVID-19 will not end with 2020. The reason it won’t just “go away” after this first pandemic outbreak is the same as the reason its arrival caused a pandemic to begin with: no one was immune.
By the end of 2020, we will not be close to achieving the level of population immunity required to contain the virus (about 60 percent of the population). Until that happens—via vaccination or exposure—COVID-19 outbreaks will continue to occur. The only real questions are how big the surges will be, where they will occur, and how long they will last.
Get comfortable assessing and mitigating COVID-19’s risks. They will be with us for a while.
How We Arrived at the Point Where We Can Begin to Reopen
You may wonder how that happened, given one criterion for easing restrictions was that the number of new cases per day needed to decline for 14 consecutive days. That wasn’t yet the case here in Delaware by May 8, when restrictions began to ease. What gives?
Chiefly, people realized (worldwide) there needed to be a new-and-improved way to count, given the lack of tests early-on. Way back two months ago, it was very difficult to get tested for SARS CoV-2, the virus that causes COVID-19. There were so few tests that people had to meet strict criteria just to “qualify” to be tested. Between a lack of tests and the strict criteria, the number of people diagnosed with COVID-19 was low.
As tests became more available, more people began to be tested, resulting in (surprise!) an increased number of people diagnosed with the virus. Tests are even more available now—including drive-through testing open to all—so, yet more people are being diagnosed. If you’re looking at just the numbers, they aren’t going to go down very fast under this scenario.
Enter the “test-positivity rate,” i.e., the percentage of tests found to be positive. It provides a more meaningful measure for decline. Here’s how it works:
- Let’s say that, on three consecutive days, there were 50, 75, and 100 positive COVID-19 test results. Clearly, those numbers are increasing.
- But let’s also say that, on those same days, a total of 500, 1,000, and 1,500 tests were administered.
- That would give us a test-positivity rate for those days of 10 percent (50/500), 7.5 percent (75/1,000) and 5 percent (100/2,000), respectively.
The test-positivity rate decreases, even as the sheer number of positive results increases. This rate is the one used as evidence of decline here in Delaware (https://myhealthycommunity.dhss.delaware.gov/locations/state).
At the time of this writing, Delaware’s early-May test-positivity rates hover around 20 percent, which is relatively high. It likely results from targeting for testing those people who are more likely to be positive—e.g., those working in certain industries, such as processing plants or long-term care. Targeting makes sense—it just also makes for a higher test-positivity rate. A rate indicative of widespread availability of tests and population-wide testing (and of an epidemic that is coming under control) would be much lower.
Marj Shannon is an epidemiologist and wordsmith who has devoted her life to minutiae. She reports that yes, the devils are in the details.
1. Rivers C, Martin E, Watson C, Schoch-Spana M, Mullen L, et al. Public Health Principles for a Phased Reopening during COVID-19: Guidance for Governors. Center for Health Security, Johns Hopkins Bloomberg School of Public Health. April 17, 2020.
2. Begley, S. “Three potential futures for COVID-19: recurring small outbreaks, a monster wave, or a persistent crisis.” STAT. May 1, 2020.
3. Meyer, R & Madrigal, A. “A New Statistic Reveals Why America’s COVID-19 Numbers Are Flat.” The Atlantic. April 16, 2020.