

COVID-19 – ending isolation
SciLine reaches out to our network of scientific experts and poses commonly asked questions about newsworthy topics. Reporters can use these responses in news stories, with attribution to the expert.
What are Quotes from Experts?
July 30, 2020
With COVID-19 cases rising again, are there lessons learned that inform how officials should go about slowing new waves of transmission?
“Preventing and managing new waves of COVID-19 will require a multi-faceted response, including wearing masks, physical distancing, frequent hand washing, and limiting the sizes of gatherings. No single one of these elements will be enough on its own, but together, they can help slow the spread of COVID-19 substantially. Governments and employers should ensure that essential workers have the supplies they need to keep themselves and their communities safe (e.g. masks and hand sanitizer) and should also guarantee paid time off if an employee becomes ill or is exposed to someone with COVID-19. Finally, frequent testing remains absolutely necessary. As cheap COVID-19 tests become available, policymakers should invest in them and encourage as many people to use them as possible, as frequently as possible (up to 1x/day). This way, infectious individuals can self-isolate and inform their recent contacts of potential exposure, even if they are not showing active symptoms. This may be our best hope to avoid the wide-spread lockdowns we experienced during the spring.” (Posted July 30, 2020)
Stephen Kissler, PhD
Postdoctoral Fellow in Immunology and Infectious Diseases at the Harvard T.H. Chan School of Public Health
“Interconnections and mobility are really important. People are still moving around a lot, which means local leaders cannot let down their guard because infected people are always arriving to seed new outbreaks. Non-targeted distancing measures buy time for innovation, but we need to do a better job hedging against the possibility that there will not be a pharmaceutical breakthrough in the coming months. We need a real test and isolate program that leads to targeted distancing.
“One option is for programs to make use of pooled testing. If community members are interacting outside the house on a regular basis, then they need to be tested twice per week in an easy and convenient fashion, and they need the results in less than 24 hours. The technology exists to do this around the price of a cup of coffee per person per day. With a six- to eight-day delay in test reporting, the testing is doing nothing for public health. By the time people get their results they are through the infectious period. If testing is done frequently, we don’t need to obsess with accuracy (though it needs to be good). For example, if you are infectious and are tested once per week with a 2% chance of a false negative, you actually have greater chance of going undetected than if you are tested twice that week with a 14% chance of a false negative.” (Posted July 30, 2020)
Eli Fenichel, PhD
Knobloch Family Professor of Natural Resource Economics, Yale School of the Environment
April 28, 2020
How will states or communities know when to relax current social distancing measures?
“There will be some trial-and-error to this. SARS-CoV-2 is likely to spread at different rates in different places at different times of year. After cases have been declining for a few weeks, it may be reasonable to start lifting some social distancing measures. The most important thing will be to maintain widespread testing and surveillance so that we can know immediately if or when cases start to rise again and put adequate measures back in place.” (April 28, 2020)
Stephen Kissler, PhD
Postdoctoral Fellow in Immunology and Infectious Diseases at the Harvard T.H. Chan School of Public Health
“The only way to know when to relax current social distancing measures is with expanded testing. The idea here is that social distancing is currently our only real tool to reduce the size of the outbreak. When testing is limited, we can’t be sure who has the disease and that means we have to use that tool on the entire population. With a massive increase in testing capacity we can identify cases and then trace their contacts much more precisely and use targeted social distancing to prevent further spread.” (April 28, 2020)
Ryan Malosh, PhD
Assistant Research Scientist, University of Michigan School of Public Health
“Without active tracing measures, a second wave of infection is inevitable. We have to work to identify the best strategies for that before relaxing social distancing.” (April 28, 2020)
Esteban Moro Egido, PhD
Visiting Professor, MIT Media Lab; Associate Professor, Universidad Carlos III de Madrid
“This is really challenging. Communities and even states are not isolated. Even if a region controls the epidemic locally, relaxation followed by spillover from somewhere else could start it back up. The safe time would be if a lot of people have acquired immunity—though this probably follows a bad outcome—or if there is a really great track, trace, and isolate system in place.” (April 28, 2020)
Eli Fenichel, PhD
Knobloch Family Professor of Natural Resource Economics, Yale School of the Environment
What strategies for relaxing social distancing are best to prevent a resurgence of infections and cases?
“We don’t currently know, but a lot more research should be available on this soon. For example, we’re still not sure how much children contribute to transmission, and answering this question will help us determine whether or not widespread school closures are an effective way of reducing transmission. With different states and different countries all trying slightly different social distancing measures, we should be able to compare the efficacy of these measures against each other and thereby tailor our future social distancing measures more effectively.” (April 28, 2020)
Stephen Kissler, PhD
Postdoctoral Fellow in Immunology and Infectious Diseases at the Harvard T.H. Chan School of Public Health
“It is likely that any relaxation will lead to some resurgence. The goal would be to have the resurgence be monitored and contained. So you relax guidelines for some people first, do extensive testing to watch for a resurgence and then, if all goes well, you can relax guidelines for others. Priorities for who should have their restrictions relaxed first will need to be determined at the local level with a lot of different stakeholders included in those decisions. The populations that are identified as high risk of severe disease would likely be last to have their restrictions relaxed.” (April 28, 2020)
Ryan Malosh, PhD
Assistant Research Scientist, University of Michigan School of Public Health
“Without active tracing measures, a second wave of infection is inevitable. We have to work to identify the best active strategies before relaxing social distancing. Our research shows that testing, active tracing and targeted quarantine (the “new normal”) can prevent the second wave when current social distancing measures are relaxed. Reliability of contact tracing measures, their level of compliance and their effectiveness are key factors to assess how and when to restart our normal activity. Because of that, we need better knowledge about how social distancing is impacting our communities and constant monitoring (at aggregated level) of how they embrace the ‘new normal.’” (April 28, 2020)
Esteban Moro Egido, PhD
Visiting Professor, MIT Media Lab; Associate Professor, Universidad Carlos III de Madrid
“Isolating infectious individuals is really important, followed by prioritizing those with acquired immunity to return to work, though that creates some difficult incentives. There may be opportunities to target on other risk factors, but we are still trying to figure that out.” (April 28, 2020)
Eli Fenichel, PhD
Knobloch Family Professor of Natural Resource Economics, Yale School of the Environment
Will social distancing be necessary in the future?
“Yes, almost certainly. Experience from past pandemics, especially the 1918 influenza pandemic, shows that when social distancing measures are lifted, a resurgence in cases follows. Our mathematical models also show this. To prevent these resurgences from overwhelming hospital resources, we will likely need to continue social distancing, even if just intermittently, for some time.” (April 28, 2020)
Stephen Kissler, PhD
Postdoctoral Fellow in Immunology and Infectious Diseases at the Harvard T.H. Chan School of Public Health
“Unless we find a vaccine, non-pharmaceutical interventions like social distancing are going to be part of our lives in the near future. They might not be full lockdown or shelter-in-place but we will have to adapt our lives to targeted quarantines of individuals or places.” (April 28, 2020)
Esteban Moro Egido, PhD
Visiting Professor, MIT Media Lab; Associate Professor, Universidad Carlos III de Madrid
“Over the coming weeks – yes. In the long-term, probably not permanently, but other epidemics are certainly possible.” (April 28, 2020)
Eli Fenichel, PhD
Knobloch Family Professor of Natural Resource Economics, Yale School of the Environment
What signals might indicate a need to return to more aggressive social distancing?
“If we are able to conduct widespread testing, we will be able to monitor the prevalence of illness. Using mathematical models and past experience from this outbreak, we will be able to set thresholds to advise social distancing when prevalence rises above that level. In the absence of widespread testing, we may be in the dangerous scenario of triggering aggressive social distancing only when hospitals start to fill up again. This will be too late; we will run the risk of overshooting our hospital capacity, since cases arriving to the hospital reflect transmission that happened 1-2 weeks before. This underscores the importance of maintaining widespread testing in the months to come.” (April 28, 2020)
Stephen Kissler, PhD
Postdoctoral Fellow in Immunology and Infectious Diseases at the Harvard T.H. Chan School of Public Health
“Any uptick in cases would indicate a need to reinstate at least some of the social distancing guidelines. This is why testing is so important to the strategy. Hopefully we would detect an increase early, before a corresponding increase in cases needing hospitalization or critical care.” (April 28, 2020)
Ryan Malosh, PhD
Assistant Research Scientist, University of Michigan School of Public Health
“This is tough. The signals we are getting are really noisy. The case measurement is poor. Death measures might also be poor. Basically, we need more testing in some sort of sampling regime – probably stratified random sampling.” (April 28, 2020)
Eli Fenichel, PhD
Knobloch Family Professor of Natural Resource Economics, Yale School of the Environment
Should certain vulnerable groups continue practicing social distancing, even after restrictions are relaxed?
“Probably so. COVID-19 illness can be much more severe for the elderly and the immunocompromised, as well as other at-risk groups. Individuals in these high-risk groups will likely need to be more cautious in the coming months than individuals at lower risk of severe infection.” (April 28, 2020)
Stephen Kissler, PhD
Postdoctoral Fellow in Immunology and Infectious Diseases at the Harvard T.H. Chan School of Public Health
“I am a member of a vulnerable group, as I am currently in remission from leukemia and recovering from a bone marrow transplant. I know that I will continue to practice social distancing until it is clear that the risk of infection from the community is very low. I anticipate that CDC and other public health authorities will make similar recommendations for vulnerable groups.” (April 28, 2020)
Ryan Malosh, PhD
Assistant Research Scientist, University of Michigan School of Public Health
“Social distancing is creating more vulnerable groups because not everybody has the luxury to work from home, home-school their children, or shelter-in-place. It is important that, whatever the measures we put in place during the restrictions or when social distancing measures are relaxed, we consider their varying impact on different socio-economic groups. We have never been more segregated than today, with most of the population staying in their neighborhoods. Let’s not leave behind the most vulnerable groups.” (April 28, 2020)
Esteban Moro Egido, PhD
Visiting Professor, MIT Media Lab; Associate Professor, Universidad Carlos III de Madrid
“I think people should wash hands and take general precautions. I think sensitive groups should be slower to relax than non-sensitive groups.” (April 28, 2020)
Eli Fenichel, PhD
Knobloch Family Professor of Natural Resource Economics, Yale School of the Environment
Stephen Kissler, PhD, Postdoctoral Fellow in Immunology and Infectious Diseases at the Harvard T.H. Chan School of Public Health, said:
I have no conflicts of interest to report.
Esteban Moro Egido, PhD, Visiting Professor, MIT Media Lab; Associate Professor, Universidad Carlos III de Madrid, said:
None
Eli Fenichel, PhD, Knobloch Family Professor of Natural Resource Economics, Yale School of the Environment, said:
None
Ryan Malosh, PhD, Assistant Research Scientist, University of Michigan School of Public Health, said:
None