I’m sorry if everyone is getting sick of reading about the pandemic but a paper was published in Science yesterday which is worth sharing. It’s called Projecting the transmission dynamics of SARS-CoV-2 through the postpandemic period. This is important because there’s been a lot of short-term thinking with sudden closures of schools and businesses but not much thought put into what happens next. It’s clear that social distancing slows the spread of the virus but it also seems likely transmission will rebound as soon as we restart the economy. Even more worrying is that there’s evidence that strong and temporary restrictions will lead to a larger resurgence later on. This is what happened during the 1918 flu pandemic.
The observation that strong, temporary social distancing can lead to especially large resurgences agrees with data from the 1918 influenza pandemic in the United States (44), in which the size of the autumn 1918 peak of infection was inversely associated with that of a subsequent winter peak after interventions were no longer in place.
It seems unlikely at this point that the virus will be eradicated which means it will be with us in the years to come. The authors note that intermittent restrictions may be required into 2022.
Intermittent distancing may be required into 2022 unless critical care capacity is increased substantially or a treatment or vaccine becomes available. The authors are aware that prolonged distancing, even if intermittent, is likely to have profoundly negative economic, social, and educational consequences. Our goal in modeling such policies is not to endorse them but to identify likely trajectories of the epidemic under alternative approaches, identify complementary interventions such as expanding ICU capacity and identifying treatments to reduce ICU demand, and to spur innovative ideas (55) to expand the list of options to bring the pandemic under long-term control.
This suggests to me that the virus will need to spread throughout the population in a controlled way such that ICU capacity is not exceeded and until we develop immunity either by way of a vaccine or having had the illness ourselves. Large-scale testing will help to slow the spread since it will allow us to identify asymptomatic cases and isolate them. This, of course, depends on people doing the right thing and staying home when they’re sick. We all know about patient 31 who went to religious gatherings, despite feeling unwell, where she infected thousands of other people. South Korea has had problems with people violating self-quarantine and in response is using electronic wristbands to ensure people stay at home.
We will need to increase critical care capacity, as is already happening, and find the least disruptive, as well as most effective, social distancing measures that can be maintained for the long term. I don’t know what these are or how it looks but I’ve heard talk of a staggered relaxing of restrictions in the UK with young people allowed to venture out first and primary schools and nurseries reopening initially. Universities and high schools may remain closed because those students don’t take parents out of work. There may also be geographic differences. For instance, those places that have already had a large number of infections can resume normal life more quickly while other places with fewer will need to be more careful. Only time will tell and I suspect we won’t be able to draw any major conclusions about the best course of action for at least another two years.