Health-care workers walk to a COVID-19 testing facility in Montreal on March 27, 2020.Ryan Remiorz/The Canadian Press
David Naylor is professor of medicine at the University of Toronto. Tim Evans is director of the McGill School of Population and Global Health who formerly served as a Global Director at the World Bank and assistant director general at the WHO.
Our country is in the grips of an unprecedented outbreak of a novel coronavirus that has already killed over 25,000 people worldwide. Canada is reporting hundreds of new cases daily and growing hospitalizations and deaths. And most Canadians are cocooned at home, heeding calls to help “flatten the curve” and stem the surge affecting our health-care systems.
Policy-makers meanwhile have a dilemma: how to suppress the epidemic, bolster health-care capacity and minimize economic contraction.
No one has a magic formula or perfect model to drive those decisions. However, we could be far better informed. Our rate of testing has accelerated, but the coverage is still well below that needed to give an accurate picture of the epidemic. Thousands of test results have been backlogged at various times, leading to intermittent and confusing spikes in case counts, even as tardy delivery of provincial case reports to the Public Health Agency of Canada has blurred our view of national outbreak demographics.
It’s not just information on active infections that is needed. We’ve learned that a substantial number of people infected with COVID-19 have minimal symptoms – not least children, teenagers and young adults. That sounds ominous, but there’s a silver lining. Background immunity to COVID-19 may be higher than imagined, which in turn has dampening effects on the spread of the virus. As of today, there is no plan to determine levels of immunity to COVID-19 in Canada.
So what is to be done?
First, a substantial wave of COVID-19 patients will hit our hospitals in the days ahead. Intense preparations are under way across Canada with remarkable creativity and commitment. However, with caseloads spiralling up in countries like the U.S. and Britain, global competition for personal protective equipment and other clinical necessities will become cut-throat. Canada’s governments must intensify their collaborative procurement efforts to avoid hospitals and ICUs being overrun. If that happens, we know the outcome – massive rises in morbidity and mortality, not least among health-care workers.
Second, detailed de-identified data must be shared in real time with a range of trusted analysts, inside and outside governments, so decision-makers and the general public can get a clearer picture of where we are and what lies ahead. Most citizens have done their bit brilliantly, and they deserve nothing less than radical transparency.
Third, managing COVID-19 risk and response defies a one-size-fits-all approach. Flattening the curve – an important aim – means limiting the relative rate of growth in new COVID-19 cases. However, global data show that deaths and cases per million are weakly aligned, because more testing front-loads the identification of cases even as it facilitates containment. What decision-makers need, accordingly, is a balanced scorecard synthesizing the demographics and risk profiles of new and existing cases, and linking those profiles to testing patterns, hospitalizations, ICU admissions and deaths.
If that scorecard sends danger signals, intensification of physical distancing must be done at once. The playbook for those lockdowns is obvious from other jurisdictions, but so is the toll. A total lockdown adds to the already considerable burden on Canadians who are economically and socially vulnerable. Unemployment, impoverishment and the destruction of seniors’ social networks could take a larger health toll than COVID-19 itself if we do not find an exit strategy.
Identifying the exit strategy will be greatly facilitated by two key steps. The first is massive augmentation of capacity for testing and contact-tracing on a scale seen in other nations that have reduced the COVID-19 case flow to a manageable stream. Surveillance for the disease must cover vulnerable populations, such as long-term-care residents and staff as well as all health-care workers, and be widely scaled in the community as soon as possible. The second is implementing a sero-surveillance strategy where small samples of blood are rapidly tested for antibodies to COVID-19 in order to determine immunity. These tests are widely available now. By using them wisely, we can estimate levels of background immunity in different groups, changes in immunity over time and how immunity relates to viral shedding. Such insights could inform safe deployment of public-facing essential workers.
The information would not only help inform short-term decisions about physical-distancing measures and support front-line health-care responses, it would build public-health capacity for long-term containment and guide the toggling of severe physical-distancing measures that are strangling the economy. Last, and not least, it would buy precious time as we await results of ongoing trials – many led by Canadians – that are testing old and new drugs with the potential to radically change the course of this disease.
Keep your Opinions sharp and informed. Get the Opinion newsletter. Sign up today.