As the COVID-19 pandemic spread to the U.S., authorities scrambled to find the best response, despite incomplete information, in the face of enormous public pressure. Because of this pressure, overreaction was viewed as less risky than underreaction.
The response in many areas was swift and impressive. Shutdowns were mandated. The stock market crashed, and the economy faltered. As the policy of widespread social distancing was adopted, any governors or local officials that did not advocate for complete shutdowns were derided as irresponsible and contributors to the deaths that would inevitably follow.
But there have been and will be unintended consequences to the current mitigation policies, undoubtedly. These have prioritized the health of COVID-19 patients over the health of others. Some individuals with chronic health problems have experienced delays in their health care, and others, cooped up in assisted living facilities under lockdown, have had their mobility, and health, compromised. Potentially lifesaving trials of cancer drugs have been canceled. Many low income individuals have lost the ability to make ends meet. Small businesses that supply many essential jobs have scrambled to adapt to strict restrictions. Many businesses will not survive. As this crisis continues, the mental health of communities like ours will decline, and the signs — suicides, drug and alcohol abuse, crime, and domestic violence, will increase. Lives will be lost.
In the face of the vocal majority calling for shutdowns and quarantines of healthy people, the response of the authorities in the United Kingdom was an outlier. The presumptive goal of this strategy was to allow “herd immunity” to develop in the young, healthy population with a low risk of developing severe disease. For COVID-19, herd immunity is estimated once approximately 60% of the population has been infected and recovers, slowing transmission due to lack of new, susceptible hosts.
Nationally and internationally recognized experts wasted no time in weighing in on the folly of this strategy. Many of their arguments were reasonable, from a lack of a necessary accompanying plan to increase testing and contact tracing, to the related issues of asymptomatic carriers and their inevitable contact with vulnerable individuals. Even worse, mathematical models showed that if strict social-distancing measures were not introduced, a huge spike of hospitalizations would overwhelm hospitals. Under enormous pressure, the British authorities changed course and shutdowns were mandated.
However, in the last week, COVID-19 projection models were updated, drastically. Projected deaths from Washington State’s Institute for Health Metrics and Evaluation (IHME), the source of projections for the White House and many state governments, were decreased by 35%, almost overnight, and may decrease further. The new projected number of deaths, while not trivial, are comparable to the result of an average flu season in the United States.
Much of the decrease in projected deaths was immediately hailed as a victory of social distancing and other mitigation policies. Yet, mitigation policy mandates were already factored into the models for each state. Since many of the early calculations were based on the other numbers released from the Chinese government, it is not unreasonable to assume that others may also be inaccurate, like the case fatality rate. The true case fatality rate for COVID-19 has been difficult to calculate, as it remains unknown how many mild and asymptomatic cases have occurred. It is also not unreasonable to assume that the Chinese government, which is not known for transparency or accountability, would suppress valuable information on the total number of cases and deaths.
The question that arises in the midst of this uncertainty is: How do we go forward? The current mitigation strategies were not enacted to prevent spread of the infection, only to delay it. Thus, quarantining of healthy people only ensures that a susceptible population remains to transmit the disease to older, more vulnerable people. Therefore, another surge of cases and deaths might occur in the coming months if mitigation policies are relaxed.
However, at some point, as individuals become immune to COVID-19 due to exposure and infection, the nation moves closer to true herd immunity, and an end to the COVID-19 pandemic. Young, healthy people could instead be viewed as protective assets instead of disease-spreading liabilities.
The amount of time for both mitigation and herd immunity strategies, and the cost in terms of lives, are hard to calculate in the absence of increased testing. Waiting for a vaccine, which could take years, does not seem a viable option. The path forward will likely combine both strategies, and will still require risks and sacrifices. We will need to identify the population of immune individuals, through widespread testing for serum anti-COVID-19 antibodies.
The numbers of exposed people may be surprising. It is possible that for every case that has been identified, 10-100 or more cases have gone undiagnosed, making herd immunity more attainable. I hope in the coming days that the necessary debates of the risks of both strategies will be made in good faith, and will lead to the best policies that benefit everyone.
Steve Templeton is the Alvin S. Levine Scholar and an Associate Professor of Microbiology and Immunology at the Indiana University School of Medicine-Terre Haute.