There are two schools of thought for the future of COVID-19. #ZeroCOVID is an emerging idea that all nations can nearly eliminate SARS-CoV-2 transmission, and occasional outbreaks can be rapidly dealt with by public health services. #HarmReduction is an alternate philosophy that emphasizes that the goal of policy is to minimize the harms of the virus, but #ZeroCOVID may not be possible.
Imperfectly pursuing perfection can be worse than steadily pursuing good. Which is the best path forward? Does it vary by country?
#ZeroCOVID
Recently, two articles fleshed out the idea of zero COVID. Indeed, #ZeroCOVID is seductive. After all, who doesn't wish for a world without SARS-CoV-2? Moreover, some countries appear to have achieved or been within striking distance of the dream. Australia and New Zealand are averaging four to six and two new cases a day, respectively. Citizens in those nations can go to parties, concerts, and restaurants. I'm envious!
#HarmReduction
Harm reduction is an alternative view with a longstanding tradition in public health. The core idea is that sometimes abstinence or perfect adherence to policies is not possible, achievable, or desirable among human beings. Human beings are beautifully complicated, and often they have competing desires that influence the short- and long-term goals. Policies can and should encourage actions to lower the harm or damage of the virus, and the realistic pursuit of good can be superior to imperfect pursuit of perfection.
What are the practical differences in these philosophies?
These two views lead to overlapping, but also divergent, recommendations. Both views may support similar restrictions amongst unvaccinated people: social distancing, masking, limiting large, indoor gatherings. Both would favor improved ventilation. Both would support vigorous testing and contact tracing. Both would have us vaccinate citizens with urgency.
Differences are also salient. Zero COVID might be more likely to favor repeated and strict lockdown measures -- with strong enforcement -- while harm reduction might seek to limit such measures. Zero COVID may favor protracted school closures, while harm reduction may weigh the societal benefit versus harms, and opt to open even if there is a minor increase in viral spread. (Full disclosure: I review the evidence for that claim here.)
Finally, zero COVID would favor that vaccinated people take all the same precautions as unvaccinated people, while the harm reduction philosophy recognizes that, in private, vaccinated people are going to hug their parents or grandchildren. I have also weighed in on this topic.
Which view is right for the United States or the United Kingdom? Can what has worked in Australia since March 2020 work in the U.S. now? To consider this question, we have to answer why some nations do better than others.
Why do some nations do better than others?
If one looks across all the nations on earth, it is clear that some countries do better. In addition to Australia and New Zealand, Vietnam, Taiwan, and Singapore have also had relatively few cases per capita. Spain, Portugal, and Israel are amongst the hardest hit nations. And there is a huge range between where the U.S. and the U.K. fall.
Why do nations do differently? It is a simple question, and on Twitter, many offer crowd-pleasing answers, but the truth is uncertain. Consider that there are at least six putative reasons why nations do differently:
1. We are measuring cases, hospitalizations, and even deaths, differently. Not all nations have the same access to and rate of testing, and many nations may have different criteria or rules for hospitalization, or receipt of intensive care. Collection, tabulation, and scrutiny of deaths also vary. These may even vary within a nation from March to October of 2020. Across nations, in the absence of a coordinated scientific effort, comparisons may be, at best, apples to oranges.
2. The choices made by governments or administrators or policy experts, and the choices made by citizens are one reason nations perform differently. Human actions are a popular explanation, perhaps even the favored explanation. Indeed, believing that all the differences between nations is due to our choices allows us to praise and condemn others. It is also quite natural to feel that our destiny is in our hands.
I am sure that human choices are a factor, but I don't know if they are the only factor, dominant factor, or which choices make a difference, as I described elsewhere. South Africa, Peru, and the Philippines all took strong, decisive actions, but have not had the same fate as Taiwan and New Zealand. It will take many years for research to clarify which governmental actions shape outcomes, and in what context.
3. Differences in early pandemic events. Many nations took action in March 2020 to combat the pandemic after horrific stories from Wuhan and Lombardy. Travel was suspended and borders closed. It is possible that even at this moment, there were already differences in starting conditions. Some nations or cities may have had more seeding events, and some dominoes might have been destined to fall based on initial conditions.
4. Differences in climate, the built environment, indoor vs outdoor spaces, temperature, seasonality, and geographic barriers. It is possible that some differences between nations are a property of the different environments within which humans live. Some nations may enjoy advantages, such as reduced density, or geographic barriers to mixing.
5. Differences in age structure, population, or population density. It is possible that some differences are due to the nature of the population exposed to the viral spread. The risk of bad outcomes rises rapidly with age, and some nations may have been spared because the population is relatively younger.
6. Randomness, stochasticity, chaos. One of the hardest things to consider about pandemic spread, and the fate of nations, is that randomness plays a role. Even if everything else was the same, if you replay the past year 100 times, it is possible there is a sizable variation in outcomes. Some nations that performed well may have done so in part due to chance. Early chance differences in pandemic spread may even themselves affect the choices humans make.
These are just six possible factors, but there are likely others. Thinking about the fate of nations in this manner raises the question that what works in some places may not work in others. The fact that a few places have achieved #ZeroCOVID does not ensure that all nations could achieve #ZeroCOVID, if this were their goal.
#ZeroCOVID vs #HarmReduction
Of course, I wish we lived in a world with #ZeroCOVID, but the question is given where we are now, can we get there?
Nations that are already within striking distance of the goal (such as Taiwan or Australia) might be able to sustain it. By testing travelers, or quarantining them after arrival, and by aggressively investigating outbreaks, these countries may be able to keep rates quite low until vaccination takes place, which is overwhelmingly likely to disrupt transmission chains.
Other nations, such as the United States and the United Kingdom, may need Herculean efforts to pursue #ZeroCOVID. As I write this, the 7-day average for new cases exceeds 100,000 per day in the United States. Vaccination now exceeds a million doses a day, but a non-trivial portion of the population is not eligible for vaccination (i.e., <16 years old) or is reluctant to be vaccinated. In the absence of drastic measures, I do not see a path to #ZeroCOVID in the U.S.
Proponents of #ZeroCOVID concur and note that a "short, intense lockdown" may be needed early on. Practically, this seems unthinkable in the United States. We are deeply divided, and some fraction of the population will not consent to lockdown. Protests are sure to occur. And military force may be needed to enforce this policy.
Lockdowns are a unique intervention. If you wish to combat drunk driving, you can mostly succeed even if there are a few violators. But if you wish to combat pandemic spread, your policy is only as successful as the least compliant people. A motivated fraction of the population can thwart the overall effect, by defying the measure and by actively seeking risky activity.
If I reflect on the United States politically at this moment, I cannot imagine a successful lockdown.
Meanwhile, vaccination changes the calculus. Across all vaccine trials to date, and 65,000 vaccinated participants, there are zero hospitalizations and zero deaths. Vaccination removes the fangs from the snake. If we can successfully vaccinate adults, particularly older adults, then eradicating SARS-CoV-2 takes on less importance.
Finally, policy is a series of trade-offs, and a sustained policy of #ZeroCOVID may entail severe downsides. At a minimum, societies might face restrictions on travel and movement. Unanticipated and strict lockdowns may lead to riots and strife.
Prolonged school closure may lead to a generation of kids with educational deficits, and loss of upward mobility. You can tell vaccinated people not to meet for dinner or lunch or to hug their parents whom they have not seen in a year, but I seriously doubt that they will adhere to that recommendation (and I still think the absolute risk is incredibly low, and consistent with many other risks we take in society every day).
In short, I am envious of all countries that are within striking distance of #ZeroCOVID, but given where the United States is in this moment, I struggle to think this is a realistic, feasible or practical goal for us. If you read my past columns, it should come as no surprise that I am of the school of public health that favors harm reduction. But I am curious about what you think?
Vinay Prasad, MD, MPH, is a hematologist-oncologist and associate professor of medicine at the University of California San Francisco, and author of Malignant: How Bad Policy and Bad Evidence Harm People With Cancer. The views expressed above are his own and not his institution's.