October 16, 2020

Lock 'em up!

            A provocative, contrarian position paper (somewhat ostentatiously and bizarrely entitled by its authors a “declaration”) is creating a stir by advocating “focused protection” as a means of dealing with the Covid-19 pandemic. The strategy of “focused protection” as defined by the 3 principal architects of the “declaration” recommends 3 different approaches for 3 different segments of the population: for those at highest risk of death from Covid-19, individuals over 85, they recommend a lockdown; for those at moderately elevated risk, including those who are “retired” (aka people over age 65), they advocate a “safer at home” policy—delivery of groceries and other essentials, and staying home  except for socially distanced outdoor visits with friends or family; for those under 65, they suggest a resumption of normal activities. This algorithm, they argue, would allow the development of herd immunity in the general population by assuring that roughly 70 percent of them be allowed to contract the virus, leading to the end of the pandemic.

            Scathing critiques of this proposal are appearing daily. They discuss issues such as the failure to take into account the burdens of Covid-19 short of death (for example, the long-term sequelae that have increasingly  been reported) and the ethical and practical problems of effectively locking up all older people who live in congregate housing of any kind, not to mention the ethical and practical problems of vastly restricting the activities of everyone over age 65 who doesn’t live in congregate housing. These are legitimate concerns. I’m going to add to the growing list of critics by focusing on two others: the ageism of the proposal and, what is more surprising, the failure to recognize that a rare event that afflicts a large number of people produces a commensurately large number of casualties.

            First, ageism.  The authors of the proposal never explicitly acknowledge that the total population over age 65 in the US is now over 53 million people. This number doesn’t include the millions of people who are in the high-risk category, who would also be locked down, who are under age 65 but have important underlying health conditions. The authors seem to imagine that the most vulnerable individuals, those over age 85, account for most of the excess deaths and that all of them live in nursing homes. In fact, only 4 percent of the elderly population live in nursing homes, or about 1.3 million people. The authors also seem to assume that limiting contact by older individuals with the rest of the world will prevent them from becoming infected; they have apparently forgotten that the effectiveness of sequestration depends on the prevalence of the disease in the surrounding community: if all the nursing assistants and grocery delivery people are allowed to get sick, then their chance of transmitting the virus, even with relatively limited contact, will go up.

             Perhaps the lead authors of the paper, all of whom are under age 60, assume that everyone age 65 or older is superannuated. They should be reminded that fully half of the members of the US Senate are over age 65, as of course is the current president and his challenger. Not only do many older people work (16.4 percent, or 8.69 million), but the 65+ set account for a disproportionate share of consumer spending. How will the rest of society be able to “go about their business” without older people to come to their restaurants, stores, and performance venues? And parenthetically, if the 8.69 million people over age 65 who are still working are exhorted to behave just like their younger counterparts, i.e. to “go about their business,” and even assuming that most of these individuals are 65-74 (though this is not strictly true—14 percent of senators, for example, are over age 75), then the projection is that about 152,000 of this group would also die of Covid-19).

            Second, a small number multiplied by a very large number can be a large number. Let’s look at the segment of the population among whom the “declaration” suggests the virus should run rampant. Americans aged 55-64, like their younger counterparts, are advised to go about  unfettered by regulations. As of 2019, this group included 42.44 million people. If herd immunity is to be achieved, an estimated 70 percent of them would have to contract Covid-19, or 32.68 million people. Now here’s the tricky part. We need to know what fraction of people in a given age group are likely to die from Covid-19. The number that is commonly cited is the case fatality rate, or the fraction of people with documented infections who die. But what we really want to know is the infection fatality rate (IFR), or the fraction of people who have contracted Covid-19, whether they know it or not, whether they are symptomatic or not, who actually die from the disease. Computing that rate depends on accurately determining the prevalence of Covid infection in a particular population and the death rate in that group. The best measure I have seen for the IFR for people age 65-74 is 2.5; the IFR for the 75-84-year-old group is 8.5; and the IFR for the 85+-year-olds is 28.3.

            But what about those who are 55-64? Their IFR is .75, so the authors of the “declaration” deem them safe. But if 32.68 million people in this age group contract Covid-19, and .75 percent of them die, then that means, by simple multiplication, that there will be 222,810 deaths in this group alone. A small number (.0075) times a large number (32.68 million) is a pretty big number when we’re talking about human lives. 

             For that matter, why stop with the 55-64-year-olds? Why not consider the 45-54-year-olds? They make up 40.88 million people. If 70 percent contract the virus (after which there should be herd immunity and the virus will vanish), that’s 28.16 million people. The IFR for this group is .068, which translates to 29,708 deaths. Is that acceptable?

            To determine what number of deaths is too many, some commentators have compared the numbers to flu deaths; others have compared them to automobile deaths. The fallacy is to assume that either you open society completely (to selected age cohorts) or you have a complete shut-down. That’s no more accurate than assuming that either people are allowed to drive cars and die in automobile accidents or they aren’t allowed to drive and no one dies. The reality for driving is that there are some mitigating steps we can take, such as seatbelt laws and speed limits on roads, which will significantly decrease the risk of death. In the case of Covid-19, mitigation means exactly what the majority of public health experts currently advocate: masks, social distancing, limiting the size of indoor gatherings, and substituting work at home for work in the office whenever possible. 

            When scientists band together to make an argument that is intended to influence public policy, they write a “position paper” or a “white paper” or an “open letter.” The “Great Barrington Declaration” reveals in its very name that it is something different. It is an ethical perspective masquerading as a technical brief. The authors claim their case for what to do in the setting of the pandemic arises logically from the data. In fact, their strategy, like all strategies for dealing with the outbreak, requires balancing personal freedom and the social good. The “declaration” implicitly assumes that the quality of life of older people is of no consequence and that a society has no special responsibility to its most vulnerable members. It dismisses the anticipated huge amount of death and disability among people under 65 by sleight of hand. Even if this policy could effectively be implemented—if allowing the virus to multiply unchecked would not overwhelm the health care system, causing people suffering from non-Covid conditions to suffer, if older people sheltering in place would remain uncontaminated as the disease becomes rampant in the workers who bring them their food and other services—this is not a policy that most Americans can endorse. The moral fiber of the American people may have been frayed in recent years, but it has not broken entirely.

No comments: