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A New Approach to COVID-19 Response
By Joel Zinberg of CEI.
"The new coronavirus—SARS-CoV-2, which causes the disease COVID-19—is
here to stay until either a vaccine or herd immunity limits the number
of people susceptible to transmission. A vaccine is a year or more away.
So why do we continue to pursue lockdowns that ensure herd immunity
will never develop and the virus will continue to fester?
The answer usually given is that we must “flatten the curve.” The
pandemic curve, a roughly bell-shaped curve, shows the number of new
infections rising and then falling over time. With a highly
transmissible virus the curve will have a high peak, with a steep ascent
and steep descent on either side. If measures are taken to limit
transmission the curve will be flattened—the slope will be more
moderate, and the peak will be lower—but the process will play out over a
longer period of time and the total number of infections will not
necessarily be any different. And, barring a vaccine, once measures are
relaxed the number of infections will rise again because herd immunity
never had a chance to develop and there are still enough susceptible
people to fuel transmission.
The pandemic curve translates into a similar curve of how many people
will, after being infected, become seriously ill and require
hospitalization and intensive care unit (ICU) care, which could include
ventilators. Health care planners were afraid that with a steep curve
there would be large numbers of patients needing ICU care and
ventilators all at the same time and that the health care system’s capacity would be overwhelmed.
That would increase the number of deaths as both COVID-19 and non-COVID
patients were unable to obtain care. They prescribed suppression
measures including social distancing of the entire population and school
closures. Delaying and lowering the utilization peak would give
hospitals time to increase capacity and supplies and allow more time to
develop treatments.
But the planners were wrong. Outside of a small number of hospitals
in a few hotspots, U.S. health care capacity was not overwhelmed. In
fact, many hospitals, forced to suspend elective procedures, have plenty of empty
beds. The additional bed capacity that New York built went largely
unused. This underutilized capacity is not proof that a lockdown is
superior to less aggressive mitigation measures. Despite widespread
criticism that Britain waited too long to impose suppression measures,
its poorly resourced health system was not overwhelmed.
Sweden, which has been roundly criticized for not imposing society-wide
social distancing and school and business closures, has never come
close to having a shortage of ICU beds.
From the start, planners misjudged the height of the
hospitalization/ICU curve because they overestimated how deadly
infection with the virus is. They were undoubtedly influenced by scenes
of overwhelmed Italian hospitals and reports of doctors forced into
tragic choices as to who would receive care and who would die. But the
Italian experience was not applicable here.
COVID-19 is especially lethal among older people—95 percent of COVID-19 deaths in Europe and 85 percent in New York
were in people 60 and older; only 2 percent of New York deaths are in
people under 40. Older COVID patients are also far more likely to have
severe cases needing hospitalization.
COVID-19 hospitalization rates for people over 65 are double the rates
for ages 50-64 and six times the rates under 50.
Hospitalizations below
age 18 are rare. Italy’s population is disproportionately elderly.
Twenty-three percent of Italy is 65 or older. The comparable U.S. figure
is 16 percent. And the U.S. was better prepared. While the U.S. has
roughly the same number of hospital beds per capita as Italy, we have
nearly three times
as many ICU beds per 100,000 population as Italy has. The U.S. has more
than twice as many modern ventilators per capita as Italy and the
number of U.S. ventilators could more than double
if older, less full featured units are pressed into service. Finally,
Italian cases rose several weeks before the U.S., so the U.S. had time
to institute mitigation measures at an earlier phase of the pandemic.
Planners were also concerned that COVID-19 could be as severe as the
1918 influenza pandemic, where 50 million people died worldwide
including 675,000 in the U.S., because both pandemics involve a new
virus for which the population had little or no immunity. But the 1918
pandemic had a unique mortality distribution not seen before or since.
While seasonal influenza typically has mortality peaks among the very
young and very old, the 1918 pandemic was especially lethal among young
adults—nearly half the total deaths were in the 20-40 age group. The
absolute risk of death was higher in those younger than 65 than in those who were older. In contrast, COVID-19 deaths are heavily concentrated among the elderly.
Finally, planners were influenced by high initial fatality
estimates—on March 3 the World Health Organization (WHO) reported a
fatality rate of 3.4 percent.
But that estimate was artificially high because it calculated rates
based on deaths (the numerator) among known cases (the denominator),
which were the more severe cases. Asymptomatic and mild cases went
uncounted. The WHO report also erroneously reported that the number of
asymptomatic infections was only 1 percent.
Some epidemiologists suggested the true number of infected people in the U.S. is far higher than the number of confirmed cases. One study
of excess influenza like illnesses reported by the Centers for Disease
Control and Prevention suggests that a high percentage (87 percent) of
symptomatic COVID-19 cases were not identified because they were never
formally tested. In addition, reports from California, New York, and Europe found that most COVID-19 infections are asymptomatic and go undetected. A report from prisons in four states shows that large numbers of prisoners are testing positive and 96 percent are asymptomatic.
If the true numbers of symptomatic and asymptomatic COVID-19
infections are grossly undercounted, it would lead to two encouraging
conclusions: First, the fatality rate is far lower than feared. Second,
there is probably a large repository of people who were infected, have
recovered, and now have antibodies making them immune to future
infection. A study of confirmed COVID-19 cases in New York showed that they reliably develop antibodies, likely making them immune. Another study
of random samples in New York City found more than 20 percent of people
test positive for antibodies. This indicates we may be closer to the
herd immunity that usually signals the end of pandemics than has been
appreciated.
Good serology studies are imperative to determine how prevalent
antibodies are in the population. The Food and Drug Administration has
given emergency approval
to new, highly reliable tests that should facilitate the process. If
infection rates are high, lockdown measures should be relaxed.
This does not mean ending all measures. Public health measures to
combat COVID-19 are a continuum. Applying just three mitigation
interventions—home isolation of known cases, voluntary home quarantine
of household contacts of cases, and social distancing of those over
70—was predicted to lower peak health care demand by two thirds and deaths by half. A recent MIT study
found that targeting mitigation policies to the most vulnerable,
elderly population would actually lower fatalities and economic costs,
compared to measures applied uniformly to the entire population. Continuing school closures and social distancing of the entire
population makes little sense, since younger people have a near-zero
risk of serious complications and death from COVID-19. Allowing the
young to be in environments where they risk exposure to infection is
possible if we continue protection measures for the most vulnerable—the
elderly and those with underlying medical conditions.
Testing, targeting our efforts at protecting the most vulnerable, and
relaxing public health measures as local circumstances dictate, will be
an ongoing process. This course is far preferable to another year of
lockdown while we await a vaccine that may or may not come."
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