Is the Coronavirus Unprecedented?

Over and over, we see it asserted that the Wuhan epidemic is an “unprecedented” public health crisis. In what sense is that true? Certainly the reaction to COVID-19 is unprecedented; never before have we substantially shut down our country as a public health measure. But is the virus itself really unprecedented in its lethality or its impact on public health?

A reader writes:

I’m surprised that so little has been written about what, if anything, we can learn about the present moment from comparison / contrast with the pandemics of 1957-8 and 1968. It seems all the interest has focused on 1918-19.

I’m just now learning about these mid-20th century pandemics. I’ve been reading and consulting the sources referenced on this this CDC site.

* In 1968, I see, for example, “The estimated number of deaths was 1 million worldwide and about 100,000 in the United States. Most excess deaths were in people 65 years and older.”

* In 1957-8, the virus was “first reported in Singapore in February 1957, Hong Kong in April 1957, and in coastal cities in the United States in summer 1957. The estimated number of deaths was 1.1 million worldwide and 116,000 in the United States.” From further reading, it seems this strain of flu was not often fatal in children, but was very dangerous for the elderly, those with other health problems, and for pregnant women.

The 1957-58 virus was known as the Asian flu, while the 1968 version was called the Hong Kong flu. I was a college student in 1968, and I have no memory of any widespread concern about the flu virus at that time. Certainly no one proposed shutting down schools, businesses, travel, and so on.

We don’t need to go that far back in time for another parallel. Just two years ago, the 2017-18 flu season, that year’s virus killed an estimated 62,000 Americans. Based on news reports, I believe the CDC originally estimated the death toll at 80,000 and later reduced that estimate to 62,000. Moreover, if we look at the numbers globally rather than focusing only on the U.S., the average seasonal flu virus kills around 468,000 people. This is a simple chart that I have updated from time to time. From the left, the bars show the average worldwide fatality total for seasonal flu, per the WHO; the COVID-19 global death total, per WHO; the number killed in the U.S. by the flu virus two years ago, per CDC; and this year’s U.S. COVID-19 total, per CDC.

According to the WHO, we are now a little over half-way to an average flu season. My guess is that the global COVID-19 count will, in the end, modestly exceed the average for seasonal flu. The U.S. numbers are not necessarily an apples-to-apples comparison. The 2017-18 total is an estimate, while the COVID-19 figure doesn’t purport to be the total of those actually killed by the virus–headlines to the contrary notwithstanding–but includes an unknown number who died from something else (e.g., cancer) and happened to have coronavirus symptoms when they died. So those totals aren’t comparing apples and apples, more like comparing an orange and a pear.

Still, the conclusion is reasonably clear. What is unprecedented about the Wuhan virus is not the lethality of the disease, but rather the reaction to it by many of the world’s governments.

This is as good a time as any to add an international comparison. This chart shows the per capita death rates, in fatalities per million, for the 12 countries with the highest such rates. For now, the U.S. rate compares favorably to those in the European countries that have been hit hard by the virus. I don’t know, however, whether countries follow the same protocol in counting COVID deaths. My guess is that they don’t, and that some countries only count fatalities actually caused by the disease.

I speculate further that the U.S. rate is lower than the major European countries mostly because the disease arrived here later. In the end, my guess is that, allowing for random variation, different methods of counting fatalities, and demographics (i.e., the percentage of elderly people in the population), countries will generally have similar fatality rates, and varying methods of “fighting” the virus will be found to have made little difference. But that is only a guess.

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