Covid is over 500 times deadlier than the flu
Debunking the notorious talking point that claims Covid is nothing more than a bad flu
As we head into the second winter of the Covid era and with the hyper-transmissible Omicron variant now on the loose worldwide, many countries are bracing themselves for what is likely to be yet another deadly wave of a virus that has now officially killed over 5 million human beings. Despite these grim statistics, the idea that Covid is no worse than the flu remains widespread among Covid-skeptics and the anti-mask/vax/lockdown crowd (Covidiots for short). If Covid were indeed not much worse than the flu then surely there would be no need for social distancing, lockdowns, or vaccine mandates. Alas, Covid-19’s true deadliness is not just much worse than what the Covid skeptics think. It’s worse than what the rest of us think too.
The myth that Covid was not significantly deadlier than the flu emerged at the start of the pandemic, but early studies were already showing a disease that was considerably deadlier. A February 2020 study from Chinese patients that was widely quoted at the time revealed that Covid-19 had a case-fatality rate of 2.3%. The similar figure for the US 2019-20 flu season was just 0.6% according to the CDC. Later studies have only reinforced this. A December 2020 study gave Covid-19 a 2.82% mortality rate, with the data also showing a much higher rate of hospital deaths relative to the flu (16.9% vs 5.8%) and almost double the lengths of hospital ICU stays. Still, in our heuristically-impaired minds, a mortality rate of 2.82% might not seem particularly high, especially comparing with other coronaviruses. SARS kills one of ten people it infected, and the mercifully rarer MERS kills one out of three.
Unfortunately, SARS-CoV-2’s superpower is not its ability to kill but rather its ability to spread. This new coronavirus has an absurdly long incubation period of up to 14 days which facilitates transmission. For comparison, the flu typically has an incubation period of just 1-4 days (average of 2). Asymptomatic transmission, estimated at around 17-20%, also contributes to this spread. This figure is considerably lower compared to figures of around 80% estimated initially but given the sheer number of infections is still a huge number in absolute terms.
As a result, the transmissibility of SARS-COV-2 as measured by its R0 or “R nought” number (the number of secondary infections caused by every new infected person assuming no immunity) was estimated at 2-3, compared to the seasonal flu’s 1.3. But that’s nothing compared to the newer variants. The Alpha variant first identified in the UK in late 2020 was estimated to have an R0 of 4-5. The Delta variant, originally from India and currently the dominant strain in most parts of the world, has an R0 of around 5-9.5 and can easily spread even among vaccinated people, though thankfully the vaccines prevent severe disease. We still don’t know what the R0 of Omicron is but we do know it is even more transmissible than Delta.
Fatality rates may capture the public’s attention and fears but in practice, it’s transmissibility that really determines how deadly a virus is over time. It matters little for a disease like MERS to kill one out of three of its hosts if it can only spread to just over 2,500 people in the decade since its discovery. SARS-CoV-2 has spread to over 250 million people in a year and a half and that’s likely a gross understatement since it doesn’t take into account unrecorded cases as well as undercounting the pandemic’s first wave when testing was not as widespread.
Comparing flu seasons
It should be obvious why comparing Covid-19 with previous flu seasons is conceptually problematic. The seasonal flu is not a virus against which we take the containment measures we have imposed during the Covid pandemic and thus we are comparing two entirely different transmission environments. Covidiots who consistently push the “not much worse than the flu” narrative completely fail to account for this rather important fact, instead using the flawed logic that we shouldn’t impose restrictions simply because the headline mortality rate and death tolls are not that much higher. Transmissibility matters.
Thankfully, we now have a flu season (2020-21) that has coexisted with the Covid pandemic to make adequate comparisons with, given that both viruses will have operated in an identical transmission environment. And the data reveals a mind-boggling fact. Covid-19 isn’t just slightly worse than the flu: it’s 543 times worse than the flu. You read that right, 543 times. During the 2020-21 flu season, estimated by the Center for Disease Control (CDC) to run between the 40th week of the first year (roughly the start of October) and the 20th week of the second year (towards the end of May), Covid-19 killed 384,717 people in the US.
How many did the flu kill during this same period? Just 708.
There is an important caveat to the 708 flu deaths figure. Influenza is a disease that frequently kills people (particularly older people) outside of a hospital, where these deaths aren’t registered as such by a doctor and thus tallied by the National Center of Health Statistics (NCHS). In medical terminology, this is known as “coding” and the CDC recognizes that coded flu deaths are grossly understated. As a result, the CDC uses a mathematical model to estimate the annual burden of flu and come up with an estimate of the actual number of deaths. In the 2019-20 season, for example, there 9,241 coded flu deaths in the US but the CDC estimate showed a much higher tally of 20,342. With respect to recent flu seasons, the 2017-18 has been by far the deadliest, with 15,415 coded deaths and 51,646 estimated deaths.
This is important because the 708 figure is undoubtedly an understatement of the actual number of flu deaths during the 2020-21 season. However, the anomalous nature of this season means that the model used for previous seasons will be thrown off considerably to the point that it is likely to be useless without major tweaking. This is why we’re not likely to see a CDC estimate for the 2020-21 flu season anytime soon. But even so, it would be unfair to compare any eventual estimate with the coded Covid-19 deaths. Estimates of excess deaths around the world have shown that Covid-19 is also grossly underreported and this has not been the exception even in the US. For example, a May 2021 paper estimated that US Covid-related excess deaths were 1.59 times higher than the official Covid death tally. There is no escaping that by any metric used, Covid deaths exceeded flu deaths by an astronomical margin.
No normality (yet)
These shocking numbers should immediately render the Covid-skeptic and anti-lockdown arguments moot, and justify the measures that many governments undertook to contain this virus however extreme many people have perceived them to be. Looking at the chart, it is frightening to imagine the counterfactual of just how high Covid deaths would have been if we had simply let the virus run its course like we do in every other flu season.
While the mass vaccination of Western countries suggests that even a new winter Covid wave will be far less deadly than the previous one, especially considering the early evidence that Omicron is milder than Delta, the return of our old friend influenza must also be weighed in. Absent the social distancing measures that we had a year ago, there is nothing to prevent the flu from making its comeback, and perhaps even deadlier than ever: many people in Britain over the past few months have reported catching a ‘super cold’, likely because our bodies stopped getting used to it. Considering that the flu is considerably worse, you can imagine the prospect of having to deal with Covid and a ‘super flu’ in the months ahead.
What we now know of the comparative deadliness of Covid and the flu during a season in which both viruses spread under identical conditions should be the best warning sign against complacency. A virus that is 543 times deadlier than the flu has to be taken with all the seriousness it deserves, all the more considering that the flu will be hanging around with it.
Did you like this article? Follow me on Twitter at @raguileramx and on YouTube at ProgressumTV. You might also like my book, The Glass-Half Empty: Debunking the Myth of Progress in the Twenty-First Century (Repeater Books, 2020).