Thursday, January 21, 2021

How deadly is COVID-19 to me, and people like me?


Is going out of your house for anything other than absolutely life-critical reasons comparable to going to an active shooter location? This is the claim made recently to me by a colleague. The same person tried to emphasize how awful the risk is by saying that I was 50 times more likely to die from COVID-19 than from influenza. More generally, how worried should someone of my age and health be about going to shop for groceries, getting take-out food, or other regular activities that could be avoided but that don’t involve getting close to unmasked people? And how should be most usefully frame that risk.

The numbers in this piece are for people like me. I’m male in the 55 to 64 age group with no major medical issues. I’m white, not desperately poor, not diabetic, not obese, and do not have reduced kidney function, stroke, or dementia, nor any neurological conditions. I do have other medical issues, but they have no bearing on my COVID risk.

In discussing how to communicate the risk to others, a colleague made two comparisons: The risk of dying from COVID as compared to dying from influenza; and the act of going out of your home for anything other than absolutely survival-critical reasons as being like entering an active-shooter location. Let’s take the flu comparison first.

My interlocutor said that males of our age (we are both between 55 and 64) are 50 times as likely to die from COVID as from flu. If you look at the CDC’s numbers for 2020, that will appear correct. Making that comparison is misleading because it would be natural to assume he wants you to compare the risk of dying from COVID to the usual risk of dying from fly. But flu killed only about a quarter as many as it typically does. So, the real number is that, if you catch flu, you are about 12 more likely to die of it compared to your fatality rate if you catch COVID.

The 50:1 ratio came from a June 23, 2020 article in BusinessInsider.

Other sources given a lower ratio even than my corrected 12:1. According to the October 2020 piece here: for males, 55-64, they are 5.97 times more likely to die of COVID than of flu.

between the beginning of February and January 2, 2021, there were around 318,786 deaths with confirmed or presumed COVID-19. There were also 8,846 fatalities involving influenza, which had pneumonia or COVID-19 also listed as a cause of death. If I were to use the same tactic by selecting a different year for flu, let’s say 2017-2018, I could change the picture greatly. That was an unusually bad year for influenza. According to the CDC, the overall burden of influenza for the 2017-2018 season was an estimated 45 million influenza illnesses, 20 million influenza-associated medical visits, 800,000 influenza-related hospitalizations, and 61,000 influenza-associated deaths. That’s 61,000 compared to 2020’s 8,846. I could then say that you are only 6.9 times more likely to die of COVID compared to flu. 

You could also compare the Flu vs COVID hospitalizations vs. deaths. As of 01/20/21:

Flu: 458,320/37,239 = 8.1%

COVID: 5,729,000/486,965 = 8.5%

So, risk of dying from COVID after hospitalization is almost the same as for flu.

Similarly, a study published in the December 15, 2020 BMJ put the death rate among COVID-19 patients at 18.5%, while it was 5.3% for those with the flu. Those with COVID were nearly five times more likely to die than flu patients.

But none of these comparisons to flu mortality is particularly helpful.

The relevant comparison with flu is not the chance of dying if you have flu, it’s the chance of catching flu/the chance of dying of flu. I don’t concern myself even a little about the mortality risk from flu. It’s so low that I find it an unhelpful point of comparison. (But I do get my flu shot every year, as early as possible, since non-lethal flu is nasty, and the shot costs me nothing other than a few minutes.) For males in my age group, flu is not even listed among the top 10 causes of death.

The active-shooter risk comparison

This is even less helpful than the comparison to flu mortality. I don’t happen to know the mortality risk of every type of event. I estimated it as higher than it is. (In so far as there are reliable numbers and definable groups-at-risk.) So, my conversant jumped on that as supporting his point. Except it didn’t. My response (the rational one) was NOT to increase my estimate of the risk of dying from COVID-19; it was to reduce my estimate of dying should I somehow find myself in an active shooter situation. It caused me to lower my (already very minor) concern about getting shot.

Even more so than for influenza, the relevant comparison is not the chance of dying in an active shooter situation. It’s the chance of getting into an active shooter situation/the chance of dying in such a situation. We are ALL in an active COVID situation! (Unless you are a very strict hermit.)

Most sensible measure of risk of dying from COVID-19

What is the most reasonable and useful measure of risk of dying from COVID-19? Again, to keep the discussion manageable, I’m focusing on the absolute annual level of risk for someone like me. A good first approximation puts the risk at 2.8%. But MY risk – and the risk to other males my age who also lack risk factors – is less. A more accurate number (which is hard to ascertain) would be much lower since I lack any of the risk factors. But here are the current stats on raised risks for each of the major risk factors that I lack, other than being male. [Source:]

The major factors increasing the mortality risk from COVID-19 are:

1.   High deprivation (low socioeconomic status)

2.   Male

3.   Obesity

4.   Uncontrolled diabetes

5.   Being black or Hispanic

6.   reduced kidney function

7.   stroke or dementia

8.   neurological conditions

The 2.8% fatality risk already includes being male, so let’s set that aside. When it comes to economic deprivation, “The magnitude of risk amplification [for COVID-19] is 0.41 and 0.23 for Quintiles 5 and 4, respectively.”

As for ethnicity, Asians have a slightly lower risk compared to white. Blacks have 1.48 times the risk. Surprisingly, this sources does not break out the risk for Hispanic people. That’s stunning, given the incredibly high proportion of all cases accounted for by Hispanics in Southern California.

Obesity: Risk increases from 1.40 to 1.92 depending on how obese you are. (I saw no definition of Type I and Type II obesity.)

Diabetes: 1.31 (controlled) to 1.95 (uncontrolled).

Reduced kidney function: eGFR 30-60: 1.33. eGFR <30: 2.52.

Stroke or dementia: 2.16.

Neurological conditions: 2.58.

Since I’m not clear on the overlap between these factors, I’m not going to try to compute an overall risk for people of my age and condition. But it’s very clear that the risk is much lower than 2.8%. My WAG is that my risk is around 1%. That’s very close to my risk of dying in any year from other causes in non-COVID times. (Obviously, that’s in addition to my normal background risk.)

To further keep my risk in perspective (and yours, with appropriate adjustments), I consider my normal risk of dying in a non-COVID year. I don’t have figures adjusted for multiple factors as above. I only have the average for a male my age. I’m about to turn 57. My death probability is given as 0.9156%. Interestingly, that’s awfully close to (probably higher than) my best current guess for my COVID-19 mortality risk.

My estimated mortality risk for COVID is probably around 1% (with fairly large error bars).

If you are not a male of my age group and health, I hope exercise helps you to estimate your mortality risk from COVID-19. Of course, where you live should certainly have a bearing on your evaluation of the risk. Not only the mortality rate in your state and county, but also the level of stress on medical facilities.

Also, mortality risk is far from the only consideration. Lung damage and “long COVID” actually concern me more than my own mortality risk. The evidence is too early to estimate risks of these, but it looks like a major problem.

Even the most intelligent people can get sucked into the pull of fear. It’s a huge problem in our thinking today. It helps to put risks in context by breaking them down and by comparing to other baselines, such as regular mortality rates.

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