I’ve seen many articles on the mortality rate of Covid-19, either nationally or globally, but what I haven’t been able to find is the mortality rate of the Omicron variant for the county I live in, which is a much more relevant piece of information.
Now before we get into what I found, here are some caveats:
- I am not a doctor.
- I am not a virologist.
- I am not a statistician.
- All of the data I use is publicly available from NCDHHS.
- I chose Wake county because that’s where I live, and it looks different from many other counties in NC because the vaccination rate is much higher here, with 81% of all people having at least one shot.
My methodology was very simple. Starting 27 Sept 2021 and ending 22 March 2022 I add up all the reported deaths, and divide that by the number of reported cases over the same period, a time range that should contain only the Omicron wave.
Now, you may object to that methodology on several grounds:
But deaths occur on average 18 days after the onset of infection: True, so in theory I could drop the first 18 days of deaths, and drop the last 18 days of infections, but in reality cases and deaths were very low at those times and it wouldn’t materially affect the results.
But testing is poor: True, which means that this mortality rate is only an upper bound, as you point out if more tests were reported then the mortality rate would go down from what I calculated.
But you count people that died with Covid and that died from Covid: Again, this is true, and since the number of deaths of people just from Covid would be a smaller number, this again means the number I calculated is only an upper bound.
Many cases of Covid-19 are asymptomatic: Yes, and again, this means that the number I calculate here is only an upper bound, and is more likely even lower.
But what about long Covid: I wasn’t interested in calculating anything about long Covid, but this Nature article might be interesting to read: Long-COVID symptoms less likely in vaccinated people, Israeli data say
What about Alpha and Delta?: They sure seemed to have higher mortality, but as they have been supplanted by Omicron aren’t really relevant to me right now.
So, with all the out of the way, what did I find?
Between 27 Sept 2021 and 22 March 2022 in Wake County, NC there were 168,324 cases and 197 deaths, which gives us a mortality rate of 0.12%. But please remember all my caveats above that this should be taken as an upper bound, and the true value is likely lower.
How does that compare to, say, the season flu? The CDC estimates that in 2017-2018 flu season that 51,646 people died with a total of 41,043,550 symptomatic illnesses, which is a mortality rate of 0.13% for the entire U.S.
For addition comparison the numbers from the 2015-2016 flu season are 22,705 deaths for 23,504,319 symptomatic illnesses, which gives us 0.095%, again for the entire U.S.
You aren’t quite comparing the same things: True, CDC estimated symptomatic illness from the flu is different from the number of people that tested positive for Covid-19, and I’m comparing Wake County numbers versus national numbers, but what I’m hoping for here is a rough comparison, like are they with 2x of each other, or more like 10x of each other, and I’m pretty satisfied that as of right now the flu and Omicron mortality rates are in the same ballpark for my county, which is pretty amazing that in just two years we’ve been able to get the virus down to that level with a combination of vaccinations, herd immunity, and theraputics.
Obviously your mileage, and your county, may vary.