Warning - Nerd Alert 🤓.
Okay, this is going to be a bit dense in terms of data, but I did not want anyone to accuse me of making things up. And I think it is ESSENTIAL to answering the following question so people FINALLY understand why so many of us keep saying COVID-19 is a big f-ing deal:
"What's the big deal about COVID-19? The flu kills WAY more people every year!"
I am not an expert in infectious disease, nor am I an epidemiologist. But I am an intelligent human being, and I wanted to be able to put into words why COVID-19 is such a big deal. Then my friend posted this:
HOWEVER, I did not want to look at this article and just regurgitate it. I wanted to do some fact checking on my own because journalists are not scientists. So I wanted to confirm the data presented in this article.
So I went to the most legitimate source: the CDCs website.
I have broken down their explanation of methods to determine how they calculate the huge numbers we all see when describing flu-related deaths, and why using that number as an argument for why COVID-19 is "no big deal" is totally off-base. If my interpretation is incorrect in any way, my apologies ahead of time, and I would be happy to correct any errors if so!
Let's start with the CDCs FAQ section - https://www.cdc.gov/flu/about/burden/faq.htm
This is an extremely important question to ask:
Does the CDC know the exact number of people who die from seasonal flu each year?
The CDC does NOT know exactly how many people die from seasonal flu each year.
The reasons (summarized here): 1. If over the age of 18, states are not required to report individual flu-like illnesses or death. 2. Flu is infrequently listed on death certificates who die of complications related to it. 3. Many flu-related deaths occur 1-2 weeks after initial infection due to either a. secondary bacterial co-infection (eg bacterial pneumonia) or b. aggravation of a preexisting chronic disease (eg congestive heart failure, COPD). 4. Many people who die from flu-related complications are not tested for flu or flu may no longer be detectable if seek care later. 5. Some commonly used tests to diagnose flu can provide false-negative results (ie they have the flu but the test says they don't)
This is why the CDC uses statistical and mathematical models to ESTIMATE the annual number of flu-related deaths. That estimate is MUCH HIGHER than the flu-related confirmed deaths. And this estimate is not accurate until 1-2 years later once all data can be collected for that given season; initial estimates use previous seasons flu-testing data.
So how does the CDC estimate these deaths?
The photo I posted is from the CDCs website, and I will do my best to explain it in the following section - https://www.cdc.gov/flu/about/burden/how-cdc-estimates.htm
Explanation: 1. Reported rate of hospitalization: this is the hospitalization rate for people who actually tested positive for flu per the Influenza Hospitalization Surveillance Network (FluSurv-NET), a collaboration of multiple entities including the CDC, and includes hospitals that serve about 9% of the population.
Now correct for under-detection: 2. Adjusted rate of hospitalization: this is determined by taking the reported rate of hospitalization (see 1 above) and adjusting it for the number of people hospitalized for any respiratory illness who: a. were actually tested for flu and b. under-detection of flu by the tests used at those hospitals in FluSurv-NET (ie patient tested negative but actually had the flu). The rates are adjusted based on age as well.
Now extrapolate to US population to determine total hospitalized (since only using 9% of the populations data). Once done, the following can be calculated (symptomatic illness but not death is not relevant to our discussion): 3. Calculated (ie estimated) deaths, and subsequently deaths:hospitalizations ratio, can be determined once we figure out two factors: a. In-hospital deaths: confirmed flu-associated deaths in hospital per FluSurv-NET adjusted for the same factors as 2a&b above b. Out-of-hospital deaths: examine death certificates and causes of death [pneumonia/influenza (P&I), other respiratory and cardiac (R&C), or causes other than] since deaths related to the flu may not be listed as flu, and then look at FluServ-NET's data at the mixture of P&I, R&C, and other deaths
Phew! That was a lot of information. I wanted to summarize the info on the CDCs website but not make it too simplistic.
But if NONE of it made sense or elicited some major 🙄🙄🙄🙄🤷🏽♂️🤷🏽♂️🤷🏽♂️🤷🏽♂️, no matter.
The two major take-home points?
1. The CDCs methodology to determine flu-related deaths is COMPLICATED.
2. The number of CONFIRMED flu-related deaths in the US for a given year is always MUCH LOWER than the models 1-2 years down the road project.
Now let's compare the data from the swine flu (H1N1) to COVID-19 in the first 66 days (the Washington Post article was INCORRECT in the data they quoted, hence fact-checking, so I updated it):
1st documented US infection of H1N1 (April 15, 2009) - https://www.cdc.gov/…/pandemic-…/2009-pandemic-timeline.html
66 days later (June 20, 2009) - https://www.cdc.gov/h1n1flu/updates/062609.htm: 27,717 confirmed and PROBABLE cases (meaning it meets the case definition but is NOT laboratory-confirmed), 127 deaths
1st documented US infection of COVID-19 (Jan 21, 2020) - https://www.cdc.gov/…/p0121-novel-coronavirus-travel-case.h…
66 days later (March 27, 2020) - https://www.cdc.gov/…/2019-n…/cases-updates/cases-in-us.html: 103,321 CONFIRMED cases, 1668 deaths
Yes, there was a second wave of infections in the fall for H1N1, but we don't know yet if the same will be true for COVID-19. Ultimately, these were the estimates the CDC determined for H1N1 in the US from April 12, 2009 to April 10, 2010 - https://www.cdc.gov/…/pandemic-reso…/2009-h1n1-pandemic.html:
60.8 million cases, 274,304 hospitalizations, and 12,469 deaths.
In ONE YEAR per their model.
We're ONLY 2+ months into COVID-19 and won't be able to project its true impact till probably 2022 because we have no previous data. And we are FAR ahead of H1N1s impact in the same time frame. And as a result, we are running out of resources.
Do you see now why we CAN'T compare the numbers we see with COVID-19 to influenza or swine flu?? THE DATA IS TOTALLY INCOMPLETE.
It's comparing apples to peanut-butter and jelly sandwiches.
COVID-19 is spreading much quicker and is more lethal than H1N1 at its beginning stages. Hence why the CDC is taking this so seriously and the projected models for COVID-19 are frightening.
TAKE THIS SERIOUSLY, PEOPLE.
And if the models end up being completely off, no one will be happier than me, and I'll eat crow and be Mr. Doom-and-Gloom. But if we use past pandemics as a reference, such as H1N1, this could be a whole lot worse than what many of us want to believe.
Okay, enough for tonight. I'm tired. Time to go to sleep. I hope this was helpful and not TOO painful.