Monday, January 17, 2022

Let Me Help You with the Covid-19 Risk Assessment


Back before I retired I did risk assessments all the time, although they were highly specialized and unrelated to health issues.  Still, I'm familiar with the techniques.  What are the odds of various outcomes, what are the stakes of those outcomes.  Then balance the numbers.

Feel free to skip to the conclusions.

Covid Percentages


What's the percentage of the (US) population who's been infected?  (I'm generally going with US numbers here.)
⦁    31% estimated as of about a year ago
⦁    Source: https://www.publichealth.columbia.edu/public-health-now/news/one-three-americans-already-had-covid-19-end-2020
⦁    Also: https://directorsblog.nih.gov/2021/09/07/covid-19-infected-many-more-americans-in-2020-than-official-tallies-show/
⦁    As of the end of last month, 57,898,239 cases reported from a population of 333,961,250 = about 17% (asymptomatic and mild cases won't always be reported)
⦁    Source: https://www.cdc.gov/coronavirus/2019-ncov/covid-data/covidview/index.html
⦁    And: https://www.worldometers.info/world-population/us-population/

Of those infected, what's the percentage chance of severe symptoms?
⦁    1 in 6, around 17%
⦁    Source: https://www.webmd.com/lung/covid-19-symptoms#:~:text=Most%20people%20will%20have%20mild,diabetes%20or%20heart%20disease

What's the percentage chance of dying from Covid-19?
⦁    859,356 dead in a population of 333,961,250, or just over 2.5%
⦁    Source: https://www.statista.com/topics/6084/coronavirus-covid-19-in-the-us/
⦁    And: https://www.worldometers.info/world-population/us-population/

Vaccination Percentages


What percentage of those receiving vaccines had a reaction?
⦁    2.5% had an allergic reaction
⦁    Source: https://www.massgeneral.org/news/press-release/Real-world-data-reveal-risks-of-allergic-reactions-after-receiving-covid-19-mrna-vaccines
⦁    0.6% in the vaccine group and 0.5% in the placebo group had a severe response.  (Serious adverse events were defined as any untoward medical occurrence that resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, or resulted in persistent disability/incapacity.)
⦁    Source: https://www.cdc.gov/vaccines/covid-19/info-by-product/pfizer/reactogenicity.html
⦁    Thrombosis with thrombocytopenia syndrome (TTS) after the Johnson & Johnson vaccine was 57 out of 17,200,000 doses (.0003%)
⦁    The chance of Guilain-Barre Syndrome may be (based on preliminary reports) higher, 283 of 17.2m (.0016%)
⦁    Source for both: https://www.cdc.gov/coronavirus/2019-ncov/vaccines/safety/adverse-events.html
⦁    Myocarditis and pericarditis (heart inflammation): 518 cases as of about six months ago out of (at that time) 158m fully vaccinated: .0032%
⦁    Source: https://www.healthline.com/health-news/vaccine-side-effects-vs-covid-19-damage-theres-no-comparison

What percentage of those vaccinated will get sick from Covid-19 anyway?
⦁    1 in 5,000 = .02%
⦁    Source: https://www.hopkinsmedicine.org/health/conditions-and-diseases/coronavirus/breakthrough-infections-coronavirus-after-vaccination

What percentage of those vaccinated have died from the vaccine?
⦁    3 out of 187,200,000 vaccinated (.00000016%)
⦁    Source: https://covid-101.org/science/how-many-people-have-died-from-the-vaccine-in-the-u-s/
⦁    Note: 187.2m vaccinated out of 333,961,250 population = 56%

Infection by Status


For the population of Washington state, at least:
⦁    People ages 12-34 are 2x more likely to be infected if unvaccinated, 10x more likely to be hospitalized
⦁    People ages 35-64 are 3x more likely to be infected if unvaccinated, 14x more likely to be hospitalized
⦁    People age 65+ are 6x more likely to be infected if unvaccinated, 13x more likely to be hospitalized
⦁    Source: https://www.doh.wa.gov/Portals/1/Documents/1600/coronavirus/data-tables/421-010-CasesInNotFullyVaccinated.pdf

Conclusion I


Assessing risk means balancing the various odds against the stakes.  Here are your stakes, which are straightforward: death or severe illness/reaction.

Here's your odds:
⦁    You're 2 to 6 times likely to be infected if unvaccinated
⦁    Of those infected, about 17% have gotten severe symptoms, 2.5% died
⦁    You're 10 to 14 times more likely to be hospitalized if you do catch it and you aren't vaccinated
⦁    Of those vaccinated, .6% had a severe response to the vaccine, compared with .5% of those given a placebo.
⦁    Of those vaccinated, .00000016% have died
⦁    2.5% dead from Covid is 15,625,000 times more likely than .00000016% from vaccination

For an alternate perspective:
⦁    3 dead from vaccination, as noted above
⦁    11 or so people die every year from spider bites (Source: https://faunafacts.com/spiders/yearly-deaths-from-spider-bites/)

There's your risk, and it's not that hard to assess.

Do the math.  Get vaccinated.

Conclusion II


No numbers here, just the way infections work and how this one works.

Very young children still can't be vaccinated, vaccines are less effective for those with aging immune systems, and may do very little for people with compromised immune systems (like cancer patients, or people with organ transplants or autoimmune disorders such as lupus or Crohn's disease).

You may like your chances because you're young and healthy.  But are you willing to risk infecting those less fortunate?  Are you going to throw your grandparents and all those preschoolers under the Covid bus?

Worse, keep in mind that viruses are always mutating, but generally only when they reproduce.  The bigger a pool of infected people, the more they're reproducing, and the more mutations we will get.

Delta was deadlier, omicron more everpresent.  Heaven knows what the next will be like.

Even if you figure you won't get severe symptoms or die, do you want to help the next Covid variant come along?

Do the right thing.  Get vaccinated.

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