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Andy Larsen: How well does the vaccine work against omicron? Here’s the real-world data.

Numbers reveal key benefits to vaccine boosters in fighting infection, severe illness and death.

Rick Egan | Tribune file photo) Covid vaccinations provided by the Salt Lake County Health Department at the Rancho Market parking lot on Redwood Road, on Thursday, January 6, 2022.

Often, we have to communicate shaded ideas in a world where it’s just easier to remember ideas in black or white.

And this creates a problem: most people consider themselves better wordsmiths than number crunchers. And yet, sometimes, in communicating changing or proportional ideas, words just aren’t the right tool for the task. Numbers are.

Nowhere is this more obvious than in a large portion of the public’s misunderstanding — accidental or otherwise — of the coronavirus. That the omicron variant is “more mild” than previous variants is taken to mean that “omicron is mild.” That masks prevent some amount of transmission, but not most of it, is taken to mean that masks don’t work. And when it’s said that the vast majority of people survive the virus, many take that to mean that they’re okay to live with vast impunity.

So when people read articles on vaccine efficacy, and see that the vaccine is “less effective” against omicron, many take that as “the vaccines are ineffective.” It’s just too easy to subtly shift the meaning of words and phrases, even unintentionally.

Well, I want to try to nail that down. Using real-world case, hospitalization, and death counts, I want to show you the efficacy — and yes, sometimes, the lack thereof — of our current vaccines against omicron.

First, here’s the Utah data. These represent the weekly averages of cases, hospitalizations, and deaths per 100,000 Utah residents since the beginning of vaccines. If you’re online, you can scroll your mouse or finger and look at the exact numbers for each week.

The trend is clear, and it’s a continuing one: vaccinated people fare far, far better in this pandemic than unvaccinated people. Over the last 28 days, for example — which will include a mix of omicron and delta — unvaccinated people are 2.4 times more likely to be infected, 8.9 more likely to be hospitalized, and a whopping 16.2 times more likely to die than vaccinated people. Even in just the most recent weeks, in which omicron is estimated to be about 90% of cases, we still see massive gaps.

For the graphs above, “vaccinated” means at least one dose of Johnson & Johnson, or at least two doses of Pfizer or Moderna. Boosted people are included.

So how does getting a booster dose of the vaccine change the numbers? Well, unfortunately, we don’t have Utah data on boosted versus vaccinated versus unvaccinated. I’m not sure why the Utah Department of Health doesn’t keep track of this — maybe it’s because only 22% of Utahns are boosted? Regardless, I wish they would.

But we do have numbers from other countries, again showing real-world data in boosted vaccine efficacy.

In particular, the United Kingdom has done a really good job of data collection throughout the pandemic. What their data shows is that, yes, omicron is making the vaccines significantly less effective in protecting against infection. Take a look at this graph. On the left is how vaccine efficacy has declined hugely for people who had two Pfizer doses long ago against omicron; on the right side is how boosted people are faring so far.

A graph from the United Kingdom's Health Security Agency about the efficacy of two doses of Pfizer's vaccine (BNT162b2) vs. when it is boosted (with either Pfizer or Moderna). (https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1045329/Vaccine_surveillance_report_week_1_2022.pdf)

In the U.K.’s data, the efficacy against having symptomatic sickness after having two doses of Pfizer over 6 months ago is near zero — not great at all.

But there’s good news: it helps significantly if you’ve been boosted. That number goes to about 50-60% if you stuck with Pfizer, or about 70% for those who mixed and matched.

There’s more to the story, too. The vaccine also serves to make infections significantly weaker when they do happen — especially for boosted people. The U.K.’s data shows that getting two doses of the vaccine offers a 51% reduction in hospitalization likelihood, while three doses means about a 68% reduction.

And remember: these numbers stack. This table explains the situation: Boosted people get doubly protected — not only are they less likely to get sick, if they do happen to get sick, they’re also less likely to go to the hospital.

What we don’t have great data on from anywhere in the world is whether or not the vaccines actually triply (speaking of words, is triply one of them?) protect us against omicron. Are those rare unfortunate souls who are boosted but end up going to the hospital due to omicron protected against death when compared to their unboosted hospitalized counterparts? While I’d like data on that, I understand that it’s difficult to find the sample size for good data ... after all, boosted people simply are rarely hospitalized for the disease!

But the above numbers also point to another frequent pitfall — the outsized value we place on anecdotal evidence. Take that 63% efficacy number above, which represents the amount of time boosted people are protected against omicron sickness. That’s pretty good — more effective than any flu vaccine has been in the last 15 years!

It still means that, in our current environment, most people are going to know someone who was boosted and got sick anyway. As a result, many folks will take “the vaccine didn’t work for Mary,” simplify it, and think that the “vaccines don’t work.”

So let this article serve as a salve against that type of thinking. When you see someone use an anecdotal argument to make a case against vaccines in our omicron times — or worse, to say that “less effective” means “ineffective” — show them these graphs. Show them these figures.

When an argument goes monochrome, paint by numbers.

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