Vaccine Hesitancy and Odds of Going to the Hospital

In the great push to get everybody jabbed with the experimental COVID vaccine, people in the wait-and-see camp have been painted as conspiracy theorists and anti-science morons--the sort of people you'd see at the recent Redneck Rave where 15,000 people came and some ended up impaled, choked or badly cut. Dozens were charged with crimes. Won't it be interesting to see Edmonson County, Kentucky's COVID stats in a few weeks. Surely the local hospital will be full of rednecks, and not just to have fingers sewn back on...right?

Use this, plus your region's dashboard, to calculate your odds. Photo from Pixabay.

Maybe not. Humans are inherently bad at estimating odds. Several news outlets report that 99% of COVID patients in the hospital are unvaccinated, so does that mean you're almost a hundred times more likely to end up in the hospital if you haven't had your shots? Not quite. Looking only at hospitalized people rather than the whole population is relative risk. The relative risk reduction of symptomatic cases in the vaccine trials ranged from about 70% to 95%, which isn't that far off from what the news reports about COVID cases in hospitals. But if you don't currently have COVID, you're probably more interested in your absolute risk. The vaccine manufacturers' own trials showed only about a 1% reduction in absolute risk of getting symptomatic COVID. In other words, for study group of 200 (100 who get the vaccines and 100 who get a placebo), only 1 more person in the placebo (control) group would get sick. 

We can calculate real-world absolute risk reduction of being hospitalized with COVID here in Indiana--which is next door to Kentucky, coincidentally. Close to three million people out of 6.5 million are fully vaccinated. Around 40 people per day are being admitted to the hospital for COVID, according to our dashboard. If we extrapolate that to two months (the length of the vaccine studies), that amounts to 24 vaccinated people and 2,376 unvaccinated people ending up in the hospital. Dividing by 3 million and 3.5 million, respectively, and subtracting the results gives us a difference of 671 per million. That's less than one in a thousand. Looking at it another way, you'd have to vaccinate 1,500 people to prevent one hospitalization over the next two months.

So why the higher rate of unvaccinated people in the hospital than what showed up in the studies? A couple of possible reasons. The studies looked at symptomatic COVID cases, not hospitalizations. Then there's the healthy user effect. People taking the vaccines might also be taking other steps to reduce their risk of getting COVID. Another is socioeconomics. Some researchers from the University of Pittsburgh and Carnegie Mellon University conducted a survey on vaccine hesitancy. Here's something they found:

Workers in some occupations were more reluctant than others to take the jab. Hesitancy ranged from 9.6% among educators and people in life, physical or social sciences to a high of 46% among workers in construction, oil and gas extraction and mining. Hesitancy was nearly as high among workers in installation, maintenance, repair, farming, fishing or forestry.

In health care fields, pharmacists were the least hesitant at 8.5%. The highest hesitancy, 20.5%, was among medical assistants, emergency medical technicians and home health, nursing, psychiatric or personal-care aides.

The highest portion of the vaccine hesitant was among people who can't Zoom into work for one thing. The have to show up and in some cases have close contact with people. For another, they're in physically demanding jobs that might put them around unhealthy chemicals--and the human body has a limited ability to repair itself. And my experience (my father worked construction) is that blue-collar people are less fussy about what they eat and whether they smoke than desk jockeys are. Again, it's the healthy user effect. These things might make people more likely to contract and get ill from COVID.

There's an impression that the hesitant believe in wild stories like microchips in the vaccines or that they simply don't want to be told what to do. But the study found that the main concern was side effects. Many of the unjabbed are people in dangerous jobs where things absolutely, positively have to work in the real world--and they've found that recommendations from faraway bureaucrats or plans designed in an office don't always meet that standard. A push by faraway bureaucrats to vaccinate everyone with an experimental vaccine rushed through trials conducted by the vendors sounds like just the sort of thing to give them pause. 

To be fair, my calculation of absolute risk reduction doesn't take herd immunity into consideration. Vaccinations are one way to get to herd immunity--but so is an event like the Redneck Rave. So I'd like to thank all the rednecks who attended, got exposed to COVID, and hopefully developed some immunity to it during summer, when they're less likely to end up in the hospital.