The Surprising New Cleveland Clinic Study on the Bivalent Vaccine Efficacy

The Cleveland Clinic studied over 51,000 employees to see how effective the bivalent Covid-19 vaccines have been up until the close of the study on December 12, 2022. The start date was September 12, 2022. They specifically looked at reinfection incidence with covid-19 after one, two, three, and three-plus vaccines. The results are neatly presented in a line graph which we will look at later in this post. Two things really stand out. The first is that the more vaccinations the employees received, the more Covid-19 they got. The second thing is how the research paper described the vaccines as effective. I can't tell if this is a joke, as the paper is in pre-print and under peer review. First, we will look at the study with the results, and then we will review their uncanny conclusions and discussion. You can read the study here.

 This study aimed to evaluate whether the new bivalent COVID-19 vaccine protects against COVID-19. The strengths of their study include the large sample size and its accounting for who had COVID-19, when COVID-19 was diagnosed, who received a COVID-19 vaccine, and when. The study methodology, treating bivalent vaccination as a time-dependent covariate, allowed for determining vaccine effectiveness in real-time. A potential weakness is that the average age of the employees was only 42, the age for which most covid infections are rarely severe or fatal. For this reason, the researchers claimed not to be able to determine if the vaccines led to milder cases with fewer symptoms. 

The major flaw in the study, as in all vaccine studies, is that the individuals were considered unvaccinated until one week after their injections. Curves for the bivalent vaccinated state were based on data from when the bivalent vaccination status changed to "vaccinated." This meant that the vaccinated group could have had covid cases in the first week that got placed in the unvaccinated category.

 The Data

https://www.medrxiv.org/content/10.1101/2022.12.17.22283625v1

As we can see from the line graph, the unvaccinated group (black) had the lowest infection rate. Those with one dose (red) had more post-vaccination infections than those with none, and those with two doses (green) had more cases than those with one. Those with three vaccinations (blue) had even more than those with two. Finally, the people in the three-plus vaccination group (orange) had the most covid infections. 

The results are clear: unvaccinated employees at the Cleveland Clinic had the least amount of covid infections. The odds of getting covid went up with each successive injection. 

The researchers' conclusion is baffling because they claim that the new bivalent vaccine given to working-aged people offered modest protection against covid. I don't know how they can claim protection because their data shows that the more vaccinations workers had, the greater the odds of catching covid. 

The researchers summarize that the bivalent COVID-19 vaccine booster was 30% effective in preventing infection. A likely explanation is that the data represented in the pre-print version may be erroneously represented. Another explanation is that the researchers intentionally concluded incorrectly to help their study get published. 

You may be surprised to find that researchers do this all the time in papers- the data says one thing, and the conclusion is backward. The famous Minnesota Coronary study had data that showed lowering cholesterol using vegetable oil resulted in more death. It took about a decade for the study to be published, and the conclusion was that it was best to lower cholesterol with vegetable oil! You can read more about that study in my post here.

In the discussion portion, the authors skirted around the issue of natural immunity from previous covid infections. They stated that the more recent the previous COVID-19 episode was, the lower the risk of COVID-19, and the greater the number of vaccine doses previously received, the higher the risk of COVID-19. Their statement insinuates that previous covid infection confers immunity that wanes with time. They unusually claim that higher immunity from previous asymptomatic infections may account for the vaccines appearing worse, but this is the opposite of reality-if one is already immune, the boosters would appear to be the cause of the immunity. They also laud the original vaccines as being 97% effective, which any data have never born out. So, they were merely regurgitating the manufacturer's hyperbole and not relying on any proven facts. 

What they got right

The authors state, "The association of increased risk of COVID-19 with higher numbers of prior vaccine doses in our study was unexpected...those who chose not to follow the CDC's recommendations on remaining updated with COVID-19 vaccination, and one could reasonably expect these individuals to have been more likely to have exhibited higher risk-taking behavior Despite this, their risk of acquiring COVID-19 was lower than those who received a larger number of prior vaccine doses. " Finally, the researchers describe a few more studies demonstrating covid vaccines cause a higher risk of covid infection.

Although they concluded that the vaccines offered moderate immunity, they suggest that more studies on multiple doses should be done, given that it appears, based on their data, that more boosters result in higher risk. We will see whether this data gets published. It won't get published in its current state. They need to remove wording that makes the vaccines look ineffective or parse the data differently. Perhaps by making the interval after each boost two weeks, more cases will end up being counted in the none or lower boosted categories. This is, unfortunately, how most of the studies have been done to date. So, even if boosters are placebos, counting cases for the first two weeks after they are given and placing them in the unboosted category makes them seem effective. In the end, you must read a study AND question the researchers to avoid ending up with false beliefs. Again, this paper shows that more boosters gave the workers a higher risk, but the authors state that the bivalent vaccines are moderately effective. Which is it?