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Do COVID vaccines put people at more risk of COVID?

The Claim:

Anti-vaxxers are claiming that a Cleveland Clinic study proves that COVID vaccination puts people at greater risk for catching COVID.

The Facts:

The study looked at whether people who are “up-to-date” on their COVID-19 vaccines (meaning they got at least one dose of the new COVID-19 bivalent vaccine) are less likely to get COVID-19 compared to those who are not “up-to-date.” They studied employees of the Cleveland Clinic during the time when a new version of the COVID-19 virus (XBB lineages) was common.

However, it looks like many people haven’t read the whole study. What it really found was that the bivalent COVID-19 vaccine actually lowers the risk of infection.

The misunderstanding comes from misreading the figures contained in the study. This is called a Table 2 fallacy. Often, epidemiologists need to pool together data to come up with an estimate of risk, known as an adjusted effect estimate. A Table 2 fallacy results from multiple adjusted effect estimates from a single model presented in a single table. Problems arise when different types of estimates are presented on the same table. This fallacy is like saying that carrying a lighter makes you more likely to get lung cancer, without considering whether the person smokes. In studies, it’s important to adjust for the right things.

For the Cleveland Clinic study, when the last dose was given to someone is more important than just counting how many doses they had. You can’t conclude from the data that more vaccine doses leave one more susceptible to COVID, but you can conclude that the booster was associated with reduced COVID risk.

The actual results of the study conclude that “the bivalent COVID-19 vaccine booster was 30% effective in preventing infection, during the time when the virus strains dominant in the community were represented in the vaccine.” Additionally, another study in the New England Journal of Medicine also showed that the bivalent booster did work: 59% effective against hospitalization and 62% against hospitalization or death.

Do polio and measles vaccines work?

The Claim:

An anti-vaccine activist is once again claiming that vaccines for polio and measles do not provide immunity. He supports this claim by saying measles deaths dropped before the vaccine came out and polio rates dropped because the CDC redefined polio.

The Facts:

Measles is one of the most transmissible infections in humans. One infected person can infect 12-18 others in a group of susceptible people. Prior to vaccines, it was expected that nearly everybody would get measles at some point in their life, usually during childhood. If the measles vaccine conferred no immunity, as the tweeter suggests, measles would still be circulating freely. Instead, almost no one gets measles anymore.

Yes, measles mortality did decline before the introduction of the measles vaccine due to better medical treatments. Measles cases, however, did not decline until after vaccination began.

This common trope relies on confusing death (mortality) and illness (morbidity). Medical advances slowed down the death rate from measles, but vaccines stopped it.

As for polio, it has not been redefined. The elimination of polio, especially in the United States, was primarily due to the widespread use of effective vaccines. The development of the polio vaccine in the 1950s was a significant breakthrough in medical science. These vaccines were highly effective in preventing polio, and gave mid-century children their childhoods back and parents peace of mind.

The definition of polio, an illness caused by a specific virus called poliovirus, which can be isolated and tested for, that affects the nervous system, has remained consistent over the years. Furthermore, polio is identifiable by more than just the words used to describe it. The virus has been visible through an electron microscope since the 1950s. Polio surveillance of wastewater worldwide alerts global health experts where the disease may be spreading. None of these tests for polio rely on a definition, and that’s why we can be sure that polio didn’t go away because the CDC changed the words to describe it.

Global Health scientists have been involved in a global polio eradication initiative, which has been successful in drastically reducing polio cases worldwide through mass immunization campaigns and surveillance.

Do vaccines cause more cardiac problems than reported?

The Claim:

paramedic claims that he transported many patients to the ER with strokes or heart attacks, and doctors scoffed at his suggestion that these were caused by the vaccine. He says this is proof that cardiac events are underreported to VAERS.

The Facts:

This paramedic had no evidence that the patients with strokes and heart attacks he transported to the hospital were caused by mRNA vaccines. He has probably sought out information that would confirm his own biases against the vaccines. Instead, we need to look at what the evidence tell us.

COVID itself can to contribute to strokes and heart attacks. However, studies show the opposite for vaccines, including this latest study that shows that staying current with COVID-19 vaccines cuts the risk of strokes, blood clots, and heart attacks in half in people over 65 and those with certain health conditions. The study involved over 12.7 million older adults and about 78,600 people with severe kidney disease. It found that the bivalent booster is about 47% effective in preventing heart-related issues in the older group, and 51% effective in the kidney disease group.

Some people may get myocarditis risk and blood clot risk confused and jump to these conclusions. The mRNA vaccines do carry a small risk of myocarditis in young men and adolescent boys, but it often resolves on its own relatively quickly. Anti-vaccine activists have used prior concerns about a particular type of blood clot associated with adenovirus vector vaccines. mRNA vaccines have a minimal risk of blood clots. These facts contradict rather than confirm the paramedic’s bias.

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