Some COVID Infections After Vaccine Are Expected
The Claim
The news that 246 fully vaccinated Michigan residents tested positive for COVID-19 is cause to question the vaccine's efficacy.
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Emerging story
This week, social media users were alarmed by headlines such as the following from the Detroit News: “246 vaccinated residents diagnosed with COVID; 3 dead, Michigan reports.” The article explains the context behind the headline, but people began sharing the article with comments such as “But we thought the vaccines were 100% effective at preventing serious illness?” and adding quotations around “fully vaccinated” to denote skepticism. Users took the news as evidence that the vaccines may be ineffective.
Misbar’s Analysis
In addressing the claims that 246 fully vaccinated people contracted COVID-19 and 3 of them died, one needs to put effectiveness rates to the test. The article causing the alarm notes that as of April 4th, 2.95 million residents had been vaccinated with either one or two doses. One percent (1%) of 2.95 million people is 29,500 people and .01% is 295 people. So, at 246, the number of people in Michigan that have contracted COVID after immunization is less than one tenth of a percent (.01%). Only three of those 246 died. All three of those people were 65 years old or older, which is widely regarded as one of the major contributing factors of severe illness. They also may have been infected prior to being vaccinated. These circumstances fall in line with the expectations of medical experts, and they do not reasonably put the efficacy of the vaccine into question.
Medical professionals state that no vaccine is 100% effective. For example, both Pfizer and Moderna’s vaccines have proven to be 95% effective. One study was released after early clinical trials touting the AstraZeneca vaccine as 100% effective against severe COVID-19 infections, with a 72% effectiveness rate against milder cases. Further trials were conducted and, as expected with a larger sample size, effectiveness rates were lowered from 100%. Some confusion is understandable without a knowledge of how clinical trials work.
Clinical trials occur in several phases. The first phase is the smallest group of people and each subsequent phase has a larger group and also represents a more varied selection of the population. The phase with 100% efficacy for this vaccine was only the first phase of the trial.
