New research from Israel offers some surprising but reassuring news about the safety of covid-19 vaccines. The study found that the Pfizer / BioNTech mRNA vaccine was not associated with a higher risk of most potential side effects. And for rare suspected complications such as myocarditis, the risk was still significantly higher in those who received covid-19.
When symptoms appear after taking a drug or vaccine, they are known as side effects. These events may be true side effects of a treatment, but they may have occurred regardless of the drug. An important way to determine the risk of a potential side effect is to see how often a population of people who received the treatment experience these symptoms compared to those who did not take the treatment, as the latter was a control group in the real world. And that’s what these researchers did by looking at data from the largest health care system in Israel from the start of the vaccination campaign late last year. The study involved a total of more than one million people.
The researchers compared the number of side effects documented in vaccinated people with unvaccinated people that matched age and other demographics. In the end, they found that the vaccine was not associated with a higher risk of most side effects in the 42 days after vaccination. However, there were some incidents with a stronger link to vaccination. These included appendicitis, swollen lymph nodes, and myocarditis (inflammation of the heart). But when the researchers then looked at people with confirmed covid-19 and compared them to vaccinated people, the difference was huge.
Potentially serious side effects were much more common in the infected than in the vaccinated. For example, myocarditis in the vaccinated 2.7 cases was documented for every 100,000 people, but it was 11 cases per. 100,000 in the infected – a quadrupling. There were also other conditions that vaccinated people had no additional risk of experiencing, but were more likely to appear in people who got covid-19, such as heart attacks, kidney damage, and pulmonary embolism.
“[O]Your results indicate that SARS-CoV-2 infection is in itself a very strong risk factor for myocarditis, and it also significantly increases the risk of several other serious side effects, ”the authors wrote in their study, published Wednesday in the New England Journal of Medicine.
Although it may seem obvious that it will be safer to take a vaccine to get immunity to a disease than to catch the disease yourself – especially a disease that has been killed 4.5 million people in less than two years – it is always important to keep an eye out for any major side effects that may have gone unnoticed in clinical trials.
Since their approval last year, researchers have found that vaccinated people may be at higher risk for some side effects that were not documented in the original clinical trials, including myocarditis in those receiving an mRNA vaccine such as Pfizer or Moderna shots. . And there have been cases of serious illness and even deaths linked to vaccines, such as death by BBC journalist Lisa Shaw in May following a rare blood clot condition linked to the AstraZeneca vaccine. But so far, all real-world data has shown that such serious incidents are still very rare, while covid-19 deaths and long-term complications are far more common. In the United States alone, vaccines can have prevented up to 140,000 deaths in early May. In other words, the benefits of covid-19 vaccination continue to outweigh any risks.