MANKATO — Mankato doctors recently published a review of potential adverse effects of COVID-19 vaccines, finding the benefits far outweigh the rare risks.
The Mayo Clinic Health System research team analyzed reports associated with vaccines available in the United States and elsewhere in the world in 2020 and 2021. Their findings, published in March, are presented in the Official Journal of the Italian Society of infectious and tropical diseases. .
Vaccines are the only available tool offering people some protection against COVID-19, Dr Syed Anjum Khan said. So the idea behind the article was for researchers to gather the best information about vaccine safety.
“As a hospital practice, we care about our community, and we care very much about the southern Minnesota community,” said Khan, one of six researchers involved in the project. “So we really wanted to provide the best evidence.”
All vaccines, including those developed for COVID-19, have risks associated with them. Misinformation about COVID-19 vaccines during the pandemic, however, has helped fuel hesitancy among some groups by exaggerating the risks.
The research findings could help providers communicate with patients about risk factors, said Dr. Hisham Ahmed Mushtaq, who authored the research paper.
“This will provide the provider with a nice detailed list of adverse effects,” he said. “They can educate their patients.”
Adverse events associated with the two most commonly administered vaccines in Minnesota, Moderna’s and Pfizer’s mRNA vaccines, included mild to moderate symptoms ranging from swelling and redness at the injection site to headache and tiredness. Symptoms usually lasted about one to two days.
Younger recipients between the ages of 16 and 55, especially those receiving their second dose, experienced more adverse effects. Younger people have more robust immune responses, Khan said, and the greater response associated with the second dose led to more adverse effects.
“At this time the body recognizes the virus, so the immune response is more robust the second time around,” she said.
The researchers also focused on six specific types of adverse events associated with various vaccines. One of them, thrombosis, led US regulators to temporarily suspend Johnson & Johnson’s use of the vaccine in April 2021.
The break came after six reports of cerebral vein thrombosis, or CVT, after people received vaccines. After investigating the reports, regulators lifted the pause but issued a warning about them for women under 50.
The Mankato researchers noted that the vaccine still provides an overall benefit, as the risk of contracting CVT from COVID-19 is much higher.
“The development of CVT is 41 times more likely in patients with COVID-19 than in those without COVID-19,” they said in the report.
Understanding the risks versus the benefits is important when analyzing vaccine safety, said Dr Brian Bartlett, one of the researchers. For most patients, the risks from vaccines pale in comparison to the risks from COVID-19.
“No drug or vaccine is without risk,” he said. “What we’ve found is that, in our professional experience with the vast majority of patients, the benefits of vaccines outweigh the risks.”
Other reported adverse health effects either had no substantial evidence linking them to COVID-19 vaccines, such as Guillain-Barré syndrome, or had levels of risk too low to outweigh the benefits of the vaccine, such as reactions skin and glomerular disease.
Another adverse health effect, inflammation of the heart known as myocarditis, has been the subject of more than 10,000 cases reported to the Centers for Disease Control and Prevention’s Vaccine Adverse Event Reporting System, or VAERS. But the reports, the researchers concluded, were “infrequent compared to the hundreds of millions of vaccine doses given without adverse effects.”
A separate CDC study also found that patients with COVID-19 had nearly 16 times the risk of developing myocarditis compared to patients without COVID-19.
The VAERS database can be useful for monitoring adverse effects, although it has drawbacks. The submissions may be biased or contain errors, the researchers concluded, and the entries do not indicate a causal relationship between the effects and the vaccines – some effects could occur by chance after vaccination rather than being the direct result of vaccination.
Overall, the goal of the study was to provide people with clean, clear, and objective information about COVID-19 vaccines, Bartlett said. He described the analysis as one of the most in-depth and evidence-based views of risk factors to date during the pandemic.
The findings align with what Khan, Bartlett and other doctors have observed in patients during the pandemic. Vaccinated people were much less likely to have severe COVID-19 than unvaccinated people.
Bartlett credited Khan and his colleagues with helping Mayo at Mankato Hospital have one of the highest COVID-19 survival rates in the country.
“People in this community who had COVID-19 and were hospitalized were much more likely to survive their illness than other hospitals,” he said.
It was a team effort, Khan said, as was the research project. Dr. Anwar Khedr, Dr. Thoyaja Koritala and Dr. Nitesh K. Jain were the other three researchers involved in the analysis.
Seeing so many unvaccinated patients experience severe COVID-19 symptoms during the pandemic has been difficult, Khan and Bartlett said. Publishing a clearly written analysis that put vaccine risks into context was another way to educate people.
“There have been doubts about the vaccine again and we respect their decision,” Khan said. “But we noted that, of all the people admitted to intensive care, around 99% were those who were not vaccinated.