- Researchers report that side effects appear to be stronger from COVID-19 boosters than from initial doses of the vaccine.
- The lower-severity side effects include fatigue, lymph node swelling, and nausea.
- Experts say the side effects may be stronger because the immune system reacts more strongly to succeeding vaccine doses.
Your protection against COVID-19 begins to
While vaccine boosters help protect everyone against serious illness, some people may experience some symptom-like side effects.
Rare “low-severity” side effects such as fatigue, lymph node swelling, and nausea are more common after receiving the COVID-19 vaccine boosters than with regular doses, according to a
Rare, lower-severity side effects reported in the study include:
- Lymph node swelling
- Joint and muscle pain
In February, the Centers for Disease Control and Prevention (CDC) modified its guidance on intervals between the initial two doses of COVID-19 shots.
It expanded the interval to 8 weeks for the Pfizer and Moderna vaccines for most people 12 years and older. A shorter interval of 3 to 4 weeks is still recommended for people who are moderately or severely immunocompromised as well as adults 65 years and older. People who live in communities with high levels of COVID-19 cases are also urged to consider the shorter time period
Dr. Michael Daignault, the chief medical advisor at Reliant Health Services, told Healthline that the CDC’s new recommendation matches what doctors have been advocating and what Canada and European Union countries already recognize that the interval between doses is the optimal strategy to ensure a robust and long-lasting immune response against COVID-19.
Dr. Erika Schwartz, an author and the founder of Evolved Science, notes that the symptoms after a booster are similar to the symptoms of COVID-19 itself. That’s because our immune system is trying to build immunity against COVID-19.
“Immune system reactions usually are signs that our immune system is fighting an infection, whether from the actual disease or [as a reaction to] a vaccine,” Schwartz told Healthline.
Daignault clarifies that side effects after vaccination do not correlate with a stronger immune response, “just as the absence of side effects don’t indicate a poor immunogenic response.”
The side effects seem to increase as more boosters are used. That may be because the individual immune system reacts more strongly with each new shot, explained Schwartz.
However, the COVID-19 vaccines have been administered for less than two years, so scientists are still learning about them.
“This is a very new type of vaccine and the data is not extensive or long enough to explain what is going on,” she noted.
While mortality from COVID-19 in the United States is about 1 percent, the CDC still recommends boosters and probably will continue to do so for the foreseeable future, Schwartz said.
“The government agencies involved are fearful of mutations in the virus that might be more dangerous, although historically viruses like COVID mutate into less and less dangerous variations with the passage of time,” she added.
Schwartz said despite your vaccinations and other prevention measures remain the best weapons against COVID-19.
This means staying home if you’re sick, eating a healthy diet, and getting enough sleep and exercise as well as discussing your personal risk-benefit ratio with a medical professional, she said.