Choose the health content that’s right for you, and get it delivered right in your inbox.

Article Type: Blog

What to Know About Coronavirus Vaccines and Their Side Effects


2 items. To interact with these items, press Control-Option-Shift-Right Arrow
  • AdventHealth
  • Health and Wellness

What to Know About Coronavirus Vaccines and Their Side Effects

With the first coronavirus vaccines being approved and distributed to health care workers first (per the CDC guidelines) we’re turning a corner on this year and looking forward to better days ahead. 

Coronavirus vaccines from pharmaceutical companies Moderna and Pfizer have shown strong promise in protecting against COVID-19 in clinical trials, with Moderna being 94.5% effective and Pfizer 95% effective. Front-line health care workers have already started receiving the Pfizer vaccine across the country, and Moderna is in line to be distributed next. 

What’s the Difference Between the Moderna and Pfizer Vaccines?

While both vaccines are over 94% effective, their clinical trials have been slightly different. Pfizer’s vaccine prevented coronavirus in all but eight of the 18,198 study participants who were tracked for about two months after receiving the second dose of the vaccine. 

The Moderna vaccine, on the other hand, had five of the 13,934 study participants develop coronavirus after being tracked for about seven weeks after their second dose. 

Vaccines from both companies have been effective in older adults, but Moderna was 100% effective in participants aged 65 and older, while Pfizer was 93.7% effective in those ages 56 and older. 

The Most Important Takeaway

AdventHealth experts agree that both the Pfizer and Moderna COVID-19 vaccines are safe and effective, and we have already started giving vaccinations to health care personnel. 

There have been reports of certain side effects being linked to the vaccine, but neither company’s vaccines have caused issues that would hold up an emergency use authorization from the FDA. 

Coronavirus Vaccine Side Effects 

So far, the most common side effect reported from those who have received the vaccine is an injection-site reaction. The Pfizer vaccine is administered in two doses, three weeks apart, and many of the side effects reported were after people got the second dose. 

In a document submitted by Pfizer to the FDA, it was reported that coronavirus vaccine side effects included:

  • An injection-site reaction (84% of people had this)
  • Fatigue (63% of people had this) 
  • Headache (55% of people had this)
  • Muscle pain (38% of people had this)
  • Fever (14% of people had this)
  • Chills (lesser-reported side effect)
  • Upset stomach (lesser-reported side effect)

Overall, the symptoms may cause discomfort for some, but that’s actually a result of the immune response brought on by a vaccine. Many vaccines, including the flu shot, give some people mild symptoms. 

The Bottom Line: Mild Side Effects Are Normal and Will Pass

Moderate vaccine side effects, such as headache and fatigue, are not a cause for alarm. Whether you do get side effects after the first dose or not (both scenarios are considered normal), the second dose is still needed to provide protection against COVID-19. 

From what we know so far, these coronavirus vaccine side effects are temporary, and shouldn’t discourage anyone from getting this potentially life-saving immunization.

Your Source for Trusted Coronavirus Vaccine Updates

With something as important as the coronavirus vaccine, you need to hear from a medical team who has your whole health in mind. For more coronavirus vaccine information from our medical experts, visit our Coronavirus Vaccine Resource Hub.


2 items. To interact with these items, press Control-Option-Shift-Right Arrow
  • AdventHealth
  • Health and Wellness