COVID-19 vaccines were tested in large clinical trials to make sure they meet safety standards. Many people were recruited to participate in these trials to see how the vaccines offer protection to people of different ages, races, and ethnicities, as well as those with different medical conditions. Though the accelerated timeline for vaccine development was unprecedented, safety remains a top priority.

There are currently three available vaccine types in the US.  All three are considered quite effective.  Additional COVID-19 vaccines remain in clinical trial phases.

• Moderna
• Pfizer
• Johnson & Johnson
• Novavax

Exact levels of efficacy may vary as new COVID-19 variants emerge, and this continues to be studied.  For up to date information from the CDC regarding effectiveness of the above vaccines, visit the CDC website.

Most people do not have serious problems after receiving a vaccine. Some people might experience temporary injection site soreness, fever, chills, fatigue, headache, and  muscle pain after receiving the COVID-19 vaccines. 

All of these side effects should go away in 24 to 48 hours. If you experience any symptoms after vaccination, you may choose to take an over-the-counter fever reducer or pain reliever. 

Most side effects are normal signs that your body is building protection. Historical information and on-going research shows us that long-term side effects are typically not a concern with vaccines. Severe and serious side effects of vaccines are rare and when they do occur, it is usually within 6 weeks of receiving a vaccine. Research related to the COVID-19 vaccines will continue, and the FDA and CDC are continuing to monitor safety to ensure long-term side effects are identified, should they arise. If an issue is identified, experts will take immediate action to determine the best course of action. 

If you previously tested positive for COVID-19, you may still receive the vaccine, provided you have completed your period of isolation and are asymptomatic. 

Reinfection with the COVID-19 virus is possible and experts do not yet know how long someone is protected from getting sick again after recovering from COVID-19. If you are able, receiving the vaccine is the best way to protect yourself. 

The Centers for Disease Control and Prevention (CDC), in collaboration with other public health agencies, continue to monitor emerging SARS-CoV-2 variants closely.  

While there is evidence from laboratory studies that show current vaccines may be less effective against some of the newly identified strains, the immune response is incredibly complex, so the vaccine is still expected to provide some degree of protection.  

These variants, including Omicron and its sub-variants, seem to spread more easily and quickly than other variants, which may lead to more cases of COVID-19. An increase in the number of cases will put more strain on healthcare resources, lead to more hospitalizations, and potentially more deaths.

At this time much remains unknown.  However, it is normal and expected for mutations to occur in many types of viruses.  For instance, we deal with mutations in the flu every year. Experts will continue to monitor SARS-CoV-2 variants and if necessary, the vaccine development process can accommodate changes, though we are not at that point right now. 

As a reminder, even after receiving the vaccine, everyone should continue engage in good hand hygiene, and stay home when not feeling well.

For additional information, please visit the 4Maryland website.

We encourage you to talk with your primary care physician, or schedule an appointment to talk with a University Health Center provider, as you have questions about your personal health and wellbeing. You may also decide to closely review the information here and from other reputable health care organizations. 

Boosters are an important part of protecting yourself from getting seriously ill or dying from COVID-19. They are recommended for most people. 

Click here for more information about COVID-19 boosters, including the updated bivalent booster.