Science, safety and efficacy

Why Get the COVID-19 Vaccine

The authorized COVID-19 vaccines are important tools in our fight against COVID-19. 

Based on both clinical trial and real-world data, the COVID-19 vaccines are: 

  • Safe with limited short-term side effects. Millions of Americans have now safely received a COVID-19 vaccine. 
  • Highly effective in prevention of: COVID-19 infections, hospitalizations related to COVID-19 and deaths related to COVID-19. 
  • Effective in reducing the severity of infection for those rare, vaccinated individuals who may still get COVID-19. 

There’s been a lot of news in the fight against COVID-19 and the quest for reliable information can be difficult. In this video, Dr. Liam Sullivan tackles some of the questions we’ve received from Spectrum Health team members and our patients alike. Below the video is a breakdown of the questions asked and the time they appear to help guide you as you watch.

Questions & Answers About COVID-19

Questions From Video With Timestamps

1:37: A leading question we get is about "breakthrough infections" - Those who have the vaccine but still get COVID-19. How often do we see that? 

3:25: Do we test for the Delta variant? What do we know about the efficacy of the vaccine against the Delta variant? 

5:12: For those who have had COVID-19, is the vaccine still necessary for them? 

6:36: Lets talk about masking. There is a lot of frustration there... Why have we reverted in many cases to the suggestion, and in some cases requirement, of having even vaccinated people wear masks?

8:36: There is a lot of discussion now about a booster dose for those already vaccinated. How does this help? 

9:38: How can you be so sure that the vaccine is SAFE when it's only been around for less than a year? 

13:35: How significant is this FDA approval that was announced this week? 

14:26: There is no doubt of fatigue when it comes to this - for our team here at Spectrum Health - and the community at large. What keeps you going and do you think we'll ever get out of this?

Straight Talk About the COVID-19 Vaccine

A consolidated and helpful handout addressing frequently asked questions about the COVID-19 vaccine.

Get To Know the Vaccines

Additional Information for Johnson & Johnson (Janssen)

Keeping you informed is important to us. Here are a few things to know about the Johnson & Johnson (Janssen) COVID-19 vaccine and additional resources: 

  • The Johnson & Johnson (Janssen) COVID-19 vaccine is administered in a single dose. 
  • The FDA and CDC have recommended that the use of the Johnson & Johnson (Janssen) COVID-19 vaccine resume in the United States, effective April 23, 2021. Here is the CDC/FDA statement
  • A review of all available data currently shows that the Johnson & Johnson (Janssen) COVID-19 Vaccine’s known and potential benefits outweigh its known and potential risks. The FDA released this Emergency Use Authorization fact sheet with more information about the vaccine and its allowed use. 
  • Women younger than 50 years old should be aware of the rare but increased risk of blood clots with low platelets after vaccination.

How Vaccines Work & the FDA Process

How Vaccines Work

Vaccines work by tricking the immune system to fight off an infection. They do this in different ways. Some use weakened versions of the virus that are unable to cause illness (chicken pox and measles); some use dead virus (influenza); and the COVID-19 vaccine uses pieces of the virus to target a specific protein on the surface of the virus. 

Messenger RNA (mRNA) is a genetic coding material that is translated by cells into a protein. mRNA historically has been very unstable and easily broken down by the human body, which makes it challenging to study. Recent technological advancements have reduced these challenges and improved the stability, safety and effectiveness of mRNA vaccines. Both the Pfizer and Moderna vaccines use mRNA that encodes the spike protein from SARS CoV-2, which is the main protein the immune system uses to respond to the virus. 

Unlike an mRNA vaccine, the Johnson and Johnson vaccine is an Adenovirus vector vaccine, which has been extensively studied and used safely in clinical studies involving vaccines for Ebola virus, RSV, HIV, Malaria, HPV and Zika virus. 

Watch and listen as Spectrum Health experts briefly answer these commonly asked questions about how vaccines work:

Vaccine Efficacy

mRNA Vaccines

Herd Immunity

Clinical Trials, Safety & Efficacy

The FDA has rigorous scientific and regulatory processes in place to help ensure the safety and effectiveness of a vaccine. For the COVID-19 vaccines, which have been authorized for emergency use during the pandemic, the FDA granted authorization after finding sufficient evidence that in clinical trials the vaccines were effective and safe. The vaccine manufacturers are continuing to collect “real-world” data about their long-term safety and efficacy. Eventually, these data may help support full FDA approval of the vaccines. Spectrum Health strongly encourages everyone eligible to get a COVID-19 vaccine. Our clinical experts have extensively reviewed each of the vaccines’ clinical trial data as well as data collected since the vaccines became available for public use. 

Johnson & Johnson Vaccine FAQs

Vaccine Safety

Pregnant & Lactating Individuals

The American College of Obstetricians and Gynecologists (ACOG) recommends that COVID-19 vaccines should not be withheld from pregnant individuals who meet criteria for vaccination. Learn more about their recommendations for pregnant and lactating patients, and have a discussion with your health care provider about your specific situation.


At this time, the Pfizer vaccine has received emergency use authorization for individuals 12 and older. The Moderna and Johnson and Johnson vaccines are not authorized for anyone younger than 18.


The Advisory Committee on Immunization Practices (ACIP) recommends persons with immunocompromising conditions or on immunosuppressive medications receive COVID-19 vaccination unless otherwise contraindicated.

Side Effects

There are usually mild to moderate side effects from the COVID-19 vaccine. The most common side effect caused by the vaccine includes pain at the site where the vaccine was given, which is in the arm. Other side effects may include a headache, fever, chills or muscle aches. The symptoms below are commonly experienced after a vaccine:

  • Injection site pain, swelling or redness 
  • Excessive tiredness or feeling weak 
  • Muscle pain, joint pain 
  • Fever
  • Chills 
  • Headache 
  • Nausea or upset stomach or diarrhea 
  • Swollen lymph nodes

If side effects are worrisome or do not seem to be going away after a few days, a person should contact their primary care provider to further discuss. If the person does not have a primary care provider, we suggest scheduling a virtual visit through the preferred health system’s electronic resources.

If your symptoms are life threatening, call 911 or go to the nearest emergency department.

Allergic or Severe COVID-19 Vaccine Reactions

The Centers for Disease Control and Prevention has a helpful resource here about COVID-19 vaccines for people with allergies or who are concerned about allergic reactions.

Safety Precautions After the COVID-19 Vaccine

At this time, we do not know the impact vaccination will have on transmission of the virus. This will only be answered with studies after widespread vaccine rollout. Safety measures, including mandatory masking, social distancing and pre-procedure COVID-19 testing will still be required until more information is available.

Vaccine Hub Resources