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10 Things You Should Know About the COVID Vaccine

Monday, December 14, 2020 2:43 PM

From the factory to the frontlines, “The Vaccine” everyone’s been waiting for is here.

Making headlines lately is news of the recently approved Pfizer-BioNTech COVID-19 Vaccine by the U.S. Food and Drug Administration (FDA) for (SARS-CoV-2). However, there’s still a lot of curiosity and questions about safety, efficacy, its distribution and more.

COVID Vaccine

Here are 10 things you should know about the vaccine provided by our experts at NorthShore University HealthSystem: 

1. Is the vaccine safe? What is the scientific data behind it? 

The Pfizer and Moderna vaccines are being distributed under Emergency Use Authorization (EUA) from the Food and Drug Administration (FDA). An FDA committee granted an EUA for the Pfizer vaccine on Dec. 10, and the Moderna vaccine will be reviewed a week later. Our recommendations assume that both EUAs will be granted. In order for an EUA to be granted, the data submitted is rigorously reviewed by teams of FDA scientists. But this data is yet to be published in the peer-reviewed literature.

2. Can I get COVID-19 from the vaccine?
No. While the vaccine doesn’t contain either live or dead virus, you may develop “flu-like” symptoms such as tiredness, fevers or headaches after receiving one or both doses of the vaccine but these usually resolve within three days.

3. How do the Pfizer and Modern vaccines work?
Both are forms of a new type of vaccine that involves injecting mRNA, which replicates the spike protein on the COVID-19 virus. Once you’re injected with the vaccine, your body begins to manufacture the same spike protein to create antibodies to fight it. If you’ve taken the vaccine and are later exposed to COVID-19, the antibodies created inside your body will keep the virus from entering the cells and causing an infection.

4. What do we know about the vaccines' efficacy? 
The data submitted show that the Pfizer and Moderna vaccines have an efficacy of at least 90 percent after 2 doses. Vaccine efficacy of 90 percent means that the vaccine will protect 9 out of 10 individuals from contracting the infection. The data also show that vaccinated individuals have more mild symptoms if infected and didn’t need to be hospitalized as often.

5. How long does it take for the vaccine to become effective? 
It typically takes at least a week after the second vaccine dose or approximately one month after you start the two-vaccine series. That means it's possible you could be infected with the virus that causes COVID-19 just before or just after vaccination and get sick. This is because the vaccine has not had enough time to provide protection. So it’s very important that you continue the key safety practices of facemasks, hand hygiene, and social distancing.

6. Are there vaccine side effects for various populations - including the elderly and younger children? 
We currently only have safety data from the short-term duration of the study trial. This means that we don’t know all of the potential side effects of the vaccine, particularly long-term side effects. We do know that the following have been reported as possible side effects that can last up to a week after receiving the vaccine:

  • Pain and redness at the injection site
  • Feeling tired and run down a day after receiving the vaccine
  • Headache, muscle aches, chills, joint pains, or fever
  • Possible allergic reaction in individuals with known allergies

At this time, vaccine trials including children, or pregnant or breastfeeding women have not been completed. Vaccines can affect children differently than adults, so further testing will be necessary to make sure any coronavirus vaccine is safe for children.

A handful of recently vaccinated people in the United Kingdom have reported an allergic reaction after receiving the initial injection. This isn’t unusual. However, if you’re prone to severe allergic reactions from vaccines or injections, you should first consult with your physician before getting vaccinated.

7. How long will the vaccine protect me against COVID-19? 
While the vaccine prevented individuals in the clinical trials from getting COVID in the 90 days after completing the vaccine series, we don’t know how long this protection will last beyond that time frame. Both Pfizer and Moderna began their clinical trials in late July, so they’ve been able to follow their volunteers for only six months. It’s conceivable that the vaccines can provide long-lasting protection, or effectiveness could fade away in under a year and require a booster shot annually. We need more data and time to understand how long the vaccine will last.

8. What if I'm immune-compromised or have an autoimmune disorder? Would it be optimal for me to get vaccinated now or wait?
For people who have immunodeficiencies, the COVID-19 vaccine likely will be as effective as it is for the general population. Experts in the field believe that since both vaccines use mRNA—and not live virus—the injection would potentially be suitable for immune-deficient patients. It’s still unclear how the vaccine will work for those who have antibody deficiencies, as they could likely have an incomplete response. Immune-compromised employees should discuss with their physician before deciding on whether to get vaccinated.

9. If someone has previously had COVID, should they get the vaccine? 
Due to the severe health risks associated with COVID-19 and the fact that re-infection is possible, people may be advised to get a vaccine even if they have been sick with the virus before. If you have had a previous COVID infection, you should wait at least 10 days since your symptom-onset or test date with resolving symptoms before receiving the vaccine.

10. Who shouldn't receive the COVID-19 vaccine? 
The Pfizer or Moderna vaccines should NOT be given if you’re known to have anaphylactic reactions to polyethylene glycol—the active ingredient in Miralax or colonoscopy prep. If you’re allergic to any component of the Pfizer or Moderna COVID-19 vaccine, you should NOT receive it. Click here to review a list of vaccine ingredients and get links to additional resources. If you’ve ever had a negative reaction to any vaccine or injectable therapy, extra caution should be taken—including a 30-minute monitoring after vaccination. If you had an anaphylaxis reaction to the first dose of the vaccine, you should not get the second dose, or speak to an allergist before proceeding.