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What to Expect After Getting a COVID-19 Vaccine

August 13, 2021
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So, you're considering getting the COVID-19 vaccine. You might have questions – will there be side effects? Can I gather with friends and family? Do I still need to wear a mask? What about the Delta variant – how safe am I? 

Here, we summarize the current recommendations from the CDC (Centers for Disease Control and Prevention) in answer to some of the most common questions following vaccination.

Will I have side effects?

You might have some side effects following your vaccination. In the arm you received your shot, you might experience soreness, swelling, and sometimes swollen lymph nodes. You may also experience tiredness, headache, muscle soreness, chills, fever and nausea.

Most of these side effect last no more than a few days. You can ask your doctor about taking over-the-counter medicine, such as ibuprofen or acetaminophen, for any pain or fever you experience after vaccination. However, it is not advisable to take this before being vaccinated. These side effects are usually mild to moderate and go away quickly.

How long does it take to be immune after my vaccination?

In general, you will be considered fully vaccinated 2 weeks after the second dose in a 2-dose series (Pfizer and Moderna) or 2 weeks after a single-dose vaccine (Johnson & Johnson).

Can I still test positive for COVID-19?

Yes. None of the vaccinations are 100% effective at preventing COVID-19. Pfizer is 95% effective and Moderna is 94% effective in preventing symptomatic infection. Recent real world data suggest that either mRNA vaccine is effective in preventing 90% of infection including asymptomatic infection.

While none of the vaccinations can give you COVID-19, there is a very small possibility you might still become infected – with much milder symptoms than had you not been vaccinated.

Can I gather with friends and family?

If you've been fully vaccinated:

  • You can resume activities that you did prior to the pandemic.
  • To reduce the risk of being infected with the Delta variant and possibly spreading it to others, the CDC recommends wearing a mask indoors in public.
  • Be especially cautious if you live in an area with a high level of vaccine transmission or if you or others in your household are at a high risk of getting severely sick.

Read the CDC's full recommendation. 

What if I am exposed to COVID-19 after being fully vaccinated?

If you’ve been around someone who has COVID-19, you do not need to quarantine for 10 days or get tested for COVID-19, unless you have symptoms.

Do I still need to wear a mask in public?

In public settings you should still wear a mask if you are in an area of high transmission or if you're at high risk. No vaccines are 100% effective, but they do reduce your risk of hospitalization and death if you do happen to be infected after immunization. It is also important to keep wearing a mask to protect high risk people from being infected.

How much do you know?

Test you knowledge about COVID-19 vaccines with this quiz from the Centers for Disease Control and Prevention. 

Get Your COVID Shot

CDC recommends everyone ages 5 and older get a COVID-19 vaccine to help protect against COVID-19.

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