How long after the second Pfizer vaccine is it effective?

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As distribution and administered shots continue, here are some key questions and answers surrounding the Pfizer vaccine.


How long until a second dose is proven effective?

A study in the New England Journal of Medicine found that after a second dose of the Pfizer vaccine, efficiency rose to 95% after seven or more days.

Are side effects more intense after a second shot?

Possibly, but that isn’t necessarily a bad thing, according to the Centers for Disease Control and Prevention. That means the body is building protection, and those side effects should go away in days.

What are some common side effects?

In the arm where you get the shot, common side effects can be pain, redness and swelling, according to the CDC. In the rest of the body, it can be fatigue, headache, muscle pain, chills, fever and nausea.

Should you still get a second shot if you had side effects from the first shot?

Yes, because that will help get you the most protection, according to the CDC. Only avoid a second shot if it’s recommended by a vaccine provider or doctor.

When vaccinated twice, should you still take precautions?

The CDC says yes. Still try to wash your hands regularly, wear a mask and socially distance, because the CDC is still trying to fully gather data about how vaccines will affect the spread of COVID-19.


About the Author:

Keith is a member of Graham Media Group's Digital Content Team, which produces content for all the company's news websites.