Doctor explains why the COVID-19 vaccine's 2nd dose has side effects

As many people start receiving their second shot of the coronavirus vaccine, FOX 35 is looking into why some people have side effects from the second dose.

"Anytime something foreign enters the body, the body sees it as that -- something foreign," Dr. Jason Littleton said. "It tries to recognize it. If it can’t recognize it. It tries to attack it."

The Centers for Disease Control and Prevention (CDC) said last month that extreme allergic reactions to the vaccine are rare. However, some people experience mild to moderate side effects because their body is trying to develop an immunity to coronavirus.

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"The body sees that and says, ‘Hey, this doesn’t belong to us. We need to attack this by generating antibodies,’" Dr. Littleton said. "Through that type of reaction, the body, what we call an immune response, is basically defending itself against it."

Dr. Littleton said that if you experience severe side effects, like an allergic reaction or throat closing, you need to call 911 immediately.

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