What's inside the COVID-19 vaccine and how does it work?

About one million Texans have received the COVID-19 vaccine so far, but many people still remain hesitant to get one.

To answer some of the questions surrounding the vaccine, ABC13 hosted a COVID-19 Vaccine Rollout town hall on Tuesday.

One of the biggest questions people asked were what's in the vaccine and how does it work.

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The Pfizer vaccine contains mRNA lipids, which stands for messenger RNA, like potassium chloride and sodium chloride.

When the Pfizer vaccine was authorized, some people posted on social media claiming adding potassium chloride to the vaccine was like adding poison since it's an ingredient used in lethal injection drugs. But according to health experts, potassium chloride is found in almost all foods we eat, and the amount added to the Pfizer vaccine is equivalent to a pinch of salt.

The Moderna vaccine also contains mRNA lipids, but different kinds like sodium acetate.

Both vaccines also have preservatives to keep the vaccine intact.

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The mRNA contains instructions for immune cells in our body to make a harmless piece of the COVID-19 spike protein.

After injection, the immune cells get to work making the protein. After it's made, the cells break down the instructions and get rid of them.

READ MORE: Houston doctor explains what you need to know after getting the COVID-19 vaccine

The new protein piece is then displayed on the surface of the immune cells. The immune system is alerted to the presence of something that shouldn't be there, triggering a response similar to if we had a natural infection. That's why minor symptoms like fever or chills can occur after taking the vaccine, but they usually subside a few days after.

The immune response then creates antibodies which will protect us from becoming infected by the real virus.

The FDA is continuing to monitor the vaccines, and the CDC has said no major side effects have been reported.
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