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Why COVID-19 dosage is the same for different size people

COVID-19 vaccine
Posted at 9:45 PM, Feb 18, 2021

Two months into the mass vaccination effort in Arizona and many people still have questions about the COVID-19 vaccines.

FULL COVERAGE: COVID-19 vaccine in Arizona

Among the questions ABC15 has received is this: Why is the dosage the same for different size people?

"It's actually a really good question because there are some medications that are weight based," says Arizona Medical Association President Dr. Ross Goldberg. This vaccine is different because it's MRNA based he says.

"You're actually creating your own antibodies, so you need to kind of light the fire, if you will, to get the furnace going and then your body takes over," Dr. Goldberg adds.

Other vaccines like the annual flu shot and the vaccine for Hepatitis B are also not based on a patient's weight.

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