First, a COVID-19 mRNA vaccine is injected into a muscle in your upper arm. Some muscle cells take the mRNA instructions in the vaccine and make a harmless piece of a protein called a spike protein.

Many people first learned about mRNA vaccines during the coronavirus pandemic, when the companies Pfizer-BioNTech and Moderna released their COVID-19 vaccines. The Pfizer-BioNTech shot was the ...

But mRNA vaccines work particularly well in this situation because they can be made so fast. If you want to make a bunch of doses of a vaccine, you need to actually grow those viruses somehow.

The new genetic vaccines to prevent Covid-19 infections use mRNA technology, instead of the approach used in traditional vaccines, like those for measles and polio. These new genetic vaccines ...

By comparison, "mRNA vaccines can be developed and manufactured at a faster rate than other kinds of vaccines, which may be important when a new virus emerges or evolves quickly like we have seen ...

AP Photo/Paul Sancya 5. Subzero storage makes distribution a challenge For all of their amazing attributes, mRNA vaccines do have at least one weakness: “If they get too warm or too cold they spoil.

So how do mRNA vaccines work? Katalin Karikó, the Penn Medicine-scientist whose research laid the foundation for both the Pfizer and Moderna COVID vaccines, calls it a “middleman between ...

Cells break down mRNA quickly once it's used, so these molecules will not linger in the body. They also do not enter the nucleus so they will not impact a person's DNA. Scientist Katalin Karikó has ...

How do we know mRNA vaccines work? Moderna and Pfizer’s Covid-19 vaccines were cleared for use based on large studies that enrolled tens of thousands of volunteers.

Vaccines also work on a community level. Some people can't be vaccinated, either because they are too young, or because their immune systems are too weak, according to the CDC.