Two different coronavirus vaccines continue to roll out across the United States. But, as millions of Americans get their vaccinations over the coming months, it's important to note that anyone who receives a vaccination could still end up getting sick.
"I would strongly encourage that we move forward with giving states the opportunity to be more expansive in who they can give the vaccine to particularly as more supplies become available," said Stephen Hahn, FDA commissioner.
Health officials continue to say being vaccinated is one of the best ways to protect yourself and others from getting sick. But no vaccine works 100 percent of the time.
During trials, the currently authorized vaccines were shown to be about 95 percent effective, which means some who are vaccinated became symptomatic.
It takes time to build immunity and both authorized vaccines require two doses, given several weeks apart to train the body's immune system. People can be exposed to the coronavirus right before being vaccinated or right after, which does not give the body enough time to develop its defenses.
The CDC says building immunity "typically takes a few weeks." Moderna measured its 95 percent vaccine efficacy starting 14 days after the second dose. Pfizer started seven days after the second dose.
To be clear, the current coronavirus vaccines cannot infect anyone with the virus. They do not contain the virus, but the CDC says vaccinated people should still use all the tools available to us, wear a mask and wash your hands.
The technology used to make the new coronavirus vaccines is designed to be easily adapted if the virus mutates. It should take far less time to update the Moderna and Pfizer vaccines than it takes to make new flu vaccines.