So if you are vaccinated why are still being told to wear a mask?
All the evidence we have shows the COVID vaccines offer strong protection which means the vaccinated have very little risk of hospitalization or death from COVID-19.
And multiple studies show the shots reduce the risk of passing on the virus.
One that looked at the Pfizer vaccine found that even if you did get infected you were 78 percent less likely to spread the virus to household members compared to someone who was unvaccinated.
There is just one problem with those studies — they were done before the Delta variant.
The CDC now says new data from the last few days appears to show that vaccinated people who contract COVID can spread the Delta variant just as easily as unvaccinated people.
Scientists worry that is because people infected with Delta have more of the virus in their bodies.
Researchers have found people with Delta have a thousand times more copies of the virus in their respiratory tracts than the original strain.
Right now, health experts are in a race to stop COVID-19 from spreading since each time it spreads there is a risk it will mutate, possibly creating something even worse than Delta.
And since breakthrough cases appear to be able to spread the virus, health experts are now asking even the vaccinated to wear masks in certain situations.