CDC Director Rochelle Walensky

The federal health agency released new guidance for when Americans need to mask up indoors, saying about 70% of the population lives in a place where it's safe to go mask free.

The CDC held only two telebriefings in 2021. That lack of transparency has prompted criticism — and a pledge from director Dr. Rochelle Walensky to be more open.

Experts weigh in as the federal government urges everyone to get boosted amid concerns over omicron, a new covid variant.

Millions of doses have already been shipped to states, doctors' offices and pharmacies. And pediatricians are getting ready to put shots into little arms. The shots contain a third of the dose given to teens and adults.

With the back and forth on boosters from government agencies, many Americans are wondering if they really need an extra shot. Here is what the science says about who needs a booster now — and why.

If all goes to plan, Americans who got Pfizer or Moderna shots can get a third dose eight months after their last jab. Here's why health officials think you'll need one.

Reversing a months-long downward trend, deaths from COVID-19 have begun rising steadily this week. More than 99% of the recent fatalities were among people who had not been vaccinated.

Dr. Rochelle Walensky says there are areas of low vaccination in the country where cases are rising, and in that situation, the CDC is suggesting that policies be made at the local level.

Biden says, "Today is a great day for America and our long battle with coronavirus. ... It's been made possible by the extraordinary success we've had in vaccinating so many Americans so quickly."

A new Harvard poll shows that only half of Americans trust the CDC — other health agencies were rated even lower. During a pandemic, trust is critical to the success of a public health response.