Mask up, CDC tells fully vaccinated US citizens

The American infectious disease agency Centre for Disease Control (CDC) has urged fully vaccinated people living in substantial and high transmission areas to wear masks indoors. This is a major reversal in guidance that underscored USA's struggle to suppress the Delta variant.

President Joe Biden said the announcement showed that America needs to "do better" on vaccinations, adding that a vaccine mandate for the country's more than two million federal workers was now "under consideration."

Centers for Disease Control and Prevention director Rochelle Walensky cited new data that shows rare breakthrough cases involving Delta have an increased risk of onward transmission.

"In areas with substantial and high transmission, CDC recommends fully vaccinated people wear masks in public indoor settings," she said.

Till last week, the CDC had defended its decision that said that vaccinated people didn't have to wear masks indoors. White House has also told its staff to mask up again due to local transmission rates.

According to the latest CDC data, 63 percent of the country's more than 3,200 counties are experiencing substantial or high transmission.

Substantial is defined as being between 50 to 100 daily cases per 100,000 people over seven days, while high is defined as more than 100 daily cases per 100,000 over seven days.

Biden said he would lay out new steps on Thursday to overcome the lag in vaccinations after the country's strong start to its program.

(With inputs from agencies)