The U.S. saw its largest single-day increase in nearly nine months Friday.
The United States is facing a COVID-19 surge this summer as the more contagious delta variant spreads.
More than 613,000 Americans have died from COVID-19 and over 4.2 million people have died worldwide, according to real-time data compiled by the Center for Systems Science and Engineering at Johns Hopkins University.
Just 57.9% of Americans ages 12 and up are fully vaccinated against COVID-19, according to data from the Centers for Disease Control and Prevention.
The CDC on Tuesday, citing new science on the transmissibility of the delta variant, changed its mask guidance to now recommend everyone in areas with substantial or high levels of transmission -- vaccinated or not -- wear a face covering in public, indoor settings.
Nevada is implementing an indoor mask mandate in counties with substantial or high transmission. The mandate includes Clark County, home to Las Vegas, and Sin City’s casinos and hotels.
The emergency directive, a result of the new CDC guidance, goes into effect Friday, state officials said.
-ABC News’ Alex Stone
Following the new CDC guidance, the Capitol attending physician is recommending that senators and U.S. Senate staff wear face masks.
-ABC News’ Trish Turner
The director of the Centers for Disease Control and Prevention, Dr. Rochelle Walensky, spoke to “Good Morning America” Wednesday about why the CDC has reversed its guidance on masks for vaccinated people.
She said the agency felt it was important that vaccinated Americans “understand that if they happen to be one of those breakthrough infections, which was more likely in areas with a huge amount of transmission and disease, that those people could potentially pass it on to somebody, a loved one, who is immunosuppressed.”
Walensky said the mask guidance was changed because of the “new science that demonstrated for those who are vaccinated, that they could in fact transmit if they are one of those rare breakthrough infections.”
The Office of the Attending Physician is now requiring all members and staff to wear “medical-grade” masks throughout the House of Representatives unless members are speaking in the hall of the House or individuals are alone.
Members and staff will once again be prohibited from stepping on the floor to vote without a mask, or risk incurring fines.
The new guidance follows the CDC’s latest recommendations and will not be in effect on the Senate side.
-ABC News' Ben Siegel
