Delta variant


The spread of the super-contagious Delta variant has prompted new restrictions around the world and spurred stark new warnings from public health officials. “The Delta variant is more aggressive and much more transmissible than previously circulating strains,” Dr. Rochelle P. Walensky, director of the Centers for Disease Control and Prevention, said at a White House briefing last week. “It is one of the most infectious respiratory viruses we know of and that I have seen in my 20-year career.”
The Delta was as transmissible as chickenpox. Although the vaccines continue to provide strong protection against severe disease and death, fully vaccinated people can be infected by, and transmit, Delta, the agency noted. Given these facts, it was time to “acknowledge the war has changed,” the document said.
This week, these observations prompted the C.D.C. to change the recommendations it released in May, which had said that fully vaccinated people did not need to wear masks indoors. The agency now says that in virus hot spots, everyone, regardless of vaccination status, should wear masks in indoor public spaces. It also recommended universal masking in schools this fall.