Dr. Yasmeen Beg, an assistant professor of anesthesiology at Northwestern Medicine in Chicago, also agrees with the WHO’s advice on masks, at least while indoors. “As the scientific community sorts out the significance of the #delta variant & new #DeltaPlus variant, the community should continue indoor masking especially in crowds/schools,” Beg wrote Sunday on Twitter. (The Delta plus variant is a slightly modified version of the Delta variant spreading in several countries, including the U.K., U.S. and India, CNN reports. Researchers are still trying to learn if it’s more dangerous than other variants.)... “We are already starting to see some consequences of these events with increasing transmission again. The Delta variant will make that epidemic curve exponential,” Dr. Maria Van Kerkhove, an infectious disease epidemiologist and the WHO COVID-19 technical lead, said during the press conference. “So, please, do what you can to keep yourself safe and make decisions individually about what [you] need to do every day.”