The Centers for Disease Control and Prevention has extended the nationwide mask mandate for public transport by 15 days, from April 18 to May 2 in light of the emergence of the BA.2 Omicron subvariant that makes up the majority of COVID cases in the U.S. right now. “In order to assess the potential impact the rise of cases has on severe disease, including hospitalizations and deaths, and health care system capacity, the CDC order will remain in place at this time,” the agency said. Recent weeks have seen daily confirmed cases nationwide rise from about 25,000 per day to more than 30,000, though experts say these figures are likely an undercount since many Americans are testing positive with at-home tests that aren’t necessarily reported to public health agencies. As of April 9, the seven-day average of COVID-19 cases in the U.S. was up 10 percent from the week earlier at 28,339, with BA.2 accounting for 85.9 percent of infections.