Advertisement'A Very Concerning Shift': CDC Head Warns Of Recent Uptick In COVID-19 CasesFebruary 26, 2021Rachel TreismanfacebookEmailCenters for Disease Control and Prevention Director Rochelle Walensky said on Friday that the says that the 7-day average of confirmed cases in the U.S. has ticked up for the past three days, warning that "now is not the time to relax restrictions." (AFP via Getty Images)