The Centers for Disease Control and Prevention (CDC) announced updated guidance that unvaccinated students who are considered close contacts with a positive COVID-19 case do not need to quarantine, if they consistently test negative for the virus. The new directive was announced by CDC Director Rochelle Walensky, who cited several studies for the decision, during a White House-hosted briefing on Friday. Before Walensky’s announcement, the agency recommended all unvaccinated students who are close contacts to quarantine. “These studies demonstrate that ‘test to stay’ works to keep unvaccinated children in school safely,” Walensky said, while calling it “an encouraging public health practice to help keep our children in school.” The studies she cited showed decreased absences in schools that used test-to-stay policies. One paper, which used research involving about 90 schools in Lake County, Illinois, suggested the strategy eliminated about 8,000 missed school days. The test-to-stay protocol, in another study, prevents …