was airborne in may of last year dr walensky announced that vaccinated people could take masks off indoors and outdoors just weeks later it became clear that vaccinated people could not only get breakthrough infections but also could transmit the virusin august dr walensky joined president biden in supporting booster shots for all americans before scientists at the food and drug administration or her own agency had reviewed the data on whether they were neededmore recently the highly contagious omicron variant has led the cdc to issue recommendations based on what once would have been considered insufficient evidence amid growing public concern about how these guidelines affect the economy and educationin december the cdc shortened the isolation period for infected americans to five days although it appears that many infected people can transmit the virus for longer over the past few weeks some experts have criticized the agency for changing the metrics used to assess risk and determine appropriate local measures in order to appease business and political interestssupporters of dr walensky say that the agency has been handed an extraordinary task and that the cdc is doing its best under extremely difficult circumstances not least that most employees have been working remotelyin a separate statement issued to the public on monday dr walensky said that never in its 75 year history has cdc had to make decisions so quickly based on often limited realtime and evolving sciencewhen asked at a news conference on tuesday whether the call for the review came from the white house the press secretary jen psaki said it had not and was driven by the cdc calling it certainly one we support