Many doctors and nurses and EMS workers expressed fears and frustrations at being asked to wear the less effective surgical masks and at the overall lack of proper masks, gowns and eye gear which imperils their ability to fight the coronavirus and puts their own lives at risk.[258][259] The medical workers are concerned that the shortages have not been addressed by the CDC, whose changing guidance for healthcare over how to stay safe themselves and protect the patients remained unclear and misleading, and that the new recommendations are borne of political expediency instead of science.[258] Mid-March, the CDC changed its guidance from stating earlier that regular surgical masks cannot protect a healthy person from infection to now saying that regular masks are "an acceptable alternative" when examining or treating a coronavirus patient. The change came given the shortages of the N95 masks. The American Nurses Association sent a letter to Congress, saying there is concern "that C.D.C. recommendations are based solely on supply chain and manufacturing challenges," and "that these recommendations do not offer strategies to address the limited manufacturing and supply chain of necessary personal protective equipment."[258] By May 10, at least 36 healthcare workers have died from COVID-19 in California.[260]