"We've learned more due to research and additional scientific evidence and now we know [that] not only wearing a mask prevents the person wearing the mask to transmit to others, but wearing the mask protects the person who's wearing it," said Dean Blumberg, chief of pediatric infectious diseases at UC Davis Children’s Hospital. "So the wearer of the mask, even the standard rectangular surgical masks...will decrease the risk of infection by the person wearing the mask by about 65 percent."