Coronavirus has now spread to more than 100 countries, representing two-thirds of the world’s population . In Pittsburgh, large events are being canceled; college classes are moving online; and everyone’s taking extra long to wash their hands. Helping explain the headlines this week from the WESA newsroom: Sarah Boden , health and science reporter Ariel Worthy , government and accountability reporter Katie Blackley , digital producer currently covering coronavirus All of the positive cases are