Massachusetts reports 13th human West Nile virus case this year
A thirteenth human case of West Nile virus has been identified in Massachusetts this year, state public health officials announced Friday . The new case is a woman in her 40s who was likely exposed in Middlesex County. 9, the West Nile virus risk level is high in Boston, Brookline, Cambridge, Chelsea, Everett, Malden, Newton, Revere, Somerville, Watertown and Winthrop, state health officials said.