The Brief Snohomish County’s measles outbreak has grown to six confirmed cases, all involving unvaccinated children. Six: that's the number of measles cases in Snohomish County as officials confirmed three new cases and track what they're calling an outbreak. The number of confirmed measles cases in the Snohomish County outbreak has grown again, now to six. The backstory:The latest case of the highly contagious disease was confirmed on Tuesday, according to Snohomish County health leaders. A map of Snohomish County measles outbreak exposure locations.