Centers for Disease Control and Prevention

The US Centers for Disease Control and Prevention added a third measles death to its dashboard this week but declined to reveal which state it occurred in, drawing sharp criticism from infectious disease and legal experts who say the agency is being less transparent than in the past. The decision comes as the outbreak continues to accelerate, with 4,410 confirmed cases so far this year, nearly double last year's count and an 8% increase in a single week.

Pennsylvania has confirmed six measles-associated deaths as its outbreak reached 1,222 cases, up from 86 the week before, and the US Centers for Disease Control and Prevention said it will send a 'disease detective' and nearly $4 million to support the state's response. The CDC reported 4,410 measles cases nationally as of Friday, an increase of 330 in a week.