(Photo: Joe Raedle, Getty Images)

A doctor prepares to administer a measles vaccination to a child at in Miami. (Photo: Joe Raedle, Getty Images

With as many as 1,000 people across three Arizona counties potentially exposed to the measles, state public-health officials are asking people who think they may have come in contact with the virus to isolate themselves. In addition, they are asking those who may have been exposed not to show up at doctors’ offices, emergency rooms or urgent-care centers, where others could be exposed to the highly contagious virus, which can linger in the air for two hours. Maricopa County Public Health Director Bob England said parents who are concerned about sending their children to school or day care should start asking direct questions. “It is perfectly reasonable to ask their child-care provider or school how many kids in that school are not vaccinated because parents chose not to,” he said. To date, officials have confirmed seven cases of measles: five in Pinal County, two in Maricopa County. In addition, health officials in Gila County are working to identify anyone who might have come in contact with one of the Pinal County patients, who visited a hospital there in mid-January. The possible exposure rate of 1,000 people is tied in large part to those who may have come in contact with 195 children who Maricopa County health officials say were exposed to measles between Jan. 20 and 21 at the Phoenix Children’s East Valley Center in Mesa. More