The woman in her 20s, had recently traveled to a country with an outbreak of measles, and didn't know she was afflicted when she went to the showing, the Orange County Health Care agency said, according to NBC4. Hacker said that if someone who does not have the measles vaccination was exposed at the airport, they could get a rash between April 23 and May 7. Health officials say she was at the theater from 11 p.m.to 4 a.m. "I wasn't even expecting Orange County", she said.
Presumably unaware of her condition, the woman appears to have gone to work in Santa Anna for three days, before attending the April 26 midnight screening of Avengers in Fullerton.
An increase in measles cases has been reported throughout the United States.
The woman, whose name was not released, voluntarily quarantined herself at home, according to the HCA. The woman, who had just arrived from an global trip, had somehow exposed other moviegoers to measles between 11 p.m.in the evening until 4 a.m. "And of the nine jurisdictions now experiencing outbreaks in the United States, three of them are in California-and the disease has turned up in 11 counties so far". People with measles can spread the virus before they know they are infected and up to four days before a rash begins to develop.
Surrounding states have reported measles outbreaks in recent months, but this week's case in Allegheny County is the only confirmed case of the measles in Pennsylvania this year.
The woman reportedly lives in Placentia and returned to the USA from a trip to Vietnam, where there is also a widespread measles outbreak, according to The Huffington Post.
People who haven't been vaccinated and those with weakened immune systems are at the highest risk.
Measles is highly contagious, as it is airborne and can spread when an infected person coughs or sneezes. "'The MMR vaccine is a simple, low-cost and very effective measure to prevent the spread of this serious virus'".