The Avengers just finished fighting Thanos, but now a group of people in California that watched Endgame may be battling measles.

Orange County officials warned Wednesday that a woman with measles apparently saw the opening nights midnight showing of Avengers: Endgame in Fullerton before realizing she was sick.

As a result, she may have exposed others in the region to the highly contagious disease, according to the Los Angeles Times.

The twenty-something patient lives in Placentia and had just returned from a trip to Vietnam, where there has been widespread measles activity, according to Inside Edition.

The woman was unaware she was sick when entered the theater at 11 p.m. Thursday. She didnt leave until 4 a.m. Friday, and she went to the emergency room later Friday.

The woman is now under voluntary isolation at home.

Orange County Health Care agency spokeswoman Jessica Good told the Orange County Register that the the exposure risk applies to anyone who was at the theater during that time period.

As you might expect, theater employees are not thrilled that they and others may have been exposed to measles.

The last place I would ever expect it was at my job. I wasnt even expecting Orange County, AMC Fullerton employee Carlee Greer-McNeill told NBC Los Angeles.

She added: People, if you know you have the measles, please dont come to a movie theater, let alone a public place.

Officials are asking people who were at the following locations to review their vaccination history and also monitor themselves for measles symptoms:

• 5 Hutton Centre Drive, Santa Ana, between 7:45 a.m. and 7:15 p.m. on April 23, 24 and 25.

• AMC movie theater, 1001 S. Lemon St., Fullerton, from 11 p.m. April 25 to 4 a.m. April 26.

• St. Jude Medical Center emergency department, 101 E. Valencia Mesa Drive, Fullerton, from 7 to 9 a.m. April 27.