The measles outbreak that began in Disneyland is still spreading, most recently to Harkins Theater in Chino Hills. Since December 2014, California measles cases have made up 103 of the 155 total national cases.

Locally, an infected individual visited Harkins Theater in Chino Hills on Jan. 17 for three hours, according to San Bernardino County’s Department of Public Health. The theater management refused to comment when asked if any extra precautions had been taken to prevent further spread of measles. The threat of the disease had no effect on business and customers continued to line up to buy tickets.

“This is the first I’m hearing about it, so it’s kind of alarming, but I’d still go to Disneyland, I’d still go to the theaters,” Evan Ennabe, a patron of Harkins Theater, said when speaking to a CBS reporter.

Montclair Plaza is also believed to have been exposed to the disease on Jan. 16.The DPH is now working with the theater and mall to contact anyone who may have been infected.

The U.S. Centers for Disease Control and Prevention said its analysis shows that the virus causing the outbreak is identical to the virus that caused an outbreak of over 21,000 substantiated cases in the Philippines in 2014. They believe the Disneyland outbreak began when a traveler who was infected with measles overseas visited. Of the confirmed cases, 42 are linked to an exposure at Disneyland or Disney California Adventure Park in Anaheim, where the outbreak began in December.

Furthermore, health officials reported that 28 more cases were caused by individuals coming into close contact with the initial group from Disneyland. However, the direct cause of nearly one-third of the total cases in California is unknown.

Those with the infection develop cold-like symptoms before a rash appears on their skin. The individuals are infectious four days prior to and following the appearance rash. While the highly contagious disease is mostly airborne, it can also live on surfaces for nearly two hours, leaving public spaces extremely vulnerable to the disease.

According the California Department of Public Health, vaccination is extremely important and the only way to prevent the spread of measles. However, many parents choose not to vaccinate their children.

Already identified in 16 states, this measles outbreak is on track to surpass the 644 cases in the U.S. in 2014, the highest number since measles were declared eliminated in the U.S. in 2000.