5 Disneyland employees diagnosed with measles

The happiest place on Earth just got a bit sadder for some of its employees.

Due to a recent measles outbreak, several Disneyland workers are being tested for the virus.

Five employees were diagnosed with measles, and three of them have fully recovered, Disneyland says.

“The measles outbreak exposure period of December 17-20 at the Disneyland Resort is over, and all cases from this exposure should have occurred by January 10, 2015,” the California Department of Public Health says. “No new cases have been identified in guests who visited after that time period.”

Disneyland said it was informed of measles cases among employees on January 15.

Measles is a respiratory disease caused by a virus and spread through the air, according to the Centers for Disease Control and Prevention. Measles starts with a fever, runny nose, cough, red eyes and sore throat, the CDC said.

As for symptoms, “measles starts with a fever, runny nose, cough, red eyes and sore throat,” the CDC says.

The disease outbreak apparently surfaced when visitors reported coming down with measles after visiting the park December 15-20.

Previously, public health officials in California and Utah confirmed nine cases among visitors to either Disneyland or Disney California Adventure Park.

After Orange County health officials notified Disneyland of the measles cases on January 7, “we immediately began to communicate to our cast to raise awareness,” the theme park’s chief medical officer, Dr. Pamela Hymel, said in a statement. Disneyland refers to its employees as cast members.

“In an abundance of caution, we also offered vaccinations and immunity tests,” Disney said. “To date, a few Cast Members have tested positive and some have been medically cleared and returned to work. Cast Members who may have come in contact with those who were positive are being tested for the virus. While awaiting results, they have been put on paid leave until medically cleared.”

It’s not clear how many of the theme park employees were vaccinated.

So far, five children and 13 adults have been diagnosed with measles in Orange County, according to the county health agency.

One school in Huntington Beach has barred children who could not prove that they were vaccinated for measles from going to school until January 29, according to the county health agency.

A highly contagious virus

Those showing measles symptoms shouldn’t be bashful about seeing their doctor, because a full body rash is likely to break out next.

“If you have symptoms, and believe you may have been exposed, please contact your health care provider,” said Dr. Ron Chapman, director of the state health department.

Vaccination is key.

“Two doses of measles-containing vaccine (MMR vaccine) are more than 99 percent effective in preventing measles,” the health department said in a press release. “Measles vaccines have been available in the United States since 1963, and two doses have been recommended since 1989.”

“Travelers to areas where measles is endemic can bring measles back to the U.S., resulting in limited domestic transmission of measles,” read a statement from the California Department of Public Health. “Disney and other theme parks in California are international attractions and visitors come from many parts of the world, including those where measles is endemic.”

5 things to know about measles

CNN’s Kevin Conlon contributed to this report