The order was issued at UCLA and Cal State LA for students and staff who have been exposed to a confirmed case of measles and who can not demonstrate that they have been vaccinated against the highly contagious disease.
Those Students and college students over 100 have been told to stay at home, avoid contact with others, and notify health authorities when symptoms occur.
"Both universities are helping implement quarantine orders and are best-placed to help those who need to be quarantined and campus-based," said Los Angeles County Department of Public Health.
The US Centers for Disease Control and Prevention confirmed the milestone on Wednesday. The agency counted 695 cases in 22 states this year.
A Los Angeles Health Department statement stated that the measures will be implemented at the two universities to "educate students, faculty and staff about the risks of measles after possible exposure to mastication".
"Measles quarantine can last up to 21 days from the date of the last exposure, at which time the exposed person is no longer at risk of developing the disease and spreading measles to other people," the statement said.
Measles are a highly contagious disease caused by a virus that can spread through the air when an infected person coughs or sneezes, or someone comes into direct contact or by germs by touching the same objects or surfaces. The symptoms of measles include fever, cough, runny nose, watery eyes and a rash of red spots.
Measles can remain in the air for up to two hours after a sick person coughs or sneezes, and they can spend many hours on the surface. This makes a college campus particularly vulnerable to the spread of the disease, as many people go in and out of buildings.
In a letter to students and faculty, UCLA Chancellor Gene Block said that the university had been told Monday that a student was getting measles. The student attended the classes at Franz Hall and Boelter Hall for three days – April 2, 4, and 9 – while he was contagious, Block said.
"When UCLA heard about this incident, he immediately identified more than 500 students, faculty, and staff the student might have come in contact with or had otherwise been exposed to," Block said. "They were also informed in detail about treatment and prevention."
Most people have been evicted, "said the chancellor," but we still have medical records from 119 students and eight faculty members to see if they are immune to the measles. "
"We expect notifying parties to be quarantined for approximately 24 to 48 hours until proof of immunity is established," said Block. "Some may need to stay quarantined for up to seven days, and we have arranged for those living on campus to be looked after during the quarantine at UCLA."
In Cal State, LA, school officials said that measles could have been exposed at the North Library on 11 April between 11am and 3pm.
Library staff, including student employees, "were sent home under quarantine orders and instructed to stay home and avoid contact with other people as much as possible," the university said.
The university did not specify how many people were affected by the quarantine.
"The Department of Health has determined that there is currently no known current risk for measles in the library," the university said.
Meanwhile, state health officials urged Californians on Thursday to ensure that they were vaccinated against measles before traveling, especially at international locations.
The number of measles cases in California more than doubled from 15 to 38 in the past week, said the California Department of Health. Last year there were a total of 11 cases.
Of the 2019 cases, 14 were for international travelers, 22 were to be transferred from travelers to persons in California, and two cases are of unknown origin, according to the Agency.
Health officials also said that a passenger who flew in and out of Los Angeles International Airport on April 18 was confirmed with a measles case, the fourth such case at the airport.
"Vaccination is the only way to make sure that you and your family members do not get measles," Dr. Karen Smith, director of the California Department of Health. "Measles are widely used in many countries so make sure you and your family are fully vaccinated before traveling internationally."