SAN FRANCISCO (AP) -- San Francisco Bay Area health officials issued a public warning that a college student with measles could have exposed thousands of others when he attended classes and rode public transit.
The officials said Thursday they had confirmed that the student diagnosed last week was not vaccinated and was likely infected with measles during a recent trip to Asia.
The student in his 20s lives in Contra Costa County and attends classes at the University of California, Berkeley.
The measles virus can stay suspended in the air for up to two hours, said Janet Berreman, a health officer for the city of Berkeley said Friday.
"That can lead it to being very contagious," said Berreman, adding that no other measles infections related to the case have been identified so far.
Kim LaPean, a university health services spokeswoman, said UC Berkeley health officials have contacted about 100 students who were in class with the infected student. The school also has ordered about 300 doses of measles vaccine from the state for any students not vaccinated.
"We'll continue to monitor the demand for the vaccination and may hold a clinic if necessary," LaPean said.
In Southern California, at least 10 elementary school students without complete immunization records in Temecula were sent home Thursday after a student was diagnosed with measles.
Nationally, about 189 people were reported to have measles last year, according to the federal Centers for Disease Control. That figure represented the second-largest number of cases in the U.S. since 2000. About 28 percent of these people got measles in other countries, the CDC said.
Symptoms can begin one to three weeks after exposure and can include high fever, runny nose, coughing and watery red eyes. A rash could develop on the face and neck two to three days after a fever begins and could spread across the entire body, Berreman said.
The rash usually lasts five or six days, she said. An infected person is contagious for several days before and after the rash appears. Serious but rare complications can include ear infections, pneumonia or encephalitis.
"Measles can progress to death, but that has become very rare," Berreman said.
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