RACHEL MARTIN, HOST:
Health officials are racing to contain the spread of measles at two college campuses in Los Angeles. More than 200 university students and staff at UCLA and Cal State LA have been ordered into quarantine after potentially being exposed to the highly contagious disease. This comes after authorities declared a measles outbreak in Los Angeles County earlier this week. According to the CDC, there are now currently 695 reported cases of measles in 22 states. That's the highest number on record since measles was declared eliminated from the U.S. back in 2000. Saad Omer is an infectious disease specialist at Emory University in Atlanta, and he joins us on the line.
Good morning.
SAAD OMER: Good morning.
MARTIN: Los Angeles County Public Health Director Dr. Barbara Ferrer said the following about the quarantine orders at UCLA and Cal State LA. Let's listen.
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BARBARA FERRER: We're offering vaccinations and, where appropriate, we're quarantining those close contacts until they can establish that they're immunized or they're immune or the incubation period for passing along a potential case of measles has passed.
MARTIN: Cal State LA told its exposed students and staff to stay home, avoid contact with anyone. UCLA says it's arranged for students to be cared for at the university while they're quarantined. How - is this what should happen in a case of a necessary quarantine?
OMER: Yes. No, so these are routine measures in the case of an outbreak. And so they're dealing with an outbreak, and they're dealing with an exposure situation in a community where a lot of people come into contact with each other. So these are appropriate measures.
MARTIN: What are the risks at this point?
OMER: So what they're trying to do is to try to minimize the transmission risks for people who haven't developed symptoms yet. And so obviously, those who have developed symptoms are easier to identify. And this virus starts transmitting four days, approximately, before the symptoms appear. So they're trying to put a distance between folks who may not even be symptomatic and others to control the outbreak. So I think they're sort of taking appropriate measures.
MARTIN: But you say that you can have the disease four days before you start to have symptoms, so anyone walking around those campuses could be affected.
OMER: Yeah. So that's the time when they - you can transmit. But it's not everyone. But - they're tracing contacts, etc., who came into contact with the initial...
MARTIN: OK.
OMER: ...Case that they're concerned about. So I think what seems - is that they have the situation being addressed in a reasonable way that you would address in these kinds of things.
MARTIN: UCLA says most of the people will be quarantined between 24 and 48 hours. A few others will need to stay under watch for up to seven days. Why the difference?
OMER: So - you know, when they came into contact with this person but also as - you know, one of the reasons why they do this is that one way of not being into - in quarantine is to provide an evidence of immunity. And so they have certain ways of providing documentation that you have adequate immunity, either through vaccination or through sort of lab testing, etc. So as people provide that documentation, they get cleared as well.
MARTIN: All right. Saad Omer of Emory University in Atlanta - he is an infectious disease specialist.
We appreciate your time this morning, sir. Thank you.
OMER: My pleasure. Transcript provided by NPR, Copyright NPR.