Transcript for Quarantine orders issued at UCLA
And we begin with that breaking news in the measles outbreak, spreading across this country. The worst in 25 years. And tonight, hundreds of students am faculty at two major universities in Los Angeles are under quarantine. There are now cases in 22 states. Look at the map right there. How are the latest cases exposed? ABC's chief national correspondent Matt Gutman starts us off in L.A. Reporter: Tonight, that measles scare racing through two of the biggest university systems in the country. Many dozens possibly exposed to what is considered one of the world's most contagious viruses. We have five cases, four of which are linked as an outbreak. That stemmed from a traveler who was unvaccinated. Reporter: That traveler, coming in from abroad, apparently going through los Angeles airport, one of the busiest in the world, on April 1st, and then going onto UCLA with its 45,000 students, to the psychology department on three days in early April. A few of the cases have been in other places, attending UCLA classes, as well as being at Cal state-l.a. In the library. And as a result of that, we have a high number of contacts that may have been exposed. Reporter: That Cal state library, one of the most visited spots on campus. 2,000 visitors a day and most don't sign in or out. So, we've had a lot of exposure to folks that we actually can't identify. Reporter: Over 300 students and faculty now under quarantine at the two universities with no access to public areas or dorms. If they are not immune to measles, then they must be kept away from others in order to not have that unintentional spread of measles, should they come in contact with others who may not be immune, as well. And Matt Gutman joins us live how what does it mean for all these people, because this is a massive amount of people right now. Reporter: Measles is an exquisitely contagious virus. It can linger in the air for two hours, sometimes more. It's incubation period time, Tom, is 21 days. Some will be able to quickly produce their medical records, likely those younger students, but some of the older faculty may have a harder time finding them and they could stay in quarantine for up to two more weeks. Matt Gutman with that breaking news tonight. Matt, thank you.
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