In the last 20 years, measles cases have been so rare, recollection of the disease may be what people viewed on an episode of "The Brady Bunch."
A sitcom clip has been used by anti-vaccination advocates who say that the inoculations are more dangerous than the disease.
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Now, "Brady Bunch" actress Maureen McCormick is denouncing the use of the clip by those playing down the disease, and she's joining public health officials by urging all to get shots.
"One person with a confirmed case of measles can very easily expose 1,000 people in a four-day period to that measles virus," said Barbara Ferrer, director of Public Health for L.A. County.
Measles outbreak in Southern California: Everything you need to know
It can take four days for an infected person to show any sign of being stricken. There is no treatment and no cure for measles. Potential outcomes are pneumonia, brain inflammation and death.
According to the Centers for Disease Control and Prevention, more than 704 people sickened in 22 states had not been vaccinated. More than 1/3 of the cases are children younger than 5 years old.
The number of confirmed cases remains at five L.A. County residents. One attended UCLA. One attended Cal State, Los Angeles. It was a student who spent time in the main library.
RELATED: Measles outbreak prompts broader quarantines at Cal State LA, UCLA
Because the virus remains in the air for as long as two hours, hundreds of people were exposed.
On Monday, blood tests confirm that nearly 400 at Cal State L.A. were immunized and have been cleared, while 281 remain under orders to stay at home. At UCLA, all but 30 have been cleared.
Credit is going to a policy at UCLA that all incoming students and transfers show proof of immunization, something that's especially important for those who travel internationally.
"This is a safe vaccine, it's highly effective," said Ferrer. "You get two doses. It's 97 percent effective. It's one of the most effective vaccines we have."
Both campuses are looking forward to getting back to their routine as the quarantine period ends Tuesday at UCLA and Thursday at Cal State L.A.