FRESNO, Calif. (KFSN) -- Health officials issued a warning after a confirmed case of measles was in Fresno County.
The Los Angeles County of Public Health is now confirming that an infected passenger flew aboard United Airlines flight 5591.
That flight from Los Angeles arrived in Fresno on May 19.
FlightAware tracking data shows the flight, operated by SkyWest Airlines, landed at 8:12 PM and parked at Gate 11.
Action News spoke by phone with a passenger who was on board. She asked us not to use her name.
"I'd say it was probably about 70% full," she said. I mean, there were vacant seats."
It is unclear if the infected passenger is still in Fresno or where the person sat on the plane.
Now, the president of the National Foundation for Infectious Diseases is urging caution.
"Measles is a terrible disease," National Foundation for Infectious Diseases President Patsy Stinchfield said.
"So, everyone, anyone who gets measles will be miserable."
Stinchfield says measles is caused by a virus and has no known treatment or medicine.
Symptoms include a runny nose, fever, and watery eyes. Stinchfield says people with measles are often sensitive to light. There is also a rash.
"It starts about the hairline, moves down the face, down the trunk, and then clears the same pattern," Stinchfield said. "So, it will clear on your face first."
Measles is not usually deadly, but Stinchfield says it is serious.
"This is a very contagious and very serious virus," she said. "It's more contagious than COVID or influenza."
In recent years, more and more Americans with the disease are going to the hospital and are there for about a week.
The U.S. said it eliminated measles in 2000 but never entirely eradicated it. The CDC reports nearly 150 cases so far this year.
There is an effective vaccine that has been in wide use since the 1960s. Most people get it when they are young. California requires it before kids enroll in school.
The passenger we spoke with is now checking her immunity.
"If you do not have access to your vaccination records ... you can get a titer, which is basically a blood test that determines if you have immunity in your system," she said.
Stinchfield says vaccinated passengers on the United flight do not need to worry, but unvaccinated passengers should take precautions.
"Anyone who did have an exposure ... will need to basically stay home and away from public or other family members, school, work - for that 21-day period until that June 9th date," Stinchfield said.
If you were on the United flight, it is too late to get vaccinated.
However, there is still time to prepare for summer travel and consult with your doctor.
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