Medical experts said the U.S. is experiencing its worst mumps outbreak in 10 years.
"It's very scary to know something like this is around," parent Daniel Letoe said.
Parents in multiple states are feeling anxious after top U.S. health officials said they're closely monitoring the largest mumps outbreak in more than a decade.
"What we are seeing is a highly infectious disease moving in a community," said Dr. Jeff Duchin, King County Health.
King County, near Seattle, has reported a growing number of cases. In, at least, five public schools.
Harvard University has been coping with handfuls of infected students since the beginning of the school year.
And over at the University of Missouri more than 200 people have come down with the virus.
The Centers For Disease Control and Prevention said mumps cases have now surfaced in all but three states, with nearly 4,300 infections reported.
Arkansas is the epicenter, with nearly 2,200 cases, in mostly school-aged children.
"What everyone around the state can do is just make sure they're up to date with their immunizations," said Dirk Haselow, Epidemiologist for the state of Arkansas.
Lack of immunizations in general could largely be to blame for the nationwide outbreak, according to public health officials.
Several years ago, rumors circulated that certain vaccines could cause autism in children, while that was later de-bunked. It still terrified many parents to the point of completely opting their kids out of vaccine programs. Something doctors do not recommend to prevent future spread of disease.
"There is no doubt that the number of cases of mumps has decreased dramatically, in the areas we have the mumps vaccine," said Dr. Michael Cooperstock, University of Missouri School of Medicine.
The virus can be extremely contagious since it's transmitted through saliva, capable of spreading with a sneeze or cough. Symptoms can include high fever, swollen cheeks and extreme headaches.
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