The Arkansas Department of Health is fighting the biggest mumps outbreak in the state in decades.

FOX's Jeff Monosso reports: 

There are 500-cases of the mumps virus involving mostly children and more than 30 school districts in Northwest Arkansas with state health officials mandating that students who have a measles, mumps and rubella vaccine exemption, that they stay home.

The mumps virus, which is known for causing swollen glands in the face and neck and in rare cases severe complications:

(Mirivel) "We believe this one started with travel between Arkansas and Iowa and we've seen an outbreak start in Oklahoma."

State health spokeswoman Meg Mirivel says the MMR vaccine is the most effective way to prevent a mumps infection, along with not sharing saliva or close contact with someone who has the mumps.

Jeff Monosso, FOX News.

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