Officials at Arkansas Department of Health are investigating a possible outbreak of mumps that is being reported in more than 30 schools in the state and affecting more than 400 residents.

So far, the health department is investigating a total of 427 suspected cases of mumps. There are currently 13 workplaces and three school districts still impacted by the outbreak. According to the updated report of Arkansas Health Department, 24 schools in Springdale have reported one or more students contracting the mumps virus. Additionally, seven schools in Rogers and one school in Bentonville have similar reported cases.

According to the Centers for Disease Control and Prevention, mumps is a contagious disease caused by a virus. Typical symptoms of mumps include few days of fever, headache, muscle aches, tiredness and loss of appetite. Patients with mumps can be usually distinguished by their puffy cheeks or jaw caused by swollen salivary glands. Severe cases of mumps could lead to swelling in the brain and testicles or ovaries.

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To prevent further outbreak of the disease, Arkansas Health Department is requiring students with vaccine exemptions for the MMR (Mumps, Measles and Rubella) who are attending schools with reported cases of mumps to be excluded from school for 26 days from the date of exposure and until the outbreak is over.

Additionally, the health department is advising parents to have their children received MMR vaccine. Children under six years of age are recommended to have the first dose of the vaccine at age 12 to 15 months followed by the second dose at age four to six years old.

Children age seven to 18 years that did not receive MMR vaccine yet are advised to receive the first dose of the vaccine immediately, followed by the second dose at least four weeks after the initial dose. Adults who are born in 1957 or later are also advised to receive their initial MMR vaccine followed by the second days 28 days later. People born before 1957 are generally considered to be immune to mumps and do not need to receive the MMR vaccine. Two doses of MMR vaccine is proven to be 88 percent effective in preventing mumps.

The health department noted that the MMR vaccine is a live virus and should not be received by pregnant women and people with weakened immune system.