One case of mumps has been confirmed and an additional 3 associated probable mumps cases have been reported in 4 adults in Dallas. Exposure to mumps likely occurred during a Halloween party which took place on October 29th 2016 in the 75219 zip code. Symptoms have included fever, and parotitis or orchitis, with onset of illness for most cases between November 16-18th. Since additional associated cases may continue to be identified, healthcare providers are reminded to consider mumps in the differential diagnosis of patients with compatible clinical features.
Mumps is transmitted by direct contact with respiratory droplets or saliva, with a usual incubation period of 16-18 days (range 12-25 days) after exposure. Acute parotitis lasting for more than 2 days is a typical manifestation of mumps, and occurs in over 30% of infected persons following a febrile prodrome. Up to 20% of mumps infections are asymptomatic. Complications of mumps can include deafness, orchitis, oophoritis, pancreatitis, and meningoencephalitis. Mumps can occur even in vaccinated persons, since 2 doses of mumps vaccine are ~88% effective at preventing disease.
Maintaining high two-dose community coverage with MMR vaccination remains the most effective way to prevent mumps outbreaks. All school-aged children, college students, international travelers, and health-care personnel should have documentation of 2 doses of MMR vaccine, unless they have other evidence of mumps immunity (e.g. past laboratory-confirmation of disease or mumps-specific IgG antibody). Other unvaccinated adults born in 1957 or later should have documentation of at least one dose of MMR vaccine.