Six cases of mumps were reported to MDH during 2005; a total of 29 mumps cases were reported between 2000-2005. All six cases were reported between October and December.
Four (67%) of the case-patients were white, non-Hispanic females ages 13, 34, 38, and 53 years. One case-patient was a 48-year-old white, non-Hispanic male. The sixth case was a 7-year-old female of unknown race and ethnicity. The 7 and 13-year-old case-patients had a documented history of two doses of mumps-containing vaccine. The 34-year-old had a history of one dose of mumps-containing vaccine. The other three cases had no known history of vaccination for mumps. One adult female case-patient was hospitalized for one day for clinical complications including mastitis and oophoritis; the adult male case-patient had orchitis. Including 2004 and 2005, eight of the 10 cases reported have occurred in adults, highlighting the need to assess the mumps immunization status of adults.
No source case was identified for four of the cases. Three cases were epidemiologically linked, including a 48-year-old index case with no known exposure, a 53-year-old household contact who developed symptoms 15 days after the index case’s onset, and a 38-year-old co-worker of the household contact who subsequently developed symptoms 19 days later.
All six cases were laboratory confirmed by positive mumps IgM serology. Two cases were additionally verified by a demonstrated rise in serum IgG between acute and convalescent specimens. One other case was also confirmed by mumps virus isolation from a throat specimen.
Both IgM and IgG serologic testing as well as viral culture should all be performed on suspect mumps cases. False-positive indirect immunofluorescent antibody (IFA) tests for mumps IgM have been reported, particularly in persons who have been vaccinated for mumps. Mumps can be confirmed by viral culture of buccal swabs, throat swabs, urine, or spinal fluid specimens. Specimens for viral culture should be collected during the first 5 days of illness.
Note: For up to date infromation see: Mumps