title: Viral etiology of mumps-like illnesses in suspected mumps cases reported in Catalonia, Spain.
abstract: We investigated the etiology of reported sporadic suspected mumps cases with a negative RT-PCR result for the mumps virus in the Barcelona-South region in 2007-2011. Samples from mumps virus-negative patients presenting unilateral or bilateral parotitis or other salivary gland swelling were tested for Epstein-Barr virus (EBV) by real-time PCR and for respiratory viruses by two multiplex-PCR-based assays to detect parainfluenza virus (PIV) 1-4, influenza virus (InV) A, B and C, respiratory syncytial virus (RSV), enterovirus, coronavirus 229E, coronavirus OC43, and rhinovirus. 101 samples were analyzed in persons aged 8 months to 50 years. Oral samples were collected on the first day of glandular swelling in 53 patients (52.5%), and on the first two days in 74 patients (73.3%). Viruses were detected in 52 (51.5%) of samples: one virus (25 EBV, 8 PIV3, 4 adenovirus, 4 PIV2, 1 PIV1, 1 InVA, and 1 enterovirus) was detected in 44 patients (84.6%), two viruses in 7 patients, and three viruses in one patient. In 58 patients (57.5%) whose sample was collected in the first 2 days after onset of parotitis and had received two doses of MMR vaccine and in 15 patients (14.8%) whose sample was collected on the first day, it is very likely that the cause was not the mumps virus. This would mean that 72.3% (73/101) of the reported sporadic suspected mumps cases were not mumps cases. The timing of oral-sample collection is crucial to correctly interpret the negative results for mumps virus RNA, especially when suspected cases occur in vaccinated persons.
authors.affiliation: a Epidemiological Surveillance Unit of Health Region, Barcelona-South; Public Health Agency of Catalonia; Hospitalet de LLobregat; Spain.
authors.forename: Irene
authors.initials: I
authors.lastname: Barrabeig
authors.forename: Josep
authors.initials: J
authors.lastname: Costa
authors.forename: Ariadna
authors.initials: A
authors.lastname: Rovira
authors.forename: M Angeles
authors.initials: MA
authors.lastname: Marcos
authors.forename: Ricard
authors.initials: R
authors.lastname: Isanta
authors.forename: Rubén
authors.initials: R
authors.lastname: López-Adalid
authors.forename: Ana
authors.initials: A
authors.lastname: Cervilla
authors.forename: Nuria
authors.initials: N
authors.lastname: Torner
authors.forename: Angela
authors.initials: A
authors.lastname: Domínguez
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D060885:Multiplex Polymerase Chain Reaction; D010309:Parotitis / Q000453:epidemiology* / Q000473:pathology* / Q000821:virology; D060888:Real-Time Polymerase Chain Reaction; D013030:Spain / Q000453:epidemiology; D014777:Virus Diseases / Q000453:epidemiology* / Q000473:pathology* / Q000821:virology; D014780:Viruses / Q000145:classification / Q000302:isolation & purification*; D055815:Young Adult
keywords: MMR vaccine; laboratory diagnosis; mumps virus; parotitis; sample collection timing; suspected cases