Non-mumps Viral Parotitis During the 2014-2015 Influenza Season in the United States

Abstract

Background: During the 2014-2015 US influenza season, 320 cases of non-mumps parotitis (NMP) among residents of 21 states were reported to the Centers for Disease Control and Prevention (CDC). We conducted an epidemiologic and laboratory investigation to determine viral etiologies and clinical features of NMP during this unusually large occurrence.

Methods: NMP was defined as acute parotitis or other salivary gland swelling of >2 days duration in a person with a mumps- negative laboratory result. Using a standardized questionnaire, we collected demographic and clinical information. Buccal samples were tested at the CDC for selected viruses, including mumps, influenza, human parainfluenza viruses (HPIVs) 1-4, adenoviruses, cytomegalovirus, Epstein-Barr virus (EBV), herpes simplex viruses (HSVs) 1 and 2, and human herpes viruses (HHVs) 6A and 6B.

Results: Among the 320 patients, 65% were male, median age was 14.5 years (range, 0-90), and 67% reported unilateral parotitis. Commonly reported symptoms included sore throat (55%) and fever (48%). Viruses were detected in 210 (71%) of 294 NMP patients with adequate samples for testing, ≥2 viruses were detected in 37 samples, and 248 total virus detections were made among all samples. These included 156 influenza A(H3N2), 42 HHV6B, 32 EBV, 8 HPIV2, 2 HPIV3, 3 adenovirus, 4 HSV-1, and 1 HSV-2. Influenza A(H3N2), HHV6B, and EBV were the most frequently codetected viruses.

Conclusions: Our findings suggest that, in addition to mumps, clinicians should consider respiratory viral (influenza) and herpes viral etiologies for parotitis, particularly among patients without epidemiologic links to mumps cases or outbreaks.

Figure 1.

Geographic distribution of viruses detected among patients with non-mumps viral parotitis, with samples tested at the Centers for Disease Control and Prevention, United States, 1 October 2014–31 May 2015. Abbreviations: EBV, Epstein-Barr virus; HHV, human herpes virus; HPIV, human parainfluenza virus; HSV, herpes simplex virus.

Figure 2.

Virus detection among patients with non-mumps parotitis by age group, United States, 1 October 2014–31 May 2015. * Unless otherwise noted, virus detection indicates single detections of a virus in a sample. †Two viruses were codetected in each of 36 samples. The codetection pairings included 19 samples with influenza A(H3N2) virus and human herpes virus 6B (HHV6B) detected, 10 with influenza A(H3N2) virus and Epstein-Barr virus (EBV), 2 with EBV and HHV6B, 2 with influenza A(H3N2) virus and herpes simplex virus1 (HSV-1), 1 with EBV and human parainfluenza virus 2 (HPIV2), 1 with HHV6B and HPIV2, and 1 with HPIV2 and HSV-2. Three viruses were detected in 1 sample: influenza A(H3N2) virus, EBV, and HHV6B. ^‡ Other respiratory viruses include HPIV2 detected in 5 samples, HPIV3 detected in 2 samples, and adenovirus detected in 3 samples. Abbreviations: EBV, Epstein-Barr virus; HHV, human herpes virus.