Underreporting of viral encephalitis and viral meningitis, Ireland, 2005-2008

• Published in: Emerging infectious diseases Vol. 19; no. 9; pp. 1428 - 1436
• Main Authors: Kelly, Tara A, O'Lorcain, Piaras, Moran, Joanne, Garvey, Patricia, McKeown, Paul, Connell, Jeff, Cotter, Suzanne
• Format: Journal Article
• Language: English
• Published: United States U.S. National Center for Infectious Diseases 01.09.2013; Centers for Disease Control and Prevention
• Subjects: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; aseptic meningitis; Child; Child, Preschool; Disease Notification - statistics & numerical data; Encephalitis, Viral; Encephalitis, Viral - diagnosis; Encephalitis, Viral - epidemiology; Female; herpesviruses; Hospitalization; Humans; Incidence; Infant; Infant, Newborn; Ireland - epidemiology; Male; Meningitis, Viral - diagnosis; Meningitis, Viral - epidemiology; Middle Aged; Sentinel health events; Statistics; varicella-zoster; Viral encephalitis; Viral Encephalitis and Meningitis, Ireland; Viral meningitis; viruses; Young Adult; Ireland; viruses; ICD-10; enterovirus; hospitalization; viral meningitis; Viral encephalitis; disease notification; varicella-zoster; herpesviruses; surveillance; aseptic meningitis
• ISSN: 1080-6040; 1080-6059
• DOI: 10.3201/eid1909.130201

Viral encephalitis (VE) and viral meningitis (VM) have been notifiable infectious diseases under surveillance in the Republic of Ireland since 1981. Laboratories have reported confirmed cases by detection of viral nucleic acid in cerebrospinal fluid since 2004. To determine the prevalence of these diseases in Ireland during 2005-2008, we analyzed 3 data sources: Hospital In-patient Enquiry data (from hospitalized following patients discharge) accessed through Health Intelligence Ireland, laboratory confirmations from the National Virus Reference Laboratory, and events from the Computerised Infectious Disease Reporting surveillance system. We found that the national surveillance system underestimates the incidence of these diseases in Ireland with a 10-fold higher VE hospitalization rate and 3-fold higher VM hospitalization rate than the reporting rate. Herpesviruses were responsible for most specified VE and enteroviruses for most specified VM from all 3 sources. Recommendations from this study have been implemented to improve the surveillance of these diseases in Ireland.