title: Epidemiological analysis on two decades of hospitalisations for meningitis in the United States.
abstract: Bacterial meningitis is an important source of mortality and morbidity worldwide. Data exist on specific vaccines against Streptococcus pneumoniae and Neisseria meningitidis indicating that they reduce the incidence of meningitis, yet comprehensive information on the trend of bacterial meningitis is still lacking. We analysed the Kids' Inpatient Database and the National Inpatient Database considering all bacterial meningitides in the United States, excluding cases of tuberculosis and sexually transmitted diseases. We analysed the trend of meningitis incidence from 1993 to 2011 and in specific age groups before and after the introduction of the pneumococcal conjugate vaccine 7 (PCV-7) and the meningococcal conjugate vaccine 4 (MCV-4). Moreover, we analysed the prevalence of aetiological agents to assess their changes. We estimated 295,706 cases of meningitis having occurred in the United States and a reduction of the discharge rate of 21 %. We observed a significant reduction in cases of meningitis in children and elderly patients following the introduction of the PCV-7. We also found a reduction in subjects aged 10-14 years, an age span consistent with the introduction of MCV-4, although further analyses based on serotypes data are required to confirm this observation. By contrast, we observed an increased prevalence of cases of staphylococcal and streptococcal meningitides. The introduction of PCV-7 has reduced the incidence and changed significantly the aetiology of bacterial meningitis in the United States during the last two decades.
authors.affiliation: Unit of Clinical Pharmacology, Department of Biomedical and Clinical Sciences, University Hospital "Luigi Sacco", Università di Milano, Via GB Grassi 74, 20157, Milan, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Pellegrino
authors.forename: C
authors.initials: C
authors.lastname: Carnovale
authors.forename: V
authors.initials: V
authors.lastname: Perrone
authors.forename: D
authors.initials: D
authors.lastname: Salvati
authors.forename: M
authors.initials: M
authors.lastname: Gentili
authors.forename: T
authors.initials: T
authors.lastname: Brusadelli
authors.forename: S
authors.initials: S
authors.lastname: Antoniazzi
authors.forename: M
authors.initials: M
authors.lastname: Pozzi
authors.forename: S
authors.initials: S
authors.lastname: Radice
authors.forename: E
authors.initials: E
authors.lastname: Clementi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001419:Bacteria / Q000145:classification / Q000302:isolation & purification; D002648:Child; D002675:Child, Preschool; D005260:Female; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006760:Hospitalization; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D016920:Meningitis, Bacterial / Q000453:epidemiology* / Q000209:etiology; D022401:Meningococcal Vaccines / Q000008:administration & dosage; D008875:Middle Aged; D022242:Pneumococcal Vaccines / Q000008:administration & dosage; D015995:Prevalence; D014481:United States / Q000453:epidemiology; D055815:Young Adult
chemical_list: D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D022401:Meningococcal Vaccines; D022242:Pneumococcal Vaccines
references.citation: JAMA. 2012 Apr 4;307(13):1405-13
references.pmid: 22474204
references.citation: N Engl J Med. 1997 Oct 2;337(14):970-6
references.pmid: 9395430
references.citation: JAMA Pediatr. 2014 Jan;168(1):68-75
references.pmid: 24276262
references.citation: Clin Infect Dis. 2010 Jan 15;50(2):184-91
references.pmid: 20001736
references.citation: JAMA. 1985 Mar 22-29;253(12):1749-54
references.pmid: 3871869
references.citation: N Engl J Med. 2013 Jul 11;369(2):155-63
references.pmid: 23841730
references.citation: N Engl J Med. 2006 Apr 6;354(14):1522-4
references.pmid: 16598050
references.citation: Drugs. 2010 Oct 22;70(15):1973-86
references.pmid: 20883054
references.citation: N Engl J Med. 2009 Jan 15;360(3):244-56
references.pmid: 19144940
references.citation: J Infect Dis. 1990 Dec;162(6):1316-23
references.pmid: 2230261
references.citation: Drugs. 2009;69(18):2577-96
references.pmid: 19943708
references.citation: Clin Infect Dis. 2010 Mar 1;50 Suppl 2:S37-44
references.pmid: 20144015
references.citation: N Engl J Med. 2011 May 26;364(21):2016-25
references.pmid: 21612470
references.citation: Vaccine. 2012 Jan 11;30(3):565-71
references.pmid: 22119925
references.citation: Clin Microbiol Rev. 2012 Jul;25(3):409-19
references.pmid: 22763632
references.citation: Clin Infect Dis. 2005 Mar 15;40(6):899-902
references.pmid: 15736029