title: Epidemiology of acute otitis media caused by Streptococcus pneumoniae before and after licensure of the 7-valent pneumococcal protein conjugate vaccine.
abstract: We studied, by pulsed-field gel electrophoresis, multilocus sequence typing and penicillin-binding protein 2b amplicon-restriction profiles, pneumococcal isolates recovered from children with acute otitis media during 1 January-31 December 1999 and 2001. The proportion of nonvaccine serogroups increased from 14.8% (13/88) to 36.5% (23/63) from 1999 to 2001 (P<.01). Among children who received at least 2 doses of the pneumococcal 7-valent protein conjugate (PNC7) vaccine, 46.7% (7/15) of the isolates had nonvaccine serogroups, compared with 20.8% (26/125) of the isolates from children who did not receive the PNC7 vaccine (P=.05). Overall, the serogroups involved in capsular switching were 6-19-NT, 6-14-35, 15-19, and the 19-Spanish 23F clone. In 1999 and 2001, 30.8% (4/13) and 26.1% (6/23) of the nonvaccine serogroups were implicated in capsular switching, respectively. Continued surveillance will be of great importance as the distribution of the PNC7 vaccine increases.
authors.affiliation: Division of Infectious Diseases, University of Pittsburgh School of Medicine and Graduate School of Public Health, Pittsburgh, Pennsylvania 15213-2582, USA.
authors.forename: M Catherine
authors.initials: MC
authors.lastname: McEllistrem
authors.forename: Jennifer
authors.initials: J
authors.lastname: Adams
authors.forename: Edward O
authors.initials: EO
authors.lastname: Mason
authors.forename: Ellen R
authors.initials: ER
authors.lastname: Wald
mesh_terms: D000208:Acute Disease; D001426:Bacterial Proteins / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D002648:Child; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006602:Hexosyltransferases / Q000235:genetics; D006801:Humans; D008297:Male; D022401:Meningococcal Vaccines / Q000276:immunology*; D002267:Muramoylpentapeptide Carboxypeptidase / Q000235:genetics; D010033:Otitis Media / Q000382:microbiology* / Q000517:prevention & control; D046915:Penicillin-Binding Proteins; D010458:Peptidyl Transferases / Q000235:genetics; D011008:Pneumococcal Infections / Q000382:microbiology* / Q000517:prevention & control; D022242:Pneumococcal Vaccines / Q000276:immunology*; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification*
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D022401:Meningococcal Vaccines; D046915:Penicillin-Binding Proteins; D022242:Pneumococcal Vaccines; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D002267:Muramoylpentapeptide Carboxypeptidase