J Med Microbiol 56 (2007), 819-823; DOI: 10.1099/jmm.0.47057-0
© 2007 Society for General Microbiology
ISSN 1473-5644
Pneumococci responsible for invasive disease and discharging ears in children in Sydney, Australia
Michael Watson
,
Maggie Brett,
Mitchell Brown
,
Marianne G. Stewart,
Shirley Warren and
for the New South Wales Pneumococcal Network
The New South Wales Pneumococcal Reference Laboratory, The Children’s Hospital at Westmead, Department of Microbiology, Westmead, New South Wales, Australia
Correspondence
Michael Watson
mwatson{at}clinipath.net
Received 8 November 2006
Accepted 1 February 2007
The serotypes and molecular clones of penicillin-nonsusceptible Streptococcus pneumoniae (PNSP) responsible for invasive pneumococcal disease (IPD) and discharging ears in metropolitan New South Wales were characterized to form a baseline prior to introduction of the heptavalent conjugate pneumococcal vaccine in Australia. Pneumococci isolated between 1 July 2000 and 30 June 2003 in Sydney from children <15 years were tested for antibiotic susceptibilities and serotyped. Penicillin-nonsusceptible pneumococci were typed by multilocus sequence typing and BOX PCR. During this period, 97 (13.9 %) of 698 pneumococci from IPD that were serotyped were penicillin-nonsusceptible. Of 607 pneumococci from discharging ears, 157 (26.1 %) were penicillin-nonsusceptible. Serotype 14 was the predominant serotype responsible for IPD and serotype 19F predominated from discharging ears. The heptavalent vaccine serotypes accounted for 613 (87.8 %) of all invasive isolates and 420 (69.8 %) of all isolates from discharging ears. Representatives of the major international clones were present among the PNSP. The majority of serotypes and clones that showed penicillin-nonsusceptibility are present within the vaccine. Serotype switching was also noted to have occurred prior to introduction of the vaccine. This study provides a characterization of the pneumococcal serotypes associated with IPD and discharging ears that will be useful for detecting potential selective effects of the vaccine. This surveillance should be continued, as it will be important to monitor the frequency and distribution of serotypes in the post-vaccine era.
Abbreviations: IPD, invasive pneumococcal disease; MLST, multilocus sequence typing; PNSP, penicillin-nonsusceptible Streptococcus pneumoniae.
Present address: Clinipath Pathology, 647 Murray St, West Perth, Western Australia, 6005.
Present address: Institute of Clinical Pathology and Medical Research, Westmead Hospital, New South Wales, Australia.
Members listed in Acknowledgements.
Copyright © 2007 Society for General Microbiology.
