J Med Microbiol 57 (2008), 480-487; DOI: 10.1099/jmm.0.47690-0
© 2008 Society for General Microbiology
ISSN 1473-5644
Invasive pneumococcal disease: epidemiology in children and adults prior to implementation of the conjugate vaccine in the Oxfordshire region, England
Dona Foster1,2,
Kyle Knox3,
A. S. Walker4,
D. T. Griffiths1,
Hazel Moore1,
Elizabeth Haworth2,
Timothy Peto4,
Angela B. Brueggemann5,
Derrick W. Crook1 and
on behalf of the Oxford Invasive Pneumococcal Surveillance Group
1 Nuffield Department of Clinical Laboratory Science, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
2 Thames Valley Health Protection Unit, Health Protection Agency, Oxford, UK
3 Division of Public Health and Primary Health Care, University of Oxford, Headington, Oxford OX3 7LF, UK
4 Nuffield Department of Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
5 Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
Correspondence
Derrick W. Crook
derrick.crook{at}ndcls.ox.ac.uk
Received 12 October 2007
Accepted 21 December 2007
A 10-year invasive pneumococcal disease (IPD) enhanced surveillance project in the Oxfordshire region of the UK between 1996 and 2005 identified a total of 2691 Streptococcus pneumoniae isolates from all ages that provided a comprehensive description of pneumococcal epidemiology. All isolates were serotyped and those from children under 5 years of age were genotyped and a matched case–control study using adults hospitalized between 1995 and 2000 was performed to estimate the effectiveness of the pneumococcal polysaccharide vaccine in the local population. Fifty-one serotypes were isolated, with different age distributions. The overall incidence of IPD was 9.2 cases per 100 000 population per annum [95 % confidence interval (CI), 8.6–9.9] and that of meningitis was 0.7 per 100 000 population per annum (95 % CI 0.5–0.9). After adjusting for age, serotype 1 was found to be less likely to be associated with meningitis versus other IPD, compared with the most common serotype 14, whereas serotype 12F was more likely to cause meningitis than other IPD. There were significant temporal changes in IPD incidence of four serotypes, with decreases in serotypes 1, 12F and 14 and increases in serotype 8. A possible novel variant (from serotype 6A to 6B) was found using multilocus sequence typing analysis. From the matched case–control study of adults, the pneumococcal polysaccharide vaccine effectiveness was estimated to be 43 % (2–68 %), which did not change significantly after adjustment for pre-existing co-morbidities. The data provide a baseline against which the impact of the pneumococcal conjugate vaccine introduced in the UK in 2006 could be measured.
Abbreviations: CI, confidence interval; IPD, invasive pneumococcal disease; MLST, multilocus sequence typing; OR, odds ratio; PCV7, pneumococcal conjugate vaccine 7-valent; PPV23, pneumococcal polysaccharide vaccine 23-valent; ST, sequence type.
Tables showing serotype-specific frequency over the study period and MLST profiles of isolates from children under 5 years of age are available as supplementary material with the online version of this paper.
Copyright © 2008 Society for General Microbiology.
