Antimicrobial resistance in Streptococcus pneumoniae has increased in recent decades. We linked two surveillance programs to evaluate trends in incidence, serotype distribution, and antimicrobial resistance in invasive pneumococcal disease (IPD) since the heptavalent pneumococcal conjugate vaccine (PCV7) was introduced in BC in 2003.

Two major outbreaks of invasive meningococcal disease serogroup C (IMD-C) were identified in British Columbia between 2000 and 2004. Pulsed-field gel electrophoresis (PFGE) and porA gene sequencing of all retained IMD-C isolates were used to assess correlations between genotypes and epidemiological patterns. PFGE patterns of IMD-C genotypes correlated with epidemiological patterns between 2000 and 2004 in British Columbia, and demonstrated that PFGE can identify outbreak-related cases. Both IMD-C outbreaks correlated with a respective PFGE pattern. PFGE analysis demonstrated that the 2004 British Columbia outbreak strain in men who have sex with men was closely related to the 2001 Abbotsford outbreak strain. PorA sequencing data indicated low diversity of class 1 outer membrane proteins in British Columbia, and did not correlate with epidemiological trends. There was a trend for outbreak-associated PFGE types to demonstrate higher case fatality rates.

BACKGROUND: This study examined the epidemiology, antibiotic susceptibility and serotype distribution ofStreptococcuspneumoniaeassociated with invasive pneumococcal disease (IPD) in British Columbia.METHODS: Six hospitals and one private laboratory network participated in a prospective, sentinel laboratory based surveillance study of IPD, between October 1999 and October 2000. At each site,S pneumoniaeisolates were collected and epidemiological data were gathered using a structured questionnaire, for all cases of IPD meeting the study case definition. Isolates were serotyped and tested for antimicrobial susceptibility. Bivariate associations were analyzed and multivariate logistic regression was used to identify independent risk factors associated with hospitalization or death.RESULTS: One hundred three reports and isolates were collected. Seventy-nine per cent of cases were community-acquired, 64% required hospitalization and 5% died. Cases with one or more assessed risk factor for IPD and of female sex were independent variables associated with hospitalization or death. One-third of isolates had reduced penicillin susceptibility and 96% of these represented serotypes contained in the 23-valent pneumococcal polysaccharide vaccine (PPV-23). Overall, 89% of serotypes identified are included in the PPV-23 vaccine and 88% of isolates from children under five years of age are found in the 7-valent pneumococcal conjugate vaccine (PCV-7). Forty-one per cent of cases qualified for publicly funded pneumococcal vaccine and 34% of eligible persons were vaccinated.CONCLUSIONS: Overall, pneumococcal serotypes associated with IPD in this study closely matched serotypes included in PPV-23 products currently licensed in Canada. Most serotypes associated with IPD in children under five years of age are included in a recently licenced PCV-7. One third of isolates demonstrated reduced penicillin susceptibility, most involving serotypes included in PPV-23. Effective delivery of current public health immunization programs using PPV-23 and extending protection to infants and young children using the PCV-7 will prevent many cases of IPD.

During 2001, an outbreak of serogroup C meningococcal disease led to immunization of individuals aged 13-29 years in Abbotsford, British Columbia, Canada. This study addresses the distribution of Neisseria meningitidis carriage in this population and the implications of that distribution for the targeting of the immunization campaign. Pharyngeal swabs were obtained at immunization from 2004 people. Colonies were identified and serogrouped using standard agglutination methods and by PCR. Isolates were characterized using pulsed-field gel electrophoresis (PFGE). The prevalence of N. meningitidis carriage was 153 carriers per 2004 subjects (7.6%; 95% confidence interval, 6.5%-8.9%). Only 6 (4%) of the isolates from these carriers were found to be serogroup C by agglutination or PCR testing, and all of these were from individuals within the age group targeted for immunization. Only 1 of these 6 isolates was found to be identical to the outbreak strain by PFGE. The observation that a virulent strain is not circulating widely suggests the possibility of low background immunity in the population at risk and emphasizes the importance of vaccination in controlling epidemic group C meningococcal disease.

ABSTRACT Data from four recent studies (S. H. Goh et al., J. Clin. Microbiol. 36:2164–2166, 1998; S. H. Goh et al., J. Clin. Microbiol. 34:818–823, 1996; S. H. Goh et al., J. Clin. Microbiol. 35:3116–3121, 1997; A. Y. C. Kwok et al., Int. J. Syst. Bacteriol. 49:1181–1192, 1999) suggest that an approximately 600-bp region of the chaperonin 60 (Cpn60) gene, amplified by PCR with a single pair of degenerate primers, has utility as a potentially universal target for bacterial identification (ID). This Cpn60 gene ID method correctly identified isolates representative of numerous staphylococcal species and Streptococcus iniae , a human and animal pathogen. We report herein that this method enabled us to distinguish clearly between 17 Enterococcus species ( Enterococcus asini , Enterococcus rattus , Enterococcus dispar , Enterococcus gallinarum , Enterococcus hirae , Enterococcus durans , Enterococcus cecorum , Enterococcus faecalis , Enterococcus mundtii , Enterococcus casseliflavus , Enterococcus faecium , Enterococcus malodoratus , Enterococcus raffinosus , Enterococcus avium , Enterococcus pseudoavium , Enterococcus new sp. strain Facklam, and Enterococcus saccharolyticus ), and Vagococcus fluvialis , Lactococcus lactis , and Lactococcus garvieae . From 123 blind-tested samples, only two discrepancies were observed between the Facklam and Collins phenotyping method (R. R. Facklam and M. D. Collins, J. Clin. Microbiol. 27:731–734, 1989) and the Cpn60 ID method. In each case, the discrepancies were resolved in favor of the Cpn60 ID method. The species distributions of the 123 blind-tested isolates were Enterococcus new sp. strain Facklam (ATCC 700913), 3; E. asini , 1; E. rattus , 4; E. dispar , 2; E. gallinarum , 20; E. hirae , 9; E. durans , 9; E. faecalis , 12; E. mundtii , 3; E. casseliflavus , 8; E. faecium , 25; E. malodoratus , 3; E. raffinosus , 8; E. avium , 4; E. pseudoavium , 1; an unknown Enterococcus clinical isolate, sp. strain R871; Vagococcus fluvialis , 4; Lactococcus garvieae , 3; Lactococcus lactis , 3; Leuconostoc sp., 1; and Pediococcus sp., 1. The Cpn60 gene ID method, coupled with reverse checkerboard hybridization, is an effective method for the identification of Enterococcus and related organisms.

ABSTRACT It was recently reported that Streptococcus iniae , a bacterial pathogen of aquatic animals, can cause serious disease in humans. Using the chaperonin 60 (Cpn60) gene identification method with reverse checkerboard hybridization and chemiluminescent detection, we identified correctly each of 12 S. iniae samples among 34 aerobic gram-positive isolates from animal and clinical human sources.