Multidrug-resistant North American pulsotype 2 Clostridium difficile was the predominant toxigenic hospital-acquired strain in the province of Manitoba, Canada, in 2006-2007.

The objective of the current study was to determine whether the antimicrobial susceptibility profile or genotype of hospital-acquired isolates of Clostridium difficile differed from isolates causing community-acquired disease. Five hundred diarrhoeal stool samples (one >2 ml sample per patient) from patients across Manitoba, Canada, in 2006-2007 that were reported as C. difficile toxin positive were cultured, resulting in 432 isolates of toxin-positive C. difficile for analysis. Of these 432 isolates, acquisition status could be determined for 235 (54.4%); 182 (77.4%) isolates were hospital acquired and 53 (22.6%) were community acquired. North American pulsotype (NAP) designations based on SmaI PFGE could be defined for 52.3% of the 432 isolates, with NAP2 (n=122) being the most common. Ninety-one per cent (71/78) of NAP2 isolates were recovered from patients with hospital-acquired C. difficile disease. Other NAP types and isolates with non-NAP-type PFGE patterns were less frequently associated with hospital-acquired disease. Community-acquired disease (35.3% of isolates) was associated with a wide variety of NAP types. NAP2 isolates were homogeneous (85.5% had SmaI PFGE pattern 0003) and demonstrated low susceptibility to moxifloxacin (6.6%) and clindamycin (1.6%) compared with non-NAP2 isolates (64.1-93.2% moxifloxacin susceptible; 14.1-28.2% clindamycin susceptible). All isolates of C. difficile in Manitoba were susceptible to metronidazole, piperacillin-tazobactam, amoxicillin-clavulanate and meropenem. NAP2 isolates of toxigenic C. difficile were approximately three times more common than NAP1 isolates (28.2 vs 9.1%) in Manitoba in 2006-2007, and these isolates demonstrated high levels of clonality and multidrug resistance, and were associated with hospital acquisition.

The responses of Aboriginal Canadians to adjuvanted pandemic (H1N1) 2009 influenza vaccine.

BACKGROUND: Because many Aboriginal Canadians had severe cases of pandemic (H1N1) 2009 influenza, they were given priority access to vaccine. However, it was not known if the single recommended dose would adequately protect people at high risk, prompting our study to assess responses to the vaccine among Aboriginal Canadians. METHODS: We enrolled First Nations and Métis adults aged 20-59 years in our prospective cohort study. Participants were given one 0.5-mL dose of ASO3-adjuvanted pandemic (H1N1) 2009 vaccine (Arepanrix, GlaxoSmithKline Canada). Blood samples were taken at baseline and 21-28 days after vaccination. Paired sera were tested for hemagglutination-inhibiting antibodies at a reference laboratory. To assess vaccine safety, we monitored the injection site symptoms of each participant for seven days. We also monitored patients for general symptoms within 7 days of vaccination and any use of the health care system for 21-28 days after vaccination. RESULTS: We enrolled 138 participants in the study (95 First Nations, 43 Métis), 137 of whom provided all safety data and 136 of whom provided both blood samples. First Nations and Métis participants had similar characteristics, including high rates of chronic health conditions (74.4%-76.8%). Pre-existing antibody to the virus was detected in 34.3% of the participants, all of whom boosted strongly with vaccination (seroprotection rate [titre ≥ 40] 100%, geometric mean titre 531-667). Participants with no pre-existing antibody also responded well. Fifty-eight of 59 (98.3%) First Nations participants showed seroprotection and a geometric mean titre of 353.6; all 30 Métis participants with no pre-existing antibody showed seroprotection and a geometric mean titre of 376.2. Pain at the injection site and general symptoms frequently occurred but were short-lived and generally not severe, although three participants (2.2%) sought medical attention for general symptoms. INTERPRETATION: First Nations and Métis adults responded robustly to ASO3-adjuvanted pandemic (H1N1) 2009 vaccine. Virtually all participants showed protective titres, including those with chronic health conditions.

Population-based surveillance of Clostridium difficile infection in Manitoba, Canada, by using interim surveillance definitions.

OBJECTIVE: To apply interim surveillance definitions of Clostridium difficile infection (CDI) cases to 1 year of data from the provincewide surveillance system of Manitoba, Canada, to determine the epidemiology of CDI incident cases in a population. METHODS: CDI cases were categorized with interim surveillance definitions developed by an ad hoc C. difficile surveillance working group. Incident cases recorded in the provincial CDI database between July 2005 and June 2006 were linked to the provincial hospitalization and nursing home databases and analyzed. RESULTS: One thousand six incident cases were identified over 1 year. Five hundred fifteen (51%) cases were associated with and began in a healthcare facility (HCF), whereas 275 (27%) were associated with and began in the community. An additional 131 (13%) cases were HCF associated but began in the community, while 85 (8%) were of indeterminate origin. Cases of HCF-associated CDI occurred in patients who were older than did cases of community-associated CDI (P < .0001). The provincial rate of community-onset cases was 23.4 per 100,000 person-years, and rates varied among geographic areas. HCF-associated CDI rates among the 10 largest hospitals varied from 0.5 to 8.4 per 10,000 patient-days. The time to CDI onset after hospital admission indicated that 25% of nosocomial cases began by the 8th day, and 50% began by the 17th day. CONCLUSIONS: Although the majority of CDI cases were associated with exposure to a HCF, 40% of incident CDI began in the community. Populations with HCF- and community-associated CDI demonstrated significantly different age distributions. The wide variation of rates among HCFs requires explanation. The high percentage of incident cases in the community warrants increased study.