No association between 2008-09 influenza vaccine and influenza A(H1N1)pdm09 virus infection, Manitoba, Canada, 2009.

We conducted a population-based study in Manitoba, Canada, to investigate whether use of inactivated trivalent influenza vaccine (TIV) during the 2008-09 influenza season was associated with subsequent infection with influenza A(H1N1)pdm09 virus during the first wave of the 2009 pandemic. Data were obtained from a provincewide population-based immunization registry and laboratory-based influenza surveillance system. The test-negative case-control study included 831 case-patients with confirmed influenza A(H1N1)pdm09 virus infection and 2,479 controls, participants with test results negative for influenza A and B viruses. For the association of TIV receipt with influenza A(H1N1)pdm09 virus infection, the fully adjusted odds ratio was 1.0 (95% CI 0.7-1.4). Among case-patients, receipt of 2008-09 TIV was associated with a statistically nonsignificant 49% reduction in risk for hospitalization. In agreement with study findings outside Canada, our study in Manitoba indicates that the 2008-09 TIV neither increased nor decreased the risk for infection with influenza A(H1N1)pdm09 virus.

Mumps in prison: description of an outbreak in Manitoba, Canada.

OBJECTIVE: There is a lack of published information on the management of mumps in a prison setting. We describe an outbreak of mumps that occurred in a medium-security correctional centre (Milner Ridge) in Manitoba, Canada. METHODS: A case definition of mumps consistent with that in the document "Guidelines for the Prevention and Control of Mumps Outbreaks in Canada" was adopted. Cell culture, polymerase chain reaction, and serology were used for case confirmation. RESULTS: Five confirmed cases of mumps infection were identified at the Milner Ridge Correctional Centre between January 12 and February 5, 2009. One additional confirmed case and 3 additional probable cases were identified at a second correctional centre. Outbreak control at Milner Ridge was accomplished by cohorting the affected units of the centre, providing education on mumps, deferring transfers, and monitoring for further cases. Vaccination was offered to inmates and staff on the assumption, based on average inmate age, that the majority of inmates would have previously received, at most, a single dose of mumps-containing vaccine. CONCLUSION: An outbreak of mumps in a correctional setting was successfully contained via implementation and tailoring of basic infection control measures, and vaccination of inmates and staff. Given the relatively young age of many inmates and the parallels between prisons and dormitories, it could be argued that inmates may represent another group of individuals for whom a second dose of mumps vaccine (if not received in childhood) would be beneficial as primary prophylaxis.

Effectiveness of the pandemic H1N1 influenza vaccines against laboratory-confirmed H1N1 infections: population-based case-control study.

BACKGROUND: Excellent immune responses following 1 or 2 doses of the monovalent inactivated pandemic H1N1 vaccines have been documented, but the effectiveness of these vaccines against laboratory-confirmed H1N1 infections in the general population is not clear. We evaluated the effectiveness of the pandemic H1N1 and seasonal trivalent influenza vaccines (TIV) used during the 2009 mass vaccination campaign in Manitoba (Canada) in preventing laboratory-confirmed H1N1 infections. METHODS: A population-based case-control study using data from Cadham Provincial Laboratory (CPL) and the Manitoba Immunization Monitoring System (MIMS). All Manitoba residents ≥6 months of age who had a respiratory specimen tested at CPL for H1N1 were included in the study. Cases were individuals who tested positive for pandemic H1N1 influenza A by reverse transcriptase-PCR (N=1435). Controls were individuals who tested negative for both influenza A and B (N=2309). Information on receipt of TIV or H1N1 vaccine was obtained by record linkage with MIMS, the population-based province-wide immunization registry. RESULTS: Overall, the adjuvanted H1N1 vaccine was 86% (95%CI 75-93%) effective in preventing laboratory-confirmed H1N1 infections when vaccination occurred ≥14 days before testing. Effectiveness seemed lower among older (≥50 years) individuals [51% (-51 to 84%)] and among those with immunocompromising conditions [67% (-13 to 90%)]. There was also evidence that the H1N1 vaccine might be less effective among those who had received the 2009/10 TIV. DISCUSSION: The adjuvanted H1N1 vaccine used during Manitoba's H1N1 mass vaccination campaign was highly effective against laboratory-confirmed pandemic H1N1 infection, especially among children and younger adults.

The diabetic foot clinic: not a significant source for acquisition of methicillin-resistant Staphylococcus aureus.

BACKGROUND: Diabetic foot clinics have been reported as a source of acquisition of methicillin-resistant Staphylococcus aureus (MRSA). We undertook a 10-year review of patients infected or colonized with MRSA from a tertiary care hospital diabetic foot clinic and describe the epidemiology and genotypes of newly acquired MRSA in comparison with the community at large. METHODS: All new MRSA cases from the diabetic foot clinic, the hospital, and the province were reviewed to identify and compare the 10-year trend in MRSA incidence. Pulsed-field gel electrophoresis using SmaI of all clinic isolates was performed, and standard genotypes were assigned to assess the genetic heterogeneity of MRSA in the clinic. RESULTS: Analysis of trends revealed a low-potential, clinic-attributable incidence and a total clinic incidence that was comparable with regional and hospital MRSA rates. Strains recovered from clinic patients were genetically heterogeneous. CONCLUSION: Our 10-year analysis of trends in MRSA acquisition and MRSA genotypes data does not support significant transmission of MRSA in this clinic setting.