Paul Van Caeseele

University of Manitoba, Winnipeg, Manitoba, Canada

Are you Paul Van Caeseele?

Claim your profile

Publications (35)155.74 Total impact

  • John L Wylie, Paul Van Caeseele
    [Show abstract] [Hide abstract]
    ABSTRACT: Increases in case numbers for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) have been noted on a global level. This study analysed 13 years of testing data to better understand case detection trends over time. Data consisted of all nucleic acid probe and nucleic acid amplification diagnostic testing for CT and NG for the population of Manitoba, Canada (1.2 million); January 2000 to December 2012. Logistic regression models were used to analyse ORs associated with positive CT and NG tests by year. Included in the model as predictor variables were test type, specimen type, patient age and residence location. For both male and female CT results, unadjusted OR by year mimicked absolute case counts, reflecting a general increase over time in case counts. Adjustment for laboratory-related variables altered this relationship such that a general decline in the odds of identifying a CT case over time was evident. For both male and female NG results, adjustment for laboratory and demographic variables altered the OR associated with each year, but to a lesser extent than for CT. Temporal trends associated with CT case numbers should be interpreted after controlling, at a minimum, for the influence of laboratory-related variables. Interpretation of NG trends is feasible using only the number of reported NG cases. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
    Sexually transmitted infections 05/2015; DOI:10.1136/sextrans-2014-051702 · 3.08 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background. Canada's Sentinel Physician Surveillance Network (SPSN) links genetic, antigenic and vaccine effectiveness (VE) measures in an integrated platform of influenza monitoring, described here for the 2013-14 season of resurgent A(H1N1)pdm09 and late-season influenza B activity. Methods. VE was estimated as [1-OddsRatio]x100% comparing vaccination status between influenza test-positive cases and test-negative controls. Vaccine-virus relatedness was assessed by genomic sequence analysis and hemagglutination-inhibition assay. Results. Analyses included 1037 controls (33%vaccinated) and 663 cases (15%vaccinated): 415 A(H1N1)pdm09, 15 A(H3N2), 191 B/Yamagata-lineage, 6 B/Victoria-lineage, 36 unknown subtype/lineage. A(H1N1)pdm09 viruses belonged to clade-6B, distinguished by a K163Q substitution, but remained antigenically-similar to A/California/07/2009-like vaccine with adjusted-VE of 71%(95%CI=58-80%). Most (83%) B/Yamagata-lineage viruses clustered phylogenetically with the prior 2012-13 season's B/Wisconsin/01/2010-like clade-3 vaccine-strain while only 17% clustered with the current 2013-14 season's B/Massachusetts/02/2012-like clade-2 vaccine-strain. B/Yamagata-lineage adjusted-VE was 73%(95%CI=56-83%), lower with partial calendar-time adjustment for clade-mismatched B/Wisconsin/01/2010-like (VE=63%;95%CI=41-77%) versus clade-matched B/Massachusetts/02/2012-like (VE=88%;95%CI=48-97%) viruses. No H3N2 viruses clustered with the A/Texas/50/2012-like clade-3C.1 vaccine-strain, and more than half were antigenically-mismatched but sparse data did not support VE. Conclusions. VE corresponded with antigenically-conserved A(H1N1)pdm09 and lineage-matched B/Yamagata viruses with clade-level variation. Surveillance linking genotypic, phenotypic and epidemiologic measures of vaccine-virus relatedness and effectiveness could better inform predictions of vaccine performance and reformulation.
    The Journal of Infectious Diseases 03/2015; DOI:10.1093/infdis/jiv177 · 5.78 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background Despite the public health significance of annual influenza outbreaks, the literature comparing the epidemiology of influenza A and B infections is limited and dated and may not reflect recent trends. In Canada, the relative contribution of influenza A and B to the burden of morbidity is not well understood. We examined rates of laboratory-confirmed cases of influenza A and B (LCI-A and LCI-B) in the Canadian province of Manitoba between 1993 and 2008 and compared cases of the two types in terms of socio-demographic and clinical characteristics.Methods Laboratory-confirmed cases of influenza A and B in Manitoba between 1993 and 2008 were identified from the Cadham Provincial Laboratory (CPL) Database and linked to de-identified provincial administrative health records. Crude and age-adjusted incidence rates of LCI-A and LCI-B were calculated. Demographic characteristics, health status, health service use, and vaccination history were compared by influenza type.ResultsOver the study period, 1,404 of LCI-A and 445 cases of LCI-B were diagnosed, corresponding to an annual age-standardized rate of 7.2 (95% CI: 6.5-7.9) for LCI-A and 2.2 (CI: 1.5 ¿ 3.0) per 100,000 person-years for LCI-B. Annual rates fluctuated widely but there was less variation in the LCI-B rates. For LCI-A, but not LCI-B, incidence was inversely related to household income. Older age, urban residence and past hospitalization were associated with increased detection of LCI-A whereas receipt of the influenza vaccine was associated with decreased LCI-A detection. Once socio-demographic variables were controlled, having a pre-existing chronic disease or immune suppression was not related to influenza type.Conclusion Influenza A and B affected different segments of the population. Older age was associated with increased LCI-A detection, but not pre-existing chronic diseases. This information may be useful to public health professionals in planning and evaluating new and existing seasonal influenza vaccines.
    BMC Public Health 01/2015; 15(1):35. DOI:10.1186/s12889-015-1351-z · 2.32 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A child with a complicated medical history that included asplenia acquired an infection with Babesia microti in the summer of 2013 and had not travelled outside of Manitoba. Although the clinical findings were subtle, astute laboratory work helped to reach a preliminary identification of Babesia species, while reference laboratory testing confirmed the diagnosis. Blacklegged ticks (Ixodes scapularis) are known to transmit Borrelia burgdorferi and Anaplasma phagocytophilum in the province; however, the present case represents the first known instance of tick-borne B microti, both in Manitoba and in Canada. The expanding territory of the blacklegged tick increases the relevance of this emerging infection. Clinicians, laboratory medical practitioners and public health officials should be aware of B microti as a potential locally acquired infection in Canada.
    The Canadian journal of infectious diseases & medical microbiology = Journal canadien des maladies infectieuses et de la microbiologie medicale / AMMI Canada 11/2014; 25(6):e87-9. · 0.49 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background. In 2010, Winnipeg, Canada, experienced a doubling of invasive pneumococcal disease (IPD) rates, with a significant increase in the number of cases due to Streptococcus pneumoniae serotype 12F, which previously had accounted for very few cases each year. Methods. All serotype 12F IPD cases reported between September 2009 and January 2011 were reviewed. Pulsed-field gel electrophoresis (PFGE) and multilocus variable number tandem repeat analysis (MLVA) were conducted on all isolates. PFGE and MLVA patterns identified several possible clusters. Additional interviews were conducted to obtain information on risk factors and outcomes. Results. Between September 2009 and January 2011, 169 cases of IPD were identified. The number of IPD cases due to 12F serotype increased sharply from about 3-4 cases per year (6% of IPD cases) in 2007-2009 to 28 (29%) in 2010. All 12F isolates belonged to a single sequence type (ST218), and they were generally susceptible to penicillin and fluoroquinolones but not to erythromycin. Compared with cases caused by other serotypes, patients with serotype 12F were more likely to be homeless, reside in low-income inner-city communities, and engage in substance abuse, including intravenous and crack cocaine use. Subclusters identified using MLVA had even higher rates of homelessness and substance use. Conclusions. An immunization campaign targeting high-risk groups was undertaken with pneumococcal polysaccharide vaccine, and subsequently rates of serotype 12F decreased. To our knowledge, this is the largest documented community outbreak of serotype 12F IPD and the first report of an outbreak of IPD serotype 12F in a marginalized urban population in Canada.
    Clinical Infectious Diseases 05/2014; 59(5). DOI:10.1093/cid/ciu366 · 9.42 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Influenza vaccine effectiveness (VE) is generally interpreted in the context of vaccine match/mismatch to circulating strains with evolutionary drift in the latter invoked to explain reduced protection. During the 2012-13 season, however, detailed genotypic and phenotypic characterization shows that low VE was instead related to mutations in the egg-adapted H3N2 vaccine strain rather than antigenic drift in circulating viruses. Component-specific VE against medically-attended, PCR-confirmed influenza was estimated in Canada by test-negative case-control design. Influenza A viruses were characterized genotypically by amino acid (AA) sequencing of established haemagglutinin (HA) antigenic sites and phenotypically through haemagglutination inhibition (HI) assay. H3N2 viruses were characterized in relation to the WHO-recommended, cell-passaged vaccine prototype (A/Victoria/361/2011) as well as the egg-adapted strain as per actually used in vaccine production. Among the total of 1501 participants, influenza virus was detected in 652 (43%). Nearly two-thirds of viruses typed/subtyped were A(H3N2) (394/626; 63%); the remainder were A(H1N1)pdm09 (79/626; 13%), B/Yamagata (98/626; 16%) or B/Victoria (54/626; 9%). Suboptimal VE of 50% (95%CI: 33-63%) overall was driven by predominant H3N2 activity for which VE was 41% (95%CI: 17-59%). All H3N2 field isolates were HI-characterized as well-matched to the WHO-recommended A/Victoria/361/2011 prototype whereas all but one were antigenically distinct from the egg-adapted strain as per actually used in vaccine production. The egg-adapted strain was itself antigenically distinct from the WHO-recommended prototype, and bore three AA mutations at antigenic sites B [H156Q, G186V] and D [S219Y]. Conversely, circulating viruses were identical to the WHO-recommended prototype at these positions with other genetic variation that did not affect antigenicity. VE was 59% (95%CI:16-80%) against A(H1N1)pdm09, 67% (95%CI: 30-85%) against B/Yamagata (vaccine-lineage) and 75% (95%CI: 29-91%) against B/Victoria (non-vaccine-lineage) viruses. These findings underscore the need to monitor vaccine viruses as well as circulating strains to explain vaccine performance. Evolutionary drift in circulating viruses cannot be regulated, but influential mutations introduced as part of egg-based vaccine production may be amenable to improvements.
    PLoS ONE 03/2014; 9(3):e92153. DOI:10.1371/journal.pone.0092153 · 3.53 Impact Factor
  • Eurosurveillance: bulletin europeen sur les maladies transmissibles = European communicable disease bulletin 02/2014; 19(5). DOI:10.2807/1560-7917.ES2014.19.5.20690 · 4.66 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background. We estimate vaccine effectiveness (VE) against both influenza A/subtypes and B/lineages in Canada for the 2011-12 trivalent inactivated influenza vaccine (TIV) with components entirely unchanged from 2010-11 and in the context of phenotypic and genotypic characterization of circulating viruses.Methods. In a test-negative case-control study VE was estimated as [1-adjustedOddsRatio]X100 for RT-PCR-confirmed influenza in vaccinated versus non-vaccinated participants. Viruses were characterized by hemagglutination-inhibition (HI) and sequencing of antigenic sites of the hemagglutinin (HA) gene.Results. There were 1507 participants. VE against A(H1N1)pdm09 was 80%(95%CI:52-92%): circulating viruses were HI-characterized as vaccine-matched and bore just 2 amino-acid (AA) differences from vaccine. VE against A/H3N2 was 51%(95%CI:10-73%): circulating viruses were HI-characterized as vaccine-related but bore ≥11AA differences from vaccine. VE against influenza/B was 51%(95%CI:26-67%): 71%(95%CI:40-86%) for lineage-matched B/Victoria and 27%(95%CI-21-56%) for lineage-mismatched B/Yamagata. For both influenza A and B types, VE was similar among recipients of either 2010-11 or 2011-12 TIV alone, higher when vaccinated both seasons.Conclusions. Phenotypic and genotypic characterization of circulating and vaccine viruses enhances understanding of TIV performance, shown in 2011-12 to be substantial against well-conserved A(H1N1)pdm09 and lineage-matched influenza/B, suboptimal against genetic-variants of A/H3N2 and further reduced against lineage-mismatched influenza/B. With unchanged vaccine components, protection may extend beyond a single season.
    The Journal of Infectious Diseases 01/2014; DOI:10.1093/infdis/jiu048 · 5.78 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The monitoring of antimicrobial susceptibilities in Neisseria gonorrhoeae isolates and characterization of N. gonorrhoeae multiantigen sequence types (NG-MAST, ST) provide important surveillance data as resistance rates continue to rise. A total of 2970 N. gonorrhoeae isolates were collected by Canadian provincial public health laboratories in 2010, and 1233 were submitted to the National Microbiology Laboratory for testing. The NG-MAST and minimum inhibitory concentration (MIC) by agar dilution were determined for each isolate. Of the 2970 isolates, 25.1% were resistant to penicillin, 34.6% resistant to tetracycline, 31.5% resistant to erythromycin, 35.9% resistant to ciprofloxacin, and 1.2% resistant to azithromycin. Decreased susceptibility to cefixime (MIC ≥ 0.25 mg/L) and ceftriaxone (MIC ≥ 0.125 mg/L) was identified in 3.2% and 7.3% of the isolates, respectively. The most common STs found in Canada were ST1407 (13.3%), ST3150 (11.3%), and ST3158 (9.0%), with 249 different STs identified among the isolates. Within the ST1407 group, 19.5% and 43.3% isolates have decreased susceptibility to cefixime and ceftriaxone, respectively. ST1407, the most prevalent NG-MAST in Canada in 2010, has been associated with high-level ceftriaxone MICs and with cefixime treatment failure cases worldwide. Identification and monitoring of STs and corresponding antimicrobial resistance profiles may be useful in surveillance programs and be used to inform public health actions.
    Canadian Journal of Microbiology 10/2013; 59(10):671-678. DOI:10.1139/cjm-2013-0357 · 1.18 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: It is rapidly becoming apparent that many E. coli pathotypes cause a considerable burden of human disease. Surveillance of these organisms is difficult because there are few or no simple, rapid methods for detecting and differentiating the different pathotypes. MALDI-TOF mass spectroscopy has recently been rapidly and enthusiastically adopted by many clinical laboratories as a diagnostic method because of its high throughput, relatively low cost, and adaptability to the laboratory workflow. To determine whether the method could be adapted for E. coli pathotype differentiation the Bruker Biotyper methodology and a second methodology adapted from the scientific literature were tested on isolates representing eight distinct pathotypes and two other groups of E. coli. A total of 136 isolates was used for this study. Results confirmed that the Bruker Biotyper methodology that included extraction of proteins from bacterial cells was capable of identifying E. coli isolates from all pathotypes to the species level and, furthermore, that the Bruker extraction and MALDI-TOF MS with the evaluation criteria developed in this work was effective for differentiating most pathotypes.
    Journal of microbiological methods 06/2013; 94(3). DOI:10.1016/j.mimet.2013.06.020 · 2.10 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The 2012/13 influenza season in Canada has been characterised to date by early and moderately severe activity, dominated (90%) by the A(H3N2) subtype. Vaccine effectiveness (VE) was assessed in January 2013 by Canada’s sentinel surveillance network using a test-negative case–control design. Interim adjusted- VE against medically attended laboratory-confirmed influenza A(H3N2) infection was 45% (95% CI: 13–66). Influenza A(H3N2) viruses in Canada are similar to the vaccine, based on haemagglutination inhibition; however, antigenic site mutations are described in the haemagglutinin gene.
    Eurosurveillance: bulletin europeen sur les maladies transmissibles = European communicable disease bulletin 01/2013; 18(5). · 4.66 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The laboratory system in Manitoba for routine cervical screening is outdated and costly. We developed a costing framework for the implementation of new cervical cancer screening technology models. The direct healthcare costs in the baseline model, the conventional Papanicolaou smear test, were compared with estimates of two newer technology platforms, liquid-based cytology and human papillomavirus (HPV) testing. The findings revealed that HPV testing as a primary screening model for women aged 30 years and older represented the least-cost strategy. Liquid-based cytology would be used for routine screening of women under 30 years of age and to triage women 30 years and older whose results were HPV positive.
    Healthcare quarterly (Toronto, Ont.) 01/2013; 16(1):77-85.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Please cite this paper as: Kim et al. (2012) Characteristics of respiratory viral infections during influenza season in Canadian Hutterite Communities. Influenza and Other Respiratory Viruses DOI:10.1111/irv.12021. Objectives:  To determined the pathogen-specific incidence of respiratory virus infection in Hutterite communities occurring over the 2008-2009 influenza season and assess temporal characteristics of respiratory illness related to infection. Methods:  3273 participants community members enrolled in a cluster randomized trial of influenza vaccine were studied. Results:  One hundred forty-nine participants had laboratory-confirmed influenza, and 595 had at least one episode of laboratory-confirmed respiratory viral infection other than influenza. Entero/rhinovirus had the highest incidence among children <5 years. Conclusions:  A decline in the incidence of infections with age was observed for influenza as well as for most other respiratory viruses.
    Influenza and Other Respiratory Viruses 10/2012; 7(6). DOI:10.1111/irv.12021 · 1.90 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We conducted a multicenter trial in Canada to assess the value of using trueness controls (TC) for rubella virus IgG and hepatitis B virus surface antibody (anti-HBs) serology to determine test performance across laboratories over time. TC were obtained from a single source with known international units. Seven laboratories using different test systems and kit lots included the TC in routine assay runs of the analytes. TC measurements of 1,095 rubella virus IgG and 1,195 anti-HBs runs were plotted on Levey-Jennings control charts for individual laboratories and analyzed using a multirule quality control (MQC) scheme as well as a single three-standard-deviation (3-SD) rule. All rubella virus IgG TC results were "in control" in only one of the seven laboratories. Among the rest, "out-of-control" results ranged from 5.6% to 10% with an outlier at 20.3% by MQC and from 1.1% to 5.6% with an outlier at 13.4% by the 3-SD rule. All anti-HBs TC results were "in control" in only two laboratories. Among the rest, "out-of-control" results ranged from 3.3% to 7.9% with an outlier at 19.8% by MQC and from 0% to 3.3% with an outlier at 10.5% by the 3-SD rule. In conclusion, through the continuous monitoring of assay performance using TC and quality control rules, our trial detected significant intra- and interlaboratory, test system, and kit lot variations for both analytes. In most cases the assay rejections could be attributable to the laboratories rather than to kit lots. This has implications for routine diagnostic screening and clinical practice guidelines and underscores the value of using an approach as described above for continuous quality improvement in result reporting and harmonization for these analytes.
    Clinical and vaccine Immunology: CVI 08/2012; 19(10):1624-32. DOI:10.1128/CVI.00294-12 · 2.37 Impact Factor
  • Source
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: 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.
    Emerging Infectious Diseases 05/2012; 18(5):801-10. DOI:10.3201/eid1805.111596 · 7.33 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In Canada before 2005, large outbreaks of pneumococcal disease, including invasive pneumococcal disease caused by serotype 5, were rare. Since then, an epidemic of serotype 5 invasive pneumococcal disease was reported: 52 cases during 2005, 393 during 2006, 457 during 2007, 104 during 2008, and 42 during in 2009. Of these 1,048 cases, 1,043 (99.5%) occurred in the western provinces of Canada. Median patient age was 41 years, and most (659 [59.3%]) patients were male. Most frequently representing serotype 5 cases (compared with a subset of persons with non-serotype 5 cases) were persons who were of First Nations heritage or homeless. Restriction fragment-length polymorphism typing indicated that the epidemic was caused by a single clone, which multilocus sequence typing identified as sequence type 289. Large pneumococcal epidemics might go unrecognized without surveillance programs to document fluctuations in serotype prevalence.
    Emerging Infectious Diseases 05/2012; 18(5):733-40. DOI:10.3201/eid1805.110235 · 7.33 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Most pediatric adenovirus respiratory infections are mild and indistinguishable from other viral causes. However, in a few children, the disease can be severe and result in substantial morbidity. We describe the epidemiologic, clinical, radiologic features and outcome of adenovirus lower respiratory tract infections (LRTI) in Aboriginal and Non-Aboriginal children in Manitoba, Canada during the years 1991 and 2005. This was a retrospective study of 193 children who presented to the department of pediatrics at Winnipeg Children's Hospital, Manitoba, Canada with LRTI and had a positive respiratory culture for adenovirus. Patients' demographics, clinical and radiologic features and outcomes were collected. Adenovirus serotype distributions and temporal associations were described. Approximate incidence comparisons (detection rates) of adenovirus LRTI among Aboriginal and Non-Aboriginal children were estimated with 95% confidence intervals. Adenovirus infections occurred throughout the year with clusters in the fall and winter. Serotypes 1 to 3 were the predominant isolates (two thirds of the cases). The infection was more frequent among Canadian Aboriginals, as illustrated in 2004, where its incidence in children 0-4 years old was 5.6 fold higher in Aboriginals (13.51 vs. 2.39 per 10,000, p < 0.000). There were no significant differences in length of hospitalization and use of ventilator assistance between the two groups (p > 0.185 and p > 0.624, respectively) nor across serotypes (p > 0.10 and p > 0.05, respectively). The disease primarily affected infants (median age, 9.5 months). Most children presented with bronchiolitis or pneumonia, with multi-lobar consolidations on the chest x-ray. Chronic (residual) changes were documented in 16 patients, with eight patients showing bronchiectasis on the chest computerized tomography scan. Adenovirus infection is associated with significant respiratory morbidities, especially in young infants. The infection appears to be more frequent in Aboriginal children. These results justify a careful follow-up for children with adenovirus LRTI.
    BMC Infectious Diseases 03/2012; 12:55. DOI:10.1186/1471-2334-12-55 · 2.56 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Little is known about the determinants of pandemic H1N1 (pH1N1) infection in Canada among low-income, inner city populations. To inform future influenza planning, the seroprevalence of pH1N1 antibodies among inner city clinic attendees in Winnipeg (Manitoba) according to sociodemographic and risk factor characteristics were estimated and vaccination rates were explored. Adults presenting to three inner city community clinics in Winnipeg from October 2009 to December 2009 were recruited as study participants (n=458). A questionnaire was administered to collect demographic, risk factor and symptom information, and a venous blood sample was collected for hemagglutination inhibition assay testing to detect the presence of antibodies against pH1N1. Approximately one-half (53%) of the study participants reported an annual household income of <$10,000/year, and 65% identified as Aboriginal. pH1N1 positivity was 5.7% among those enrolled early in the study and 15.5% among those enrolled later in the study. Positivity was higher among participants who were female, Aboriginal and in contact with children ≤5 years of age. The overall pH1N1 vaccination rate was 28%. pH1N1 positivity was high among low-income adults accessing clinics in Winnipeg's inner city compared with the general population. Of further concern were the low rates of uptake of both seasonal and pH1N1 influenza vaccinations. When planning for future influenza outbreaks, it is important to incorporate strategies for the prevention, control, and care of influenza among low-income and inner city adults.
    The Canadian journal of infectious diseases & medical microbiology = Journal canadien des maladies infectieuses et de la microbiologie medicale / AMMI Canada 01/2012; 23(2):65-70. · 0.49 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: 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. 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. 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. 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.
    Vaccine 08/2011; 29(45):7975-81. DOI:10.1016/j.vaccine.2011.08.068 · 3.49 Impact Factor

Publication Stats

616 Citations
155.74 Total Impact Points

Institutions

  • 2002–2015
    • University of Manitoba
      • Department of Biochemistry and Medical Genetics
      Winnipeg, Manitoba, Canada
  • 2012
    • Government of Manitoba, Canada
      Winnipeg, Manitoba, Canada
  • 2003
    • Health Sciences Centre Winnipeg
      Winnipeg, Manitoba, Canada