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1.  How well do ICD-9 physician claim diagnostic codes identify confirmed pertussis cases in Alberta, Canada? A Canadian Immunization Research Network (CIRN) Study 
Rates of Bordetella pertussis have been increasing in Alberta, Canada despite vaccination programs. Waning immunity from existing acellular component vaccines may be contributing to this. Vaccine effectiveness can be estimated using a variety of data sources including diagnostic codes from physician billing claims, public health records, reportable disease and laboratory databases. We sought to determine if diagnostic codes from billing claims (administrative data) are adequately sensitive and specific to identify pertussis cases among patients who had undergone disease-specific laboratory testing.
Data were extracted for 2004–2014 from a public health communicable disease database that contained data on patients under investigation for B. pertussis (both those who had laboratory tests and those who were epidemiologically linked to laboratory-confirmed cases) in Alberta, Canada. These were deterministically linked using a unique lifetime person identifier to the provincial billing claims database, which contains International Classification of Disease version 9 (ICD-9) diagnostic codes for physician visits. We examined visits within 90 days of laboratory testing. ICD-9 codes 033 (whooping cough), 033.0 (Bordetella pertussis), 033.1 (B. parapertussis), 033.8 (whooping cough, other specified organism), and 033.9 (whooping cough, other unspecified organism) in any of the three diagnostic fields for a claim were classified as being pertussis-specific codes. We calculated sensitivity, specificity, positive (PPV) and negative (NPV) predictive values.
We identified 22,883 unique patients under investigation for B. pertussis. Of these, 22,095 underwent laboratory testing. Among those who had a laboratory test, 2360 tested positive for pertussis. The sensitivity of a pertussis-specific ICD-9 code for identifying a laboratory-confirmed case was 38.6%, specificity was 76.9%, PPV was 16.0%, and NPV was 91.6%.
ICD-9 codes from physician billing claims data have low sensitivity and moderate specificity to identify laboratory-confirmed pertussis among persons tested for pertussis.
Electronic supplementary material
The online version of this article (doi:10.1186/s12913-017-2321-1) contains supplementary material, which is available to authorized users.
PMCID: PMC5508611  PMID: 28701222
Pertussis; Validation studies; International classification of diseases; ICD 9; Sensitivity; Specificity; Health services research
2.  Outbreaks of influenza‐like illness in long‐term care facilities in Winnipeg, Canada 
Please cite this paper as: Mahmud et al. (2012) Outbreaks of influenza‐like illness in long‐term care facilities in Winnipeg, Canada. Influenza and Other Respiratory Viruses 10.1111/irv.12052
Background  Outbreaks of influenza‐like illness (ILI) are common in long‐term care facilities (LTCFs) and result in significant morbidity and mortality among residents.
Objectives  We describe patterns of reported ILI outbreaks in LTCFs in Winnipeg, Canada, and examine LTCF and outbreak characteristics that influence the clinical outcomes of these outbreaks.
Methods  We analyzed the electronic records of all ILI outbreaks reported by LTCFs in Winnipeg from 2003 to 2011. Outbreak duration, ILI attack rates among staff and residents, and residents’ death rates were calculated by presumed viral etiology, staff vaccination rates, type of influenza chemoprophylaxis used, and time to notification to public health.
Results  Of a total of 154 reported outbreaks, most (N = 80) were attributed to influenza, and these outbreaks tended to have higher attack and death rates among LTCF residents compared with outbreaks caused by other respiratory viruses (12) or those of unknown etiology (62). About 92% of residents and 38% of staff of the average LTCFs were vaccinated. Chemoprophylaxis was used in 57·5% of influenza outbreaks. Regardless of presumed viral etiology, outbreaks reported within 3 days of onset ended sooner and had lower attack and mortality rates among residents.
Conclusions  Influenza‐like illness outbreaks still occur among highly immunized LTCF residents, so in addition to vaccination of staff and residents, it is important to maintain competent infection control practices. Early identification and notification to public health authorities and possibly early initiation of control measures could improve clinical outcomes of ILI outbreaks.
PMCID: PMC4634272  PMID: 23145997
Epidemiology; influenza‐like illness outbreaks; long‐term care facilities
3.  No Association between 2008–09 Influenza Vaccine and Influenza A(H1N1)pdm09 Virus Infection, Manitoba, Canada, 2009 
Emerging Infectious Diseases  2012;18(5):801-810.
Receipt of seasonal inactivated trivalent vaccine neither increased nor decreased the risk for pandemic influenza virus infection.
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.
PMCID: PMC3358049  PMID: 22516189
epidemiology; pandemic (H1N1) 2009; pandemic (H1N1) 2009 virus; pandemic A(H1N1)2009 virus; influenza A(H1N1)pdm09; trivalent influenza vaccine; 2008–09 inactivated trivalent influenza vaccine; TIV; case–control study; influenza; Canada; viruses
4.  Protocol of a randomised controlled trial characterising the immune responses induced by varicella-zoster virus (VZV) vaccination in healthy Kenyan women: setting the stage for a potential VZV-based HIV vaccine 
BMJ Open  2017;7(9):e017391.
A protective HIV vaccine would be expected to induce durable effector immune responses at the mucosa, restricting HIV infection at its portal of entry. We hypothesise that use of varicella-zoster virus (VZV) as an HIV delivery vector could generate sustained and robust tissue-based immunity against HIV antigens to provide long-term protection against HIV. Given that HIV uniquely targets immune-activated T cells, the development of human vaccines against HIV must also involve a specific examination of the safety of the vector. Thus, we aim to evaluate the effects of VZV vaccination on the recipients’ immune activation state, and on VZV-specific circulating humoral and cellular responses in addition to those at the cervical and rectal mucosa.
Methods and analysis
This open-label, randomised, longitudinal crossover study includes healthy Kenyan VZV-seropositive women at low risk for HIV infection. Participants receive a single dose of a commercial live-attenuated VZVOka vaccine at either week 0 (n=22) or at week 12 (n=22) of the study and are followed for 48 and 36 weeks postvaccination, respectively. The primary outcome is the change on cervical CD4+ T-cell immune activation measured by the coexpression of CD38 and HLA-DR 12 weeks postvaccination compared with the baseline (prevaccination). Secondary analyses include postvaccination changes in VZV-specific mucosal and systemic humoral and cellular immune responses, changes in cytokine and chemokine measures, study acceptability and feasibility of mucosal sampling and a longitudinal assessment of the bacterial community composition of the mucosa.
Ethics and dissemination
The study has ethical approval from Kenyatta National Hospital/University of Nairobi Ethics and Research Committee, the University of Toronto Research Ethics Board and by Kenyan Pharmacy and Poisons Board. Results will be presented at conferences, disseminated to participants and stakeholders as well as published in peer-reviewed journals.
Trial registration number
NCT02514018. Pre-results.
PMCID: PMC5623463  PMID: 28939581
varicella-zoster virus; HIV vaccine; immune activation; mucosal immunity; herpes zoster; herpesviridae infections; virus diseases
5.  Methods used for immunization coverage assessment in Canada, a Canadian Immunization Research Network (CIRN) study 
Human Vaccines & Immunotherapeutics  2017;13(8):1928-1936.
Accurate and complete immunization data are necessary to assess vaccine coverage, safety and effectiveness. Across Canada, different methods and data sources are used to assess vaccine coverage, but these have not been systematically described. Our primary objective was to examine and describe the methods used to determine immunization coverage in Canada. The secondary objective was to compare routine infant and childhood coverage estimates derived from the Canadian 2013 Childhood National Immunization Coverage Survey (cNICS) with estimates collected from provinces and territories (P/Ts). We collected information from key informants regarding their provincial, territorial or federal methods for assessing immunization coverage. We also collected P/T coverage estimates for select antigens and birth cohorts to determine absolute differences between these and estimates from cNICS. Twenty-six individuals across 16 public health organizations participated between April and August 2015. Coverage surveys are conducted regularly for toddlers in Quebec and in one health authority in British Columbia. Across P/Ts, different methodologies for measuring coverage are used (e.g., valid doses, grace periods). Most P/Ts, except Ontario, measure up-to-date (UTD) coverage and 4 P/Ts also assess on-time coverage. The degree of concordance between P/T and cNICS coverage estimates varied by jurisdiction, antigen and age group. In addition to differences in the data sources and processes used for coverage assessment, there are also differences between Canadian P/Ts in the methods used for calculating immunization coverage. Comparisons between P/T and cNICS estimates leave remaining questions about the proportion of children fully vaccinated in Canada.
PMCID: PMC5557229  PMID: 28708945
Canada; immunization coverage; immunization registries; immunization registers; vaccine-preventable diseases
6.  Cervical human papillomavirus detection is not affected by menstrual phase 
Sexually transmitted infections  2012;89(3):202-206.
In many settings, human papillomavirus (HPV) DNA testing already plays an important role in cervical cancer screening. It is unclear whether hormonal fluctuations associated with menstrual phase or oral contraceptive (OC) use have any effect on HPV detection. We evaluated the effects of OC use and timing of cervical sampling in relation to women’s last menstrual period (LMP) on HPV detection, and viral load in the Brazilian Ludwig-McGill cohort study.
Women in the cohort were followed every 4–6 months, and at each clinic visit they were asked to complete a questionnaire and to provide a cervical sample for HPV testing. Specimens from 6093 patient visits (n = 2209 women) were categorised according to date of LMP into four distinct phases: follicular (days 5–9), midcycle (days 10–15), luteal (days 16–22), or late luteal (days 23–31).
Compared with follicular phase (referent group), HPV detection did not differ according to reported LMP for midcycle (OR = 1.14, 95% CI 0.95 to 1.37), luteal (OR = 1.03, 95% CI 0.85 to 1.25), or late luteal menstrual phase (OR=1.01, 95% CI 0.83 to 1.24), and was also not influenced by OC use. Analyses restricted to high-risk HPV types (grouped) and HPVs 16 and 18 (separately), produced similar non-significant associations. For HPV-positive samples, we found that the menstrual phase did not influence the total viral load.
These results indicate HPV detection is not associated with menstrual phase. Our findings suggest that standardising the timing of specimen collection for HPV testing is not necessary.
PMCID: PMC5505564  PMID: 23112338
7.  Time and spatial trends in lymphoid leukemia and lymphoma incidence and survival among children and adolescents in Manitoba, Canada: 1984-2013 
PLoS ONE  2017;12(4):e0175701.
To test for time and spatial trends in lymphoid malignancies, including lymphoid leukemia (LL), Hodgkin lymphoma (HL), and non-Hodgkin lymphoma (NHL), in children and adolescents in the province of Manitoba, Canada.
Incident cases diagnosed between 1984 and 2013 were identified from the Manitoba Cancer Registry. We assessed time trends in age-standardized incidence rates using joinpoint regression and in 5-year relative survival using Poisson regression model. Kulldorff's scan method was used to assess spatial variation and clustering.
Age-standardized incidence rates (per million person-years) in males and females were 34.0 (95% confidence interval [CI] 28.9–39.1) and 26.2 (95% CI 21.5–30.7) for LL, 10.5 (95% CI 7.7–13.3) and 12.5 (95% CI 9.4–15.7) for HL, 12.5 (95% CI 9.3–15.4) and 7.7 (95% CI 5.2–10.2) for NHL (except for Burkitt lymphomas), and 3.2 (95% CI 1.6–4.7) and 1.5 (95% CI 0.4–2.5) for Burkitt lymphomas. Age- and sex- standardized LL incidence rate increased 1.4% (95% CI 0.3%-2.5%) per year, while the changes for HL and NHL incidence rates were not statistically significant. There were geographic differences in age-standardized incidence rates for LL, HL, and NHL and spatial clusters were detected in southern part of the province. Five-year relative survival has improved over time and there was no difference between rural and urban areas.
Lymphoid leukemia incidence rate increased over time and varied by geographic area. Further research should examine the factors contributing to these trends.
PMCID: PMC5400229  PMID: 28430788
8.  Canadian Society of Allergy and Clinical Immunology annual scientific meeting 2016 
Alsayegh, Mohammad A. | Alshamali, Hanan | Khadada, Mousa | Ciccolini, Amanda | Ellis, Anne K. | Quint, Diana | Powley, William | Lee, Laurie | Fiteih, Yahya | Baksh, Shairaz | Vliagoftis, Harissios | Gerega, Sebastien K. | Millson, Brad | Charland, Katia | Barakat, Stephane | Sun, Xichun | Jimenez, Ricardo | Waserman, Susan | FitzGerald, Mark J. | Hébert, Jacques | Cognet-Sicé, Josiane | Renahan, Kevin E. | Huq, Saiful | Chooniedass, Rishma | Sawyer, Scott | Pasterkamp, Hans | Becker, Allan | Smith, Steven G. | Zhang, Shiyuan | Jayasundara, Kavisha | Tacon, Claire | Simidchiev, Alex | Nadeau, Gilbert | Gunsoy, Necdet | Mullerova, Hana | Albers, Frank | Kim, Young Woong | Shannon, Casey P. | Singh, Amrit | Neighbour, Helen | Larché, Mark | Tebbutt, Scott J. | Klopp, Annika | Vehling, Lorena | Becker, Allan B. | Subbarao, Padmaja | Mandhane, Piushkumar J. | Turvey, Stuart E. | Sears, Malcolm R. | Azad, Meghan B. | Loewen, Keely | Monchka, Barret | Mahmud, Salaheddin M. | Jong, Geert ‘t | Longo, Cristina | Bartlett, Gillian | Ducharme, Francine M. | Schuster, Tibor | MacGibbon, Brenda | Barnett, Tracie | North, Michelle L. | Brook, Jeff | Lee, Elizabeth | Omana, Vanessa | Thiele, Jenny | Steacy, Lisa M. | Evans, Greg | Diamond, Miriam | Sussman, Gordon L. | Amistani, Yann | Abiteboul, Kathy | Tenn, Mark W. | Yang, ChenXi | Carlsten, Christopher | Conway, Edward M. | Mack, Douglas | Othman, Yasmin | Barber, Colin M. | Kalicinsky, Chrystyna | Burke, Andrea E. | Messieh, Mary | Nair, Parameswaran | Che, Chun T. | Douglas, Lindsay | Liem, Joel | Duan, Lucy | Miller, Charlotte | Dupuis, Pascale | Connors, Lori A. | Fein, Michael N. | Shuster, Joseph | Hadi, Hani | Polk, Brooke | Raje, Nikita | Labrosse, Roxane | Bégin, Philippe | Paradis, Louis | Roches, Anne Des | Lacombe-Barrios, Jonathan | Mishra, Sanju | Lacuesta, Gina | Chiasson, Meredith | Haroon, Babar | Robertson, Kara | Issekutz, Thomas | Leddin, Desmond | Couban, Stephen | Connors, Lori | Roos, Adrienne | Kanani, Amin | Chan, Edmond S. | Schellenberg, Robert | Rosenfield, Lana | Cvetkovic, Anna | Woodward, Kevin | Quirt, Jaclyn | Watson, Wade T. A. | Castilho, Edson | Sullivan, Jennifer A. | Temple, Beverley | Martin, Donna | Cook, Victoria E. | Mills, Christopher | Portales-Casamar, Elodie | Fu, Lisa W. | Ho, Alexander | Zaltzman, Jeffrey | Chen, Lucy | Vadas, Peter | Gabrielli, Sofianne | Clarke, Ann | Eisman, Harley | Morris, Judy | Joseph, Lawrence | LaVieille, Sebastien | Ben-Shoshan, Moshe | Graham, François | Barnes, Charles | Portnoy, Jay | Stagg, Vincent | Simons, Elinor | Lefebvre, Diana | Dai, David | Mandhane, Piushkumar | Sears, Malcolm | Tam, Herman | Simons, F. Estelle R. | Alotaibi, Dhaifallah | Dawod, Bassel | Tunis, Matthew C. | Marshall, Jean | Desjardins, Marylin | Béland, Marianne | Lejtenyi, Duncan | Drolet, Jean-Phillipe | Lemire, Martine | Tsoukas, Christos | Noya, Francisco J.D. | Alizadehfar, Reza | McCusker, Christine T. | Mazer, Bruce D. | Maestre-Batlle, Danay | Gunawan, Evelyn | Rider, Christopher F. | Bølling, Anette K. | Pena, Olga M. | Suez, Daniel | Melamed, Isaac | Hussain, Iftikhar | Stein, Mark | Gupta, Sudhir | Paris, Kenneth | Fritsch, Sandor | Bourgeois, Christelle | Leibl, Heinz | McCoy, Barbara | Noel, Martin | Yel, Leman | Scott, Ori | Reid, Brenda | Atkinson, Adelle | Kim, Vy Hong-Diep | Roifman, Chaim M. | Grunebaum, Eyal | AlSelahi, Eiman | Aleman, Fernando | Oberle, Amber | Trus, Mike | Sussman, Gordon | Kanani, Amin S. | Chambenoi, Olivier | Chiva-Razavi, Sima | Grodecki, Savannah | Joshi, Nikhil | Menikefs, Peter | Holt, David | Pun, Teresa | Tworek, Damian | Hanna, Raphael | Heroux, Delia | Rosenberg, Elli | Stiemsma, Leah | Turvey, Stuart | Denburg, Judah | Mill, Christopher | Teoh, Timothy | Zimmer, Preeti | Avinashi, Vishal | Paina, Mihaela | Darwish Hassan, Ahmed A. | Oliveria, John Paul | Olesovsky, Chris | Gauvreau, Gail | Pedder, Linda | Keith, Paul K. | Plunkett, Greg | Bolner, Michelle | Pourshahnazari, Persia | Stark, Donald | Vostretsova, Kateryna | Moses, Andrew | Wakeman, Andrew | Singer, Alexander | Gerstner, Thomas | Abrams, Elissa | Johnson, Sara F. | Woodgate, Roberta L.
PMCID: PMC5390240
9.  Comparative safety of direct oral anticoagulants and warfarin in venous thromboembolism: multicentre, population based, observational study 
The BMJ  2017;359:j4323.
Objective To determine the safety of direct oral anticoagulant (DOAC) use compared with warfarin use for the treatment of venous thromboembolism.
Design Retrospective matched cohort study conducted between 1 January 2009 and 31 March 2016.
Setting Community based, using healthcare data from six jurisdictions in Canada and the United States.
Participants 59 525 adults (12 489 DOAC users; 47 036 warfarin users) with a new diagnosis of venous thromboembolism and a prescription for a DOAC or warfarin within 30 days of diagnosis.
Main outcome measures Outcomes included hospital admission or emergency department visit for major bleeding and all cause mortality within 90 days after starting treatment. Propensity score matching and shared frailty models were used to estimate adjusted hazard ratios of the outcomes comparing DOACs with warfarin. Analyses were conducted independently at each site, with meta-analytical methods used to estimate pooled hazard ratios across sites.
Results Of the 59 525 participants, 1967 (3.3%) had a major bleed and 1029 (1.7%) died over a mean follow-up of 85.2 days. The risk of major bleeding was similar for DOAC compared with warfarin use (pooled hazard ratio 0.92, 95% confidence interval 0.82 to 1.03), with the overall direction of the association favouring DOAC use. No difference was found in the risk of death (pooled hazard ratio 0.99, 0.84 to 1.16) for DOACs compared with warfarin use. There was no evidence of heterogeneity across centres, between patients with and without chronic kidney disease, across age groups, or between male and female patients.
Conclusions In this analysis of adults with incident venous thromboembolism, treatment with DOACs, compared with warfarin, was not associated with an increased risk of major bleeding or all cause mortality in the first 90 days of treatment.
Trial registration Clinical trials NCT02833987.
PMCID: PMC5641962  PMID: 29042362
10.  Did the H1N1 Vaccine Reduce the Risk of Admission with Influenza and Pneumonia during the Pandemic? 
PLoS ONE  2015;10(11):e0142754.
The extent to which A(H1N1)pdm09 influenza vaccines prevented hospital admissions with pneumonia and influenza (P&I) during the 2009 pandemic remains poorly understood. We evaluated the effectiveness of the A(H1N1)pdm09 and seasonal influenza vaccines (TIV) used during the 2009 mass vaccination campaign in Manitoba (Canada) in preventing P&I hospitalization.
A population-based record-linkage nested case-control study. Cases (N = 1,812) were persons hospitalized with influenza (ICD-10:J09-J11) or pneumonia (ICD-10:J12-J18) during the study period. Age-, gender- and area of residence-matched controls (N = 7,915) were randomly sampled from Manitoba’s Population Registry. Information on receipt of A(H1N1)pdm09 vaccine and TIV was obtained from the Manitoba Immunization Monitoring System, a province-wide vaccine registry.
Overall, the adjuvanted A(H1N1)pdm09 vaccine was 27% (95%CI 13–39%) effective against P&I hospitalization ≥ 14 days following administration. Effectiveness seemed lower among older (≥ 65 years) adults (10%; −16–30%), particularly when compared to under-5 children (58%; 30–75%). The number-needed-to-vaccinate to prevent 1 P&I admission was lowest among <4 year-olds (928) and ≥65 years (1,721). VE against hospitalization with laboratory-confirmed A(H1N1)pdm09 was 70% (39–85%) overall and (91%; 62–98%) ≥ 14 days following vaccination.
Our data suggest that the adjuvanted A(H1N1)pdm09 vaccine was effective in preventing about 55–60% of P&I hospitalizations among children and younger adults who were at much higher risk of infection. Unfortunately, the vaccine was less effective among 65 or older adults. Despite that the vaccine still had a significant population-based impact especially among the very young (<5) and the older (≥ 65 years).
PMCID: PMC4658136  PMID: 26600435
11.  Is obesity associated with advanced stage or grade of colon cancer? 
Canadian Journal of Surgery  2015;58(2):140-142.
Population-based studies from Europe have suggested that obesity is associated with more advanced stage colorectal cancer on presentation. Obesity is an even more prevalent issue in North America, but comparable data on associations with cancer are lacking. We reviewed the cases of 672 patients with colon cancer diagnosed between 2004 and 2008 in the province of Manitoba who underwent surgical resection at a Winnipeg Regional Health Authority–affiliated hospital. We tested if obesity was associated with more advanced cancer stage or grade. On multivariate analysis, after adjusting for age, sex, tumour location and socioeconomic status, we were unable to show any significant associations between body mass index of 30 or more and advanced stage or grade cancer on presentation. The reasons for the lack of association are likely multifactorial, including the pathophysiology of the disease and process factors, such as screening habits and colonoscopic diagnostic success rates in obese patients.
PMCID: PMC4373996  PMID: 25598175
12.  Comparison of the epidemiology of laboratory-confirmed influenza A and influenza B cases in Manitoba, Canada 
BMC Public Health  2015;15:35.
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.
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.
Over 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.
Influenza A and B affected different segments of the population. Older age was associated with increased LCI-A detection, but not with pre-existing chronic diseases. This information may be useful to public health professionals in planning and evaluating new and existing seasonal influenza vaccines.
PMCID: PMC4331145  PMID: 25633280
Epidemiology; Influenza A; Influenza B; Vaccine
13.  Geographical variation and factors associated with colorectal cancer mortality in a universal health care system 
A significant number of deaths attributed to colorectal cancer (CRC) can be prevented if the cancer is detected at an early, curable stage. Although decreasing the incidence of CRC is important, the focus of CRC screening and surveillance has ultimately been to decrease CRC-related mortality. Given that universal health systems are expected to provide equitable access to health care services, reviewing these systems becomes particularly relevant and may help in developing risk-tailored approaches for CRC screening programs. Accordingly, this study examined population-level factors associated with CRC mortality in Manitoba.
To investigate the geographical variation and small geographical area level factors associated with colorectal cancer (CRC) mortality.
Information regarding CRC mortality was obtained from the population-based Manitoba Cancer Registry, population counts were obtained from Manitoba’s universal health care plan Registry and characteristics of the area of residence were obtained from the 2001 Canadian census. Bayesian spatial Poisson mixed models were used to evaluate the geographical variation of CRC mortality and Poisson regression models for determining associations with CRC mortality. Time trends of CRC mortality according to income group were plotted using joinpoint regression.
The southeast (mortality rate ratio [MRR] 1.31 [95% CI 1.12 to 1.54) and southcentral (MRR 1.62 [95% CI 1.35 to 1.92]) regions of Manitoba had higher CRC mortality rates than suburban Winnipeg (Manitoba’s capital city). Between 1985 and 1996, CRC mortality did not vary according to household income; however, between 1997 and 2009, individuals residing in the highest-income areas were less likely to die from CRC (MRR 0.77 [95% CI 0.65 to 0.89]). Divergence in CRC mortality among individuals residing in different income areas increased over time, with rising CRC mortality observed in the lowest income areas and declining CRC mortality observed in the higher income areas.
Individuals residing in lower income neighbourhoods experienced rising CRC mortality despite residing in a jurisdiction with universal health care and should receive increased efforts to reduce CRC mortality. These findings should be of particular interest to the provincial CRC screening programs, which may be able to reduce the disparities in CRC mortality by reducing the disparities in CRC screening participation.
PMCID: PMC4071912  PMID: 24729992
Colorectal cancer mortality; Spatial patterns; Universal health care; Worsening socioeconomic disparities
14.  Low 2012–13 Influenza Vaccine Effectiveness Associated with Mutation in the Egg-Adapted H3N2 Vaccine Strain Not Antigenic Drift in Circulating Viruses 
PLoS ONE  2014;9(3):e92153.
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.
PMCID: PMC3965421  PMID: 24667168
15.  Serological survey of the novel influenza A H1N1 in inner city Winnipeg, Manitoba, 2009 
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.
PMCID: PMC3403663  PMID: 23730311
Epidemiology; Hemagglutination inhibition assay; Inner city; Pandemic Influenza A H1N1; pH1N1; Serological survey
16.  Use of Non-Steroidal Anti-Inflammatory Drugs and Prostate Cancer Risk: A Population-Based Nested Case-Control Study 
PLoS ONE  2011;6(1):e16412.
Despite strong laboratory evidence that non-steroidal anti-inflammatory drugs (NSAIDs) could prevent prostate cancer, epidemiological studies have so far reported conflicting results. Most studies were limited by lack of information on dosage and duration of use of the different classes of NSAIDs.
We conducted a nested case-control study using data from Saskatchewan Prescription Drug Plan (SPDP) and Cancer Registry to examine the effects of dose and duration of use of five classes of NSAIDs on prostate cancer risk. Cases (N = 9,007) were men aged ≥40 years diagnosed with prostatic carcinoma between 1985 and 2000, and were matched to four controls on age and duration of SPDP membership. Detailed histories of exposure to prescription NSAIDs and other drugs were obtained from the SPDP.
Any use of propionates (e.g., ibuprofen, naproxen) was associated with a modest reduction in prostate cancer risk (Odds ratio = 0.90; 95%CI 0.84-0.95), whereas use of other NSAIDs was not. In particular, we did not observe the hypothesized inverse association with aspirin use (1.01; 0.95–1.07). There was no clear evidence of dose-response or duration-response relationships for any of the examined NSAID classes.
Our findings suggest modest benefits of at least some NSAIDs in reducing prostate cancer risk.
PMCID: PMC3030588  PMID: 21297996
17.  Estimated cumulative incidence of pandemic (H1N1) influenza among pregnant women during the first wave of the 2009 pandemic 
Hospitalization and lab confirmed cases of H1N1 have been reported during the first wave of the 2009 pandemic but these are not accurate measures of influenza incidence in the population. We estimated the cumulative incidence of pandemic (H1N1) influenza among pregnant women in the province of Manitoba during the first wave of the 2009 pandemic.
Two panels of stored frozen serum specimens collected for routine prenatal screening were randomly selected for testing before (March 2009, n = 252) and after (August 2009, n = 296) the first wave of the pandemic. A standard hemagglutination inhibition assay was used to detect the presence of IgG antibodies against the pandemic (H1N1) 2009 virus. The cumulative incidence of pandemic (H1N1) influenza was calculated as the difference between the point prevalence rates in the first and second panels.
Of the specimens collected in March, 7.1% were positive for the IgG antibodies (serum antibody titre ≥ 1:40). The corresponding prevalence was 15.7% among the specimens collected in August. The difference indicated a cumulative incidence of 8.6% (95% confidence interval [CI] 3.2%–13.7%). The rate differed geographically, the highest being in the northern regions (20.8%, 95% CI 7.9%–31.8%), as compared with 4.0% (95% CI 0.0%–11.9%) in Winnipeg and 8.9% (95% CI 0.0%–18.8%) in the rest of the province.
We estimated that the cumulative incidence of pandemic (H1N1) influenza among pregnant women in Manitoba during the first wave of the 2009 pandemic was 8.6%. It was 20.8% in the northern regions of the province.
PMCID: PMC2950183  PMID: 20823167
18.  Nutritional Status Of Under-Five Children In Libya; A National Population-Based Survey 
To describe the nutritional status of children under-five years of age in Libya.
Population and methods
A secondary analysis of data of 5348 children taken from a national representative, two-stage, cluster-sample survey that was performed in 1995. Results: Prevalence rates of underweight, wasting, stunting, and overweight were determined using standard definitions in reference to newly established WHO growth charts. The study revealed that 4.3% of children were underweight, 3.7% wasted, 20.7% stunted, and 16.2% overweight. Seventy percent of children had normal weight. Undernutrition was more likely to be found in males, in rural areas, and in underprivileged groups. Overweight was more likely found in urban, privileged groups. Wasting was more common in arid regions; stunting was more common in mountainous regions of Al-Akhdar, Al-Gharbi, and in Sirt. Al-Akhdar had the highest prevalence of overweight.
The country had a low prevalence of underweight and wasting, moderate prevalence of stunting, and high prevalence of overweight. The country is in the early stages of transition with evidence of dual-burden in some regions. Similar surveys are needed to verify secular trends of these nutritional problems, particularly overweight.
PMCID: PMC3074324  PMID: 21499476
Libya; preschool children; nutritional status; underweight; wasting; stunting; overweight
19.  Significant savings in radiologic report turnaround time after implementation of a complete picture archiving and communication system (PACS) 
Journal of Digital Imaging  2000;13(4):175-177.
One of the important advantages of the picture archiving and communication system (PACS) is the time saved in comparison with the conventional system. A group of 100 radiologic studies done in a conventional radiology department is compared with another group of the same number done in a completely filmless PACS department to assess the difference in the radiologist report turnaround time. There was a statistically significant (P<.00001) decrease in the median imaging-to-dictation time (IDT) of the PACS group (3 hours and 40 minutes) in comparison with the pre-PACS group (25 hours and 19 minutes). This can be attributed to the fact that PACS eliminates all the workload associated with hard copy films, thus, improving the department’s efficiency and decreasing the number of lost films.
PMCID: PMC3453071  PMID: 11110256
picture archiving and communication system (PACS); radiology information systems; computer systems

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