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Cancer patients are among high-risk individuals for whom seasonal influenza vaccine (SIV) is recommended, but rates of vaccination in this subpopulation remain suboptimal; even in jurisdictions with universal influenza vaccination programs. We sought to summarize the evidence to better understand the determinants of SIV uptake (vaccine receipt) among cancer patients. We searched MEDLINE, Embase, and CINAHL from 2000 to February 12, 2020, focusing on articles on the determinants of seasonal influenza vaccination among cancer patients, published in English. Study selection was conducted independently by 2 reviewers. One reviewer extracted data from the included studies and another reviewer checked the extracted data for errors. Outcomes were sociodemographic and health-related factors. We pooled adjusted results from studies using the inverse variance, random-effects method, and reported the odds ratios (OR) and their 95% confidence intervals (CI). Out of 2664 citations, 10 studies (mostly from USA and South Korea) met our eligibility criteria. Overall, being older (OR 2.23, 95% CI 1.46-3.38; I 2 92.3%, [6 studies]), a nonsmoker (1.43, 1.32-1.51; I 2 0%, [4 studies]), having a chronic illness (1.18, 1.07-1.29; I 2 15.7%, [5 studies]), having had a medical check-up in the past year (1.75, 1.65-1.86; I 2 0%, [2 studies]), and having health insurance (1.39, 1.13-1.72; I 2 21.8%, [3 studies]) were associated with increased SIV uptake. Compared with being African-American, being Caucasian was also associated with increased SIV uptake (1.79, 1.47-2.13; I 2 10.7%, [3 studies]). Limited evidence suggests seasonal influenza vaccination among cancer patients may be determined by some sociodemographic and health-related factors., Competing Interests: Conflicts of Interest S.M.M. has received unrestricted research grants from GlaxoSmithKline, Merck, Sanofi Pasteur, Pfizer and Roche-Assurex for unrelated studies, and fees as an advisory board member for Sanofi Pasteur. The other authors declare that they have no conflict of interest., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background/objectives: Despite influenza vaccination programs in various jurisdictions, seasonal influenza vaccine (SIV) uptake remains suboptimal among older people (≥65years old), an important subpopulation for influenza vaccination. We sought to summarize determinants of SIV uptake (any vaccine receipt) and vaccination adherence (receipt of vaccine in two or more seasons in sequence) among older people., Methods: We searched for population-based studies conducted in community-dwelling older people (irrespective of their health status) from 2000-2019. Two reviewers independently selected publications for inclusion. One reviewer extracted data from the included studies; a second checked the extracted data for errors. Disagreements were resolved by discussion and consensus, or a third reviewer. We were interested in the determinants of SIV uptake and vaccination adherence. Where appropriate, we pooled adjusted results using the inverse variance, random-effects method and reported the odds ratios (OR) and their 95% confidence intervals (CI)., Results: Out of 11,570 citations screened, we included 34 cross-sectional studies. The following were associated with increased SIV uptake: being older (OR 1.52, 95%CI 1.38-1.67 [21 studies]), white (1.30, 1.14-1.49 [10 studies]), married (1.23, 1.17-1.28 [9 studies]), non-smoker (1.28, 1.11-1.47 [7 studies]), of a higher social class (1.20, 1.06-1.36 [2 studies]), having a higher education (1.12, 1.04-1.21 [14 studies]), having a higher household income (1.11, 1.05-1.18 [8 studies]), having a chronic illness (1.53, 1.44-1.63 [16 studies]), having poor self-assessed health (1.23, 1.02-1.40 [9 studies]), having a family doctor (2.94, 1.79-4.76 [2 studies]), and having health insurance (1.58, 1.13-2.21 [6 studies]). The influence of these factors varied across geographical regions. Being older (1.26, 1.11-1.44 [2 studies]) was also associated with increased vaccination adherence., Conclusions: Several factors may determine SIV uptake and vaccination adherence among older people. More studies are needed to provide a stronger evidence base for planning more effective influenza vaccination programs., Competing Interests: AC and ET are employees of Sanofi Pasteur. SMM has received unrestricted research grants from GlaxoSmithKline, Merck, Sanofi Pasteur, Pfizer and Roche-Assurex for unrelated studies, and fees as an advisory board member for Sanofi Pasteur. This study was also partially funded through a research grant from Sanofi Pasteur USA for a related, and already published, study. This does not alter our adherence to PLOS ONE policies on sharing data and materials. There are no patents, products in development or marketed products to declare.

Introduction: Despite improved understanding of the risks of influenza and better vaccines for older patients, influenza vaccination rates remain subpar, including in high-risk groups such as older adults, and demonstrate significant racial and ethnic disparities., Methods: This study considers demographic, clinical, and geographic correlates of influenza vaccination among Medicare Fee-for-Service (FFS) beneficiaries in 2015-2016 and maps the data on a geographic information system (GIS) at the zip code level., Results: Analyses confirm that only half of the senior beneficiaries evidenced a claim for receiving an inactivated influenza vaccine (IIV), with significant disparities observed among black, Hispanic, rural, and poorer beneficiaries. More extensive disparities were observed for the high-dose (HD) vaccine, with its added protection for older populations and confirmed economic benefit. Most white beneficiaries received HD; no non-white subgroup did so. Mapping of the data confirmed subpar vaccination in vulnerable populations with wide variations at the zip code level., Conclusion: Urgent and targeted efforts are needed to equitably increase IIV rates, thus protecting the most vulnerable populations from the negative health impact of influenza as well as the tax-paying public from the Medicare costs from failing to do so.

Background: In children with epilepsy, fever and illness are known triggers for seizure; therefore, clinicians and parents could be concerned that immunization-induced inflammation and fever could also trigger seizures. We sought to estimate the risk of emergency department (ED) visit or hospitalization for epilepsy/seizure and all causes after immunization in children younger than 7 years of age with epilepsy., Methods: We conducted a self-controlled case series of children diagnosed with epilepsy before their 7th birthday and immunized from 2005 to 2015 in Ontario (population 14.2 million) and Manitoba (population 1.3 million), Canada, using administrative healthcare data. We estimated the age- and season-adjusted relative incidence (aRI) of epilepsy/seizure-related and all-cause ED visits/hospitalizations during various risk periods 0-28 days after inactivated and live immunizations versus a control period 35-83 days postimmunization. Estimates from each province were analyzed separately and then combined in a random-effects meta-analysis., Results: The combined risk of epilepsy/seizure-related hospitalization/ED visit was increased 0-2 days after inactivated vaccines (aRI = 1.5, 95% confidence interval: 1.1-1.9) and 7-10 days after live vaccines (aRI = 1.9, 1.4-2.7). For all-cause ED visit/hospitalization, the combined aRI estimate was 0.9 (0.8-1.2) 0-2 days after inactivated vaccines and 1.3 (1.1-1.5) 7-10 days after live vaccines., Conclusions: The risk of epilepsy/seizure-related ED visit/hospitalization was modestly increased among children with epilepsy during peak periods of fever and inflammation following inactivated and live vaccines. These risks must be balanced against the risk of complications from vaccine-preventable diseases.

Objective: To compare the economic impact of high-dose trivalent (HD) versus standard-dose trivalent (SD) influenza vaccination on direct medical costs for cardio-respiratory hospitalizations in adults aged 65 years or older enrolled in the United States (US) Veteran's Health Administration (VHA)., Methods: Leveraging a relative vaccine effectiveness study of HD versus SD over five respiratory seasons (2010/11 through 2014/15), we collected cost data for healthcare provided to the same study population both at VHA and through Medicare services. Our economic assessment compared the costs of vaccination and hospital care for patients experiencing acute cardio-vascular or respiratory illness., Results: We analyzed 3.5 million SD and 158,636 HD person-seasons. The average cost of HD and SD vaccination was $23.48 (95% CI: $21.29 - $25.85) and $12.21 (95% CI: $11.49 - $13.00) per recipient, respectively, while the hospitalization rates for cardio-respiratory disease in HD and SD recipients were 0.114 (95% CI: 0.108-0.121) and 0.132 (95% CI: 0.132-0.133) per person-season, respectively. Attributing the average cost per hospitalization of $11,796 (95% CI: $11,685 - $11,907) to the difference in hospitalization rates, we estimated savings attributable to HD to be $202 (95% CI: $115 - $280) per vaccinated recipient., Conclusions: For the five-season period of 2010/11 through 2014/15, HD influenza vaccination was associated with net cost savings due to fewer hospitalizations, and therefore lower direct medical costs, for cardio-respiratory disease as compared to SD influenza vaccination in the senior US VHA population., (Copyright © 2019 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: Observational studies of the relative effectiveness of influenza vaccines are essential for public health decision making. Their estimates, however, are subject to bias due to unmeasured confounders. Instrumental variable (IV) methods can control for observed and unobserved confounders., Methods: We used linked electronic medical record databases in the Veterans Health Administration (VHA) as well as Medicare administrative files to examine the relative vaccine effectiveness (rVE) of high-dose influenza vaccine (HD) versus standard-dose influenza vaccines (SD) in preventing hospitalizations among VHA-enrolled Veterans ≥65 years of age during 5 influenza seasons (2010-2011 through 2014-2015). Using multivariable IV Poisson regression modeling to address unmeasured confounding and bias, we analyzed the data by each season and through longitudinal analysis of all five seasons., Findings: We included 3,638,924 person-influenza seasons of observation where 158,636 (4%) were among HD vaccine recipients and 3,480,288 (96%) were among SD vaccine recipients. Of the 1,728,562 Veterans, 1,702,824 (98.5%) were male and 1,299,412 (75%) were non-Hispanic white. Based on the longitudinal analysis of all five seasons, the IV-adjusted rVE estimate of HD vs. SD was 10% (95% CI, 8-12%) against all-cause hospitalization; 18% (95% CI, 15-21%) against cardiorespiratory-associated hospitalization; and 14% (95% CI, 6-22%) against influenza/pneumonia-associated hospitalization. The findings by season were similar., Interpretation: Our analysis of VHA clinical data collected from approximately 1.7 million Veterans 65 years and older during five seasons demonstrates that high-dose influenza vaccine is more effective than standard-dose influenza vaccines in preventing influenza- or pneumonia-associated hospitalizations, cardiorespiratory hospitalizations, and all-cause hospitalizations., (Published by Elsevier Ltd.)

Background: We estimate vaccine effectiveness (VE) against both influenza A/subtypes and B/lineages in Canada for the 2011-2012 trivalent inactivated influenza vaccine (TIV) with components entirely unchanged from the 2010-2011 TIV 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-(adjusted)OddsRatio] × 100 for RT-PCR-confirmed influenza in vaccinated vs nonvaccinated 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% confidence interval [CI], 52%-92%): circulating viruses were HI-characterized as vaccine-matched and bore just 2 aminoacid (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%) in total: 71% (95% CI, 40%-86%) for lineage-matched B/Victoria and 27% (95% CI, -21% to 56%) for lineage-mismatched B/Yamagata. For both influenza A and B types, VE was similar among recipients of either 2010-2011 or 2011-2012 TIV alone, higher when vaccinated both seasons., Conclusions: Phenotypic and genotypic characterization of circulating and vaccine viruses enhances understanding of TIV performance, shown in 2011-2012 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.

Purpose: Effectiveness of the quadrivalent human papillomavirus (QHPV) vaccine against cervical dysplasia has not been estimated using population-based individual level data. We assessed the vaccine effectiveness (VE) of the QHPV vaccine against cervical dysplasia using data collected routinely in Manitoba., Methods: Females ≥ 15 years old who received the QHPV vaccine in Manitoba between September 2006 and April 2010 privately (n = 3,541) were matched on age to up to three nonvaccinated females (n = 9,594). We used Cox regression models to estimate the hazard ratios for three outcomes: atypical squamous cells of undetermined significance (ASCUS), low-grade squamous intraepithelial lesions (LSILs), and high-grade SILs (HSILs)., Results: Among the 15- to 17-year-olds, the adjusted VE estimates were 35% (95% CI, -19% to 65%), 21% (-10% to 43%), and -1% (-44% to 29%) against the detection of HSILs, LSILs, and ASCUS, respectively. The corresponding estimates were higher (46% [0% to 71%], 35% [10% to 54%], and 23% [-8% to 45%]) among those who had ≥ one Pap smear after enrollment. The QHPV vaccine was associated with 23% (-17% to 48%) reduction in HSIL risk among those ≥ 18 with no history of abnormal cytology, but there was no evidence of protection among those with such a history (-8% [-59% to 27%])., Conclusion: A significant percentage of vaccinated women may not be protected against HSIL and lesser dysplasia especially if they were vaccinated at older age (≥ 18) or had abnormal cytology before vaccination. These findings affirm the importance of vaccination before any significant exposure to HPV occurs and underscore the need for screening programs that cover all sexually active women, even if they were vaccinated.

Background: Females who receive the human papillomavirus (HPV) vaccine may believe they are protected from developing cervical cancer and no longer require screening. Concern has also been expressed that vaccinated females are those that would be screened regularly. This study assesses the Pap testing behavior of vaccinated and non-vaccinated females., Methods: For this population-based retrospective cohort study, vaccination and screening registries were linked for 3540 vaccinated females aged 15 years and over and 9592 matched non-vaccinated females. Conditional logistic regression, the Kaplan-Meier method and Cox regression were used to examine the association between vaccination and Pap testing., Results: Vaccinated females were more likely to have had a Pap test within the year prior to the index date than non-vaccinated females (15-19 years old: OR=1.38, 95% CI 1.20-1.59; 20+ years old: OR=2.34, 95% CI 1.98-2.76). In the three-year period after the index date, vaccinated females had a significantly higher cumulative probability of having a Pap test (83.3%) than non-vaccinated females (66.1%). Females who had a Pap test within three years prior to the index date were more likely to have a Pap test after the index date (vaccinated: HR=5.03, 95% CI 4.65-5.45; non-vaccinated HR=3.97, 95% CI 3.70-4.24). Being vaccinated had a significant effect on Pap testing (15-19 years old: HR=1.54, 95% CI 1.39-1.69; 20+ years old: HR=1.87, 95% CI 1.52-2.31). 80.1% of vaccinated females who had a Pap test prior to the index date also had one subsequent to it, compared to 70.1% for non-vaccinated females. 41.1% of females had not been vaccinated nor had a Pap test., Conclusion: The majority of vaccinated females continue to participate in screening, and do so at a higher rate than non-vaccinated females. Renewed efforts need to be made to include the large proportion of non-vaccinated, non-screened females in vaccination and/or screening., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

BACKGROUND. Varicella-zoster virus (VZV) is under consideration as a promising recombinant viral vector to deliver foreign antigens including HIV. However, new vectors have come under increased scrutiny, since trials with adenovirus serotype 5-vectored (Ad5-vectored) HIV vaccine demonstrated increased HIV risk in individuals with pre-immunity to the vector that was thought to be associated with mucosal immune activation (IA). Therefore, given the prospect of developing an HIV/VZV chimeric vaccine, it is particularly important to define the impact of VZV vaccination on IA. METHODS. Healthy VZV-seropositive Kenyan women (n = 44) were immunized with high-dose live attenuated VZV vaccine, and we assessed the expression on [CD4.sup.+] T cells isolated from blood, cervix, and rectum of IA markers including CD38 and HLA-DR and of markers of cell migration and tissue retention, as well as the concentration of genital and intestinal cytokines. A delayed-start group (n = 22) was used to control for natural variations in these parameters. RESULTS. Although immunogenic, VZV vaccination did not result in significant difference in the frequency of cervical activated (HLA-[DR.sup.+][CD38.sup.+]) [CD4.sup.+] T cells (median 1.61%, IQR 0.93%-2.76%) at 12 weeks after vaccination when compared with baseline (median 1.58%, IQR 0.75%-3.04%), the primary outcome for this study. VZV vaccination also had no measurable effect on any of the IA parameters at 4, 8, and 12 weeks after vaccination. CONCLUSION. This study provides the first evidence to our knowledge about the effects of VZV vaccination on human mucosal IA status and supports further evaluation of VZV as a potential vector for an HIV vaccine. TRIAL REGISTRATION. ClinicalTrials.gov NCT02514018. FUNDING. Primary support from the Canadian Institutes for Health Research (CIHR). For other sources, see Acknowledgments., Introduction Previous phase IIb/III HIV vaccine trials attest to the challenges faced in human immunodeficiency virus (HIV) vaccine development. The use of adenovirus serotype 5 (Ad5) as a recombinant viral [...]

Background: The incidence of anogenital warts (AGW) decreased after the introduction of the quadrivalent human papillomavirus (qHPV) vaccine in multiple jurisdictions. We studied how comparing AGW incidence rates with different outcomes affects the interpretation of the qHPV vaccination program. To do this, we replicated multiple study designs within a single jurisdiction (Manitoba). Methods: We measured the incidence rates of AGW, AGW-related prescriptions, chlamydia, and gonorrhea (the latter two as sham outcomes) between 2001 and 2017 using several clinical and administrative health databases from Manitoba. We then used incidence rate ratios (IRRs) to compare, for each outcome, the rate for the 1997–1998 birth cohort (the first cohorts eligible for the publicly funded qHPV vaccination program) and the older 1995–1996 birth cohort. Results: AGW incidence in Manitoba dropped 72% (95% confidence interval 54–83%) among 16–18 year-old girls and 51% (14–72%) among boys after the introduction of the female-only qHPV vaccination program. Trends in AGW-related prescriptions were different from trends in AGW diagnoses as these prescriptions peaked shortly after the introduction of the publicly funded qHPV vaccine program. Chlamydia and gonorrhea incidence rates also decreased 12% (5–18%) and 16% (-1-30%), respectively, for 16–18 year-old girls. Conclusions: The publicly funded school-based qHPV vaccine program reduced AGW incidence in Manitoba by three-quarters in young females. AGW-related prescriptions are a poor proxy for medically attended AGW after the introduction of the publicly funded qHPV vaccination program. Different sexual habits in adolescents are, at most, responsible for a small portion of the reduction in AGW incidence. [ABSTRACT FROM AUTHOR]

Background: Seasonal influenza vaccination (SIV) rates remain suboptimal in many populations, even in those with universal SIV.Objective: To summarize the evidence on interventions on health care providers (physicians/nurses/pharmacists) to increase SIV rates.Methods: We systematically searched/selected full-text English publications from January 2000 to July 2019 (PROSPERO-CRD42019147199). Our outcome was the difference in SIV rates between patients in intervention and non-intervention groups. We calculated pooled difference using an inverse variance, random-effects model.Results: We included 39 studies from 8370 retrieved citations. Compared with no intervention, team-based training/education of physicians significantly increased SIV rates in adult patients: 20.1% [7.5-32.7%; I2 = 0%; two randomized controlled trials (RCTs)] and 13.4% [8.6-18.1%; I2 = 0%; two non-randomized intervention studies (NRS)]. A smaller increase was observed in paediatric patients: 7% (0.1-14%; I2 = 0%; two NRS), and in adult patients with team-based training/education of physicians and nurses together: 0.9% (0.2-1.5%; I2 = 30.6%; four NRS). One-off provision of guidelines/information to physicians, and to both physicians and nurses, increased SIV rates in adult patients: 23.8% (15.7-31.8%; I2 = 45.8%; three NRS) and paediatric patients: 24% (8.1-39.9%; I2 = 0%; two NRS), respectively. Use of reminders (prompts) by physicians and nurses slightly increased SIV rates in paediatric patients: 2.3% (0.5-4.2%; I2 = 0%; two RCTs). A larger increase was observed in adult patients: 18.5% (14.8-22.1%; I2 = 0%; two NRS). Evidence from both RCTs and NRS showed significant increases in SIV rates with varied combinations of interventions.Conclusions: Limited evidence suggests various forms of physicians' and nurses' education and use of reminders may be effective for increasing SIV rates among patients. [ABSTRACT FROM AUTHOR]

Introduction: Vaccination is considered to be the most practical and effective preventative measure against influenza. It is highly recommended for population subgroups most at risk of developing complications, including pregnant women. However, seasonal influenza vaccine uptake remains suboptimal among pregnant women, even in jurisdictions with universal vaccination. We summarized the evidence on the determinants of seasonal influenza vaccine uptake during pregnancy to better understand factors that influence vaccine uptake among pregnant women. Material and methods: We systematically searched MEDLINE, Embase and CINAHL from January 2000 to February 2020 for publications in English reporting on sociodemographic and/or health‐related determinants of seasonal influenza vaccine uptake during pregnancy. Two reviewers independently included studies. One reviewer extracted data and assessed study quality, and another reviewer checked extracted data and study quality assessments for errors. Disagreements were resolved through consensus, or a third reviewer. We meta‐analyzed using the inverse variance, random‐effects method, and reported the odds ratios (OR) and 95% confidence intervals (CI). Results: From 1663 retrieved citations, we included 36 studies. The following factors were associated with increased seasonal influenza vaccine uptake: Older age (20 studies: OR 1.13, 95% CI 1.07‐1.20), being nulliparous (13 studies: OR 1.26, 95% CI 1.15‐1.38), married (8 studies: OR 1.11, 95% CI 1.07‐1.15), employed (4 studies: OR 1.13, 95% CI 1.02‐1.24), a non‐smoker (8 studies: OR 1.25, 95% CI 1.04‐1.51) and having prenatal care (3 studies: OR 3.36, 95% CI 2.25‐5.02), a chronic condition (6 studies: OR 1.30, 95% CI 1.17‐1.44), been previously vaccinated (9 studies: OR 4.88, 95% CI 3.14‐7.57) and living in a rural area (9 studies: OR 1.09, 95% CI 1.05‐1.14). Compared with being black, being white was also associated with increased seasonal influenza vaccine uptake (11 studies: OR 1.30, 95% CI 1.20‐1.41). Conclusions: The evidence suggests that several sociodemographic and health‐related factors may determine seasonal influenza vaccination in pregnancy, and that parity, history of influenza vaccination, prenatal care and comorbidity status may be influential. [ABSTRACT FROM AUTHOR]

To investigate a potential risk for multiple sclerosis (MS) after vaccination with Arepanrix, the GlaxoSmithKline AS03-adjuvanted influenza A(H1N1)pdm09 vaccine, we used the provincewide immunization registry for Manitoba, Canada, to match 341,347 persons vaccinated during the 2009 pandemic to 485,941 unvaccinated persons on age, sex, address, and a propensity score measuring the probability of vaccination. We used a previously validated algorithm to identify MS cases from provincial hospital, physician, and prescription drug claims databases. After 12 months of follow-up, the age-adjusted incidence rate of MS was 17.7 cases per 100,000 person-years in the Arepanrix cohort and 24.2 per 100,000 in the unvaccinated cohort. The corresponding adjusted hazard ratio was 0.9. We observed similar patterns when we measured incidence over the entire follow-up period. The AS03 adjuvant, a candidate for inclusion in future pandemic vaccines, does not appear to increase the short-term risk for MS when included in influenza vaccines. [ABSTRACT FROM AUTHOR]

Background: 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.Methods: 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.Results: 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%.Conclusion: ICD-9 codes from physician billing claims data have low sensitivity and moderate specificity to identify laboratory-confirmed pertussis among persons tested for pertussis. [ABSTRACT FROM AUTHOR]

Background: 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. Methods: 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. Results: 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. Discussion: 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). [ABSTRACT FROM AUTHOR]

The article presents information on a study which examined the expected effect of human papillomavirus (HPV) vaccination on cervical cancer screening and a possible new strategy that integrates novel molecular-based screening technologies. It discusses the immediate and long-term effects of HPV vaccination. References to other research studies on alternatives to primary screening with traditional Pap cytology are discussed. Other topics discussed include advantages to adopting the HPV Pap triage strategy for cervical cancer screening, and the need to redesign screening programs.

We used modeling approaches to estimate the impact of human papillomavirus (HPV) vaccination on the performance of Pap cytology screening under different assumptions of lesion prevalence and expected changes in sensitivity and specificity likely to prevail post-vaccination. A major driver of the efficiency and costs of screening, the positive predictive value will be severely affected if Pap cytology continues to serve as the primary screening test in the post-vaccination era. Molecular-based screening with an HPV DNA test followed by Pap triage of HPV-positive cases has the potential for circumventing this problem. As a primary screening test, HPV testing can improve the overall quality of screening programs, thus allowing for increased testing intervals that would lower program costs with acceptable safety. Cytology should be reserved for the more labor-efficient task of triaging HPV-positive cases, a situation in which case loads would be “enriched” with smears containing relevant abnormalities. HPV followed by Pap strategy can also serve a secondary role in post-vaccination surveillance. [Copyright &y& Elsevier]

In 1960, it was discovered that Simian Virus 40 (SV40) contaminated up to 30% of the poliovirus vaccines in the US. This contamination arose because the vaccines were produced in monkey kidney cell cultures harboring SV40 between 1955 and 1963. During this period, approximately 90% of children and 60% of adults in the USA were inoculated for polio and possibly exposed to SV40. Many epidemiologic and molecular pathogenesis studies have been conducted in order to identify potential cancer risks since this ‘natural’ experiment began. Productive SV40 infection has the potential to initiate malignancy in a variety of target tissues. Epidemiological studies that investigated the relationship between SV40 infection and cancer risks have yielded mixed results. Studies can be grouped into three categories based on their exposure definition of SV40 infection: (1) use of vaccination or birth cohorts as proxy variables for infection, (2) follow-up of children of pregnant women who received polio vaccines, and (3) direct molecular detection of the virus or serologic detection of anti-SV40 antibody responses. A meta-analysis of five published studies did not support the hypothesis that SV40 exposure increases the overall risk of cancer incidence or cancer mortality. The analysis of specific cancer sites is largely inconclusive because of substantial problems that most studies have had in reliably defining exposure, defining latency effects, or dealing with confounding and other biases. A new generation of molecular epidemiologic studies is necessary to properly address these issues.Oncogene (2004) 23, 6535-6540. doi:10.1038/sj.onc.1207877 [ABSTRACT FROM AUTHOR]

• An interrupted time series analysis of impact of USIVP in Manitoba. • Increased absolute change in SIV uptake percentage in the lowest income quintiles and with less healthcare utilization among 5–17-year-olds. • An upward annual trend in SIV uptake percentage among 5–17-year-olds. • A downward annual trend in SIV uptake percentage among 45–64-year-olds. • A downward annual trend across all strata of assessed population characteristics within all age groups in Northern Manitoba. Universal seasonal influenza vaccination policy (USIVP) was introduced in Manitoba, Canada in 2010. Its impact on seasonal influenza vaccine (SIV) uptake remains underexplored. We used population-wide data from Manitoba to assess the impact of the USIVP on SIV uptake. The study covered twenty influenza seasons (2000/01–2019/20). We summarized SIV uptake for influenza seasons before and after the USIVP. Utilizing a single-group interrupted time series analysis and appropriately accounting for autocorrelation, we estimated absolute change and annual trend in SIV uptake percentages among 5–17-, 18–44-, and 45–64-year-olds across strata of certain population socioeconomic and health-related characteristics following the USIVP. Average SIV uptake percentage in all age groups was significantly higher after compared with before the USIVP. Following the USIVP, there was no significant absolute change in SIV uptake percentage among 18–44- and 45–64-year-olds overall; however, a significant decrease was observed among 18–44-year-old males in the higher income quintiles, across healthcare utilization, and in some regions of residence. A significant increase was observed among 5–17-year-olds in the lowest income quintiles, in Northern Manitoba, and among those with less healthcare utilization, and no chronic disease. Overall, there was mostly no significant annual trend in SIV uptake percentage among 18–44-year-olds, and while a significant upward and downward trend was observed among 5–17-year-olds and 45–64-year-olds, respectively, a significant downward trend was observed across all strata of population characteristics within all age groups in Northern Manitoba. The USIVP in Manitoba was followed by an absolute increase in SIV uptake percentage only in some socioeconomically disadvantaged subpopulations among 5–17-year-olds. While there was mostly an upward annual trend in SIV uptake percentage among 5–17-year-olds, a downward trend was observed among 45–64-year-olds and across all age groups and subpopulations in socioeconomically disadvantaged Northern Manitoba. These findings are novel for Manitoba and require investigation and public health attention. [ABSTRACT FROM AUTHOR]

• Assessed impact of universal seasonal influenza vaccination policy on seasonal influenza vaccine uptake in Manitoba, Canada. • Significantly increased odds of vaccination 5-years post-policy relative to pre-policy among age groups except ≥65-year-olds. • Mostly homogeneous effect estimates within age groups across strata of assessed socioeconomic/health-related characteristics. • Largely consistent findings irrespective of sex and region of residence. In 2010, the government of the province of Manitoba, Canada introduced universal seasonal influenza vaccination policy (USIVP), providing free-of-charge vaccination to all registered residents of the province at least six months of age. Impact of the policy on seasonal influenza vaccine (SIV) uptake (receipt of vaccine) in Manitoba remains unclear, as there is a lack of published evaluations. We conducted an ecological study, utilizing population-wide data from several linked de-identified Manitoba Health and Seniors Care administrative health databases. The study period was from 2000/01–2019/20 influenza seasons. The primary exposure was USIVP (five influenza seasons pre-policy [2005/06–2009/10] compared with post-policy [2010/11–2014/15]). The outcome was SIV uptake. We conducted pre/post logistic regression analysis stratified by age group (<5-, 5–17-, 18–44-, 45–64-, ≥65-year-olds) and certain population socioeconomic and health-related characteristics. Results are adjusted odds ratios with associated 95 % confidence intervals. We observed significantly increased adjusted odds of SIV uptake post-policy relative to pre-policy in all age groups except ≥65-year-olds already covered from inception of the vaccination programme. The adjusted odds ratios ranged from 0.76 (0.75–0.76) among ≥65-year-olds to 2.15 (2.13–2.18) among 5–17-year-olds, and were largely homogeneous within age groups across sex, income quintiles, regions of residence, and categories of number of visits to primary care physician/hospitalization one year prior to an influenza season except among <5- and 5–17-year-olds. These findings were mostly consistent irrespective of sex and region of residence although there was variability across income quintiles in Northern Manitoba region. Introduction of the USIVP in Manitoba was followed by a significant increase in SIV uptake in the five years post policy among <65-year-olds, with similar increased relative odds of vaccination observed within age groups across subpopulations. The observed variations in the relative odds of vaccination across income quintiles in Northern Manitoba region requires administrative attention. [ABSTRACT FROM AUTHOR]

• Comparison of vaccine uptake in 2 and 7 year-old children with and without epilepsy. • Vaccine coverage is similar between children with and without epilepsy. • Children diagnosed early have slightly lower vaccine coverage at age 2 years. Children with epilepsy are at increased risk of complications from vaccine-preventable infections, yet information on vaccine coverage in these children is scarce. We aimed to compare vaccine coverage among children with epilepsy to children without epilepsy. We conducted a retrospective cohort study including all 2005–2013 births in Manitoba and Ontario, Canada, creating two cohorts: 2-year-olds and 7-year-olds (followed to age 2 and 7 years). We split each cohort into epilepsy and non-epilepsy subcohorts. We assessed vaccination coverage based on provincial schedules and determined timeliness of MMR (measles, mumps, rubella) dose 1 (recommended at 12 months) and DTaP (diphtheria, tetanus, pertussis) dose 4 (recommended at 18 months). We used logistic regression to calculate adjusted odds ratios (aORs) of the association between epilepsy and vaccination, combining both provincial estimates using random effects meta -analysis. We included 16,558 2-year-olds (Manitoba, 653; Ontario, 15,905) and 13,004 7-year-olds (Manitoba, 483; Ontario, 12,521) with epilepsy. At age 2 years, the aOR for up-to-date vaccination among children with versus without epilepsy was 0.9 (95% confidence interval 0.8–1.1); at age 7 years it was 1.0 (0.9–1.1). Infants diagnosed with epilepsy before age 6 months were less likely to be up-to-date at age 2 years (0.9; 0.8–0.9), although this difference disappeared by age 7 years. Vaccine timeliness was similar between children with and without epilepsy for MMR dose 1 and DTaP dose 4. Overall, this study suggests that children with epilepsy are not significantly under-vaccinated compared to their peers without epilepsy. As children with epilepsy are at a higher risk of complications from vaccine-preventable diseases, vaccination in children with epilepsy should be optimized, especially early in life, as these children may not be able to rely on herd protection. [ABSTRACT FROM AUTHOR]

• A nested case-control study measuring pertussis vaccine effectiveness (VE). • Acellular pertussis vaccine was effective in preventing disease. • There was a possible decline in protection 8 years post-vaccination. • VE was lower during a large outbreak. • Outbreak periods should be analyzed separately in VE studies. Pertussis persists in Manitoba despite the universal availability of pertussis vaccines. Recent cases have included previously vaccinated individuals, raising concerns about declining vaccine effectiveness (VE). We measured pertussis VE and duration of protection using Manitoba's provincial immunization and communicable disease registries. Using a nested case-control design, individuals with laboratory-confirmed pertussis in Manitoba diagnosed between April 1, 1992, and March 31, 2015, were matched to up to five population-based controls on age, gender, geography, and case physician or number of physician visits. Conditional logistic regression was used to estimate VE against pertussis for both the whole-cell (wP) and acellular (aP) pertussis vaccines. Duration of protection was assessed using time since last dose. Data on 534 eligible cases and 2614 controls were available for analysis. The adjusted VE estimate for aP-containing vaccines was 85% (95%CI: 74–91%); VE was 89% (66–96%) one to three years after the last vaccination. The adjusted VE of wP-containing vaccines was –15% (–91–31%) during a large outbreak in 1994 and 1995 compared to 35% (–26–66%) during non-outbreak years. Our estimates suggest that the aP vaccine was effective in preventing pertussis since its introduction in Manitoba. VE was lower during a large outbreak, highlighting the importance of separately analyzing outbreak periods when estimating pertussis VE over time. [ABSTRACT FROM AUTHOR]