Influenza Immunization Program Research Articles

Evaluación de una novedosa campaña de vacunación de la gripe en personal sanitario en la temporada 2011-2012

The objective was to evaluate the healthcare personnel seasonal influenza immunization program in the 2011-2012 flu season. The campaign included several innovative actions (informational brochure, recommendations for unvaccinated staff to wear a mask, acknowledgement letters, etc). Coverage and characteristics of the health personnel were compared with the previous season using the chi-square test. Vaccination coverage for the 2011-12 flu season was 26.5%, compared to 24.5% achieved in 2010-2011 (p=0.052). The improvement in vaccination coverage approached statistical significance but remains very low. To improve these low vaccination levels, we recommend developing other strategies, such as incentive policies or making vaccination mandatory.

Why Influenza Viruses Continue to Pose a Significant Threat to Aging and Aged Populations Worldwide

While influenza immunization programs are the most effective prophylactic public health tools in protecting vulnerable populations worldwide, influenza infections still remain a threat in industrialized countries. This becomes particularly apparent in aging and aged populations, and mostly results from complex changes in the immune system occurring with advancing age. This review will present important recent findings on the interaction of the immune system and influenza antigens, with a specific emphasis on how the age-associated changes within the immune system blunt the immune response to influenza vaccines. Furthermore, our current knowledge and understanding of vaccine responsiveness in the elderly will be detailed. Finally, this review will present some possible options for vaccine development to enhance capacities of the senescent immune system to deal with influenza antigen, in order to keep older members of our society autonomous and independent, and to contribute to healthy aging.

Feasibility of a Pharmacy-Based Influenza Immunization Program in an Academic Emergency Department

From September 2002 to August 2010, 13 patients who were discharged from the emergency department (ED) were immunized against influenza. This correlates with a time when pharmacists were not permitted to vaccinate patients in New York. The objectives of this study were to determine the feasibility of a pharmacist-based influenza vaccination program in the ED, assess patients' willingness to be vaccinated by a pharmacist, and identify reasons for declination. This was a cross-sectional study involving English-speaking patients older than 18 years. The pharmacist vaccinated patients, if they consented. Patients who refused to be vaccinated were asked why they did not want to receive the vaccine and their perception of pharmacists vaccinating patients in the ED. The percentage of patients vaccinated; time elements associated with the process of screening, counseling, and vaccinating; and the type and frequency of adverse events were recorded. Of 149 patients, 62 patients (41%) agreed to receive the vaccine, a 4-fold increase from the previous 8 years. The median screening and vaccination time was 8 minutes. Of those not receiving a vaccine in the ED, 74% were willing to receive the influenza vaccine from a pharmacist, and 78% were willing to receive the vaccine in the ED. The most common reason for refusal was perception of low self-risk (43.9%). No adverse events were reported. A pharmacist-based influenza immunization program is feasible in the ED and has the potential to successfully and safely increase the percentage of adult patients receiving the vaccine.

Universal flu vaccination for children gets underway

INFLUENZA Workloads will increase but benefits should include fewer cases and lower mortality rates. Laura Craig, explains the influenza immunisation programme

Universal flu vaccination for children gets underway

Workloads will increase but benefits should include fewer cases and lower mortality rates. Laura Craig, explains the influenza immunisation programme.

Immunizing health care workers against influenza: A glimpse into the challenges with voluntary programs and considerations for mandatory policies

Vaccination of health care workers (HCWs) is an important patient safety initiative. It prevents influenza infection among patients and reduces staff illness and absenteeism. Despite these benefits, HCW influenza immunization uptake is low. Therefore, strategies to achieve high immunization coverage in HCWs, barriers to uptake, and perceptions of mandatory influenza immunization policies were discussed in key informant interviews with influenza immunization program planners. We conducted telephone interviews with 23 influenza immunization program planners from 21 organizations (7 acute care hospitals, 6 continuing care facilities, and 8 public health organizations) across Canada. We used content analysis to identify themes from the interviews. Participants used a variety of promotional and educational activities, and many vaccine delivery approaches, to support HCW immunization programs. Barriers to achieving high coverage in HCWs included misconceptions about the safety and effectiveness of the influenza vaccine, negative personal experiences associated with the vaccine, and antivaccine sentiments. Participants mentioned mandatory influenza immunizations as a solution to low coverage. However, they identified challenges with this approach such as obtaining support from stakeholders, enforcement, and limiting personal autonomy. Participants believed immunization coverage in health care organizations will continue to be suboptimal using existing program strategies. Although participants discussed mandatory immunization as a way to improve uptake, potential obstacles will need to be addressed for this to be implemented successfully.

Hospital-based cluster randomised controlled trial to assess effects of a multi-faceted programme on influenza vaccine coverage among hospital healthcare workers and nosocomial influenza in the Netherlands, 2009 to 2011

Nosocomial influenza is a large burden in hospitals. Despite recommendations from the World Health Organization to vaccinate healthcare workers against influenza, vaccine uptake remains low in most European countries. We performed a pragmatic cluster randomised controlled trial in order to assess the effects of implementing a multi-faceted influenza immunisation programme on vaccine coverage in hospital healthcare workers (HCWs) and on in-patient morbidity. We included hospital HCWs of three intervention and three control University Medical Centers (UMCs), and 3,367 patients. An implementation programme was offered to the intervention UMCs to assess the effects on both vaccine uptake among hospital staff and patient morbidity. In 2009/10, the coverage of seasonal, the first and second dose of pandemic influenza vaccine as well as seasonal vaccine in 2010/11 was higher in intervention UMCs than control UMCs (all p<0.05). At the internal medicine departments of the intervention group with higher vaccine coverage compared to the control group, nosocomial influenza and/or pneumonia was recorded in 3.9% and 9.7% of patients of intervention and control UMCs, respectively (p=0.015). Though potential bias could not be completely ruled out, an increase in vaccine coverage was associated with decreased patient in-hospital morbidity from influenza and/or pneumonia.

Swine influenza and vaccines: an alternative approach for decision making about pandemic prevention

During the global pandemic of A/H1N1/California/07/2009 (A/H1N1/Cal) influenza, many governments signed contracts with vaccine producers for a universal influenza immunization program and bought hundreds of millions of vaccines doses. We argue that, as Health Ministers assumed the occurrence of the worst possible scenario (generalized pandemic influenza) and followed the strong version of the Precautionary Principle, they undervalued the possibility of mild or weak pandemic wave. An alternative decision rule, based on the non-extensive entropy principle, is introduced, and a different Precautionary Principle characterization is applied. This approach values extreme negative results (catastrophic events) in a different way and predicts more plausible and mild events. It introduces less pessimistic forecasts in the case of uncertain influenza pandemic outbreaks. A simplified application is presented using seasonal data of morbidity and severity among Italian children influenza-like illness for the period 2003-10. Established literature results predict an average attack rate of not less than 15% for the next pandemic influenza [Meltzer M, Cox N, Fukuda K. The economic impact of pandemic influenza in the United States: implications for setting priorities for interventions. Emerg Infect Dis 1999;5:659-71; Meltzer M, Cox N, Fukuda K. Modeling the Economic Impact of Pandemic Influenza in the United States: Implications for Setting Priorities for Intervention. Background paper. Atlanta, GA: CDC, 1999. Available at: http://www.cdc.gov/ncidod/eid/vol5no5/melt_back.htm (7 January 2011, date last accessed))]. The strong version of the Precautionary Principle would suggest using this prediction for vaccination campaigns. On the contrary, the non-extensive maximum entropy principle predicts a lower attack rate, which induces a 20% saving in public funding for vaccines doses. The need for an effective influenza pandemic prevention program, coupled with an efficient use of public funding, calls for a rethinking of the Precautionary Principle. The non-extensive maximum entropy principle, which incorporates vague and incomplete information available to decision makers, produces a more coherent forecast of possible influenza pandemic and a conservative spending in public funding.

Development of a Rural Health Framework: Implications for Program Service Planning and Delivery

To describe the development and application of an evidence-based rural health framework to guide rural health program, policy and service planning. A literature review of rural health programs, focusing on health promotion, chronic disease prevention and population health, was conducted using several bibliographic databases. Thirty papers met the criteria for review, describing chronic disease interventions and public health policies in rural settings. Twenty-one papers demonstrated effective intervention programs and highlighted potential good practices for rural health programs, which were used to define key elements of a rural health framework. The rural health framework was applied to an influenza immunization program to demonstrate its utility in assisting public health providers to increase uptake of the vaccine. This rural health framework provides an opportunity for program planners to reflect on the key issues facing rural communities to ensure the development of policies and strategies that will prudently and effectively meet population health needs.

Health care worker influenza immunization rates: The missing pieces of the puzzle

Immunization rates are used to assess the level of protection against influenza, but limited data exist on how such rates are measured in health care organizations. We conducted key informant interviews with campaign planners to learn about processes for collecting immunization data, including barriers and facilitating factors for measuring and reporting rates. We conducted telephone interviews with 23 influenza immunization program planners across Canada working in 7 acute care hospitals, 6 continuing care facilities, and 8 public health organizations in 2012. We used content analysis to examine the interview data. The methods used to collect immunization data varied by the size and type of health care organization. Immunization data from different personnel groups were included in immunization rate calculations depending on the local public health reporting requirements and the organization's size. Challenges associated with collecting immunization data and calculating rates included lack of resources for identifying personnel immunized off-site, tracking personnel who declined immunization, identifying non-payroll staff, and interpreting unclear public health reporting requirements. Support from other vaccine providers, public health, employers, and professional and external bodies is needed to provide the necessary information and resources to calculate accurate and complete rates. Further work is needed to refine and standardize the collection of HCW influenza immunization data so that it may be used for surveillance and quality assessment purposes.

Influenza: a century of science and public health response

In 1976, the outbreak of a new strain of swine flu at the Fort Dix, New Jersey, army base prompted an unprecedented inoculation campaign. Some forty-two million Americans were vaccinated as the National Influenza Immunization Program hastened to prevent a pandemic, while the World Health Organization (WHO) took a wait-and-see approach. Fortunately, the virus did not spread, and only one death occurred. But instead of being lauded, American actions were subsequently denounced as a fiasco and instigator of mass panic. In Influenza, George Dehner examines the wide disparity in national and international responses to influenza pandemics, from the Russian flu of 1889 to the swine flu outbreak in 2009. He chronicles the technological and institutional progress made along the way and shows how these developments can shape an effective future policy. Early pandemic response relied on methods of quarantine and individual scientific research. In the aftermath of World War II, a consensus for cooperation and shared resources led to the creation of the WHO, under the auspices of the United Nations. Today, the WHO maintains a large and proactive role in responding to influenza outbreaks. International pandemic response, however, is only as strong as its weakest national link most recently evidenced in the failed early detection of the 2009 swine flu in Mexico and the delayed reporting of the 2002 SARS outbreak in China. As Dehner s study contends, the hard lessons of the past highlight the need for a coordinated early warning system with full disclosure, shared technologies, and robust manufacturing capabilities. Until the national aspect can be removed from the international equation, responses will be hampered, and a threat to an individual remains a threat to all.

Impact of the raising immunizations safely and effectively (RISE) program on healthcare worker influenza immunization rates in long term care settings.

National influenza immunization rates for healthcare workers (HCW) in long-term care (LTC) remain unacceptably low. This poses a serious public health threat to residents. Prior work has suggested high staff turnover rates as a contributing factor to low immunization rates. There is a critical need to identify and deploy successful models of HCW influenza immunization programs to LTC facilities. This report describes one potential model that has been successfully initiated in a network of LTC facilities. All facilities served by a single regional LTC pharmacy were invited to participate in a HCW influenza immunization program. This voluntary immunization program began in 2005 and continues to the present. As part of the program, the pharmacy promoted organizational change by assuming oversight and control of HCW immunization policies and processes for all facilities. Primary and secondary outcomes are the number of facilities reaching HCW influenza immunization rates of 60% and 80%. Fourteen of the 16 LTC facilities participated. Facilities were diverse and included both nursing and assisted living facilities; unionized and nonunionized facilities; and urban, suburban, and rural facilities. The pharmacy provided educational and communication materials, centralized data collection using a standardized definition for HCW immunization rates, and facility feedback. All 14 LTC facilities achieved the primary goal of 60% and nearly two thirds reached the secondary goal of 80%. Twenty percent reached the new Healthy People 2020 goal of 90%. It is possible for LTC facilities to improve HCW immunization rates using a pharmacy based, voluntary HCW influenza immunization approach. Such an approach may help attenuate the negative influence of staff turnover on HCW immunizations. Attainment of the new Health People 2020 goals still remains a challenge and may require mandatory programs.

Planning influenza vaccination programs: a cost benefit model

BackgroundAlthough annual influenza vaccination could decrease the significant economic and humanistic burden of influenza in the United States, immunization rates are below recommended levels, and concerns remain whether immunization programs can be cost beneficial. The research objective was to compare cost benefit of various immunization strategies from employer, employee, and societal perspectives.MethodsAn actuarial model was developed based on the published literature to estimate the costs and benefits of influenza immunization programs. Useful features of the model included customization by population age and risk-level, potential pandemic risk, and projection year. Various immunization strategies were modelled for an average U.S. population of 15,000 persons vaccinated in pharmacies or doctor’s office during the 2011/12 season. The primary outcome measure reported net cost savings per vaccinated (PV) from the perspective of various stakeholders.ResultsGiven a typical U.S. population, an influenza immunization program will be cost beneficial for employers when more than 37% of individuals receive vaccine in non-traditional settings such as pharmacies. The baseline scenario, where 50% of persons would be vaccinated in non-traditional settings, estimated net savings of $6 PV. Programs that limited to pharmacy setting ($31 PV) or targeted persons with high-risk comorbidities ($83 PV) or seniors ($107 PV) were found to increase cost benefit. Sensitivity analysis confirmed the scenario-based findings.ConclusionsBoth universal and targeted vaccination programs can be cost beneficial. Proper planning with cost models can help employers and policy makers develop strategies to improve the impact of immunization programs.

Low Rates of Influenza Immunization in Young Children Under Ontario’s Universal Influenza Immunization Program

To determine physician-administered influenza vaccine coverage for children aged 6 to 23 months in a jurisdiction with a universal influenza immunization program during 2002-2009 and to describe predictors of vaccination. By using hospital records, we identified all infants born alive in Ontario hospitals from April 2002 through March 2008. Immunization status was ascertained by linkage to physician billing data. Children were categorized as fully, partially, or not immunized depending on the number and timing of vaccines administered. Generalized linear mixed models determined the association between immunization status and infant, physician, and maternal characteristics. Influenza immunization was low for the first influenza season of the study period (1% fully immunized during the 2002-2003 season), increased for the following 3 seasons (7% to 9%), but then declined (4% to 6% fully immunized during the 2006-2007 to 2008-2009 seasons). Children with chronic conditions or low birth weight were more likely to be immunized. Maternal influenza immunization (adjusted odds ratio 4.31; 95% confidence interval 4.21-4.40), having a pediatrician as the primary care practitioner (adjusted odds ratio 1.85; 95% confidence interval 1.68-2.04), high visit rates, and better continuity of care were all significantly associated with full immunization, whereas measures of social disadvantage were associated with nonimmunization. Low birth weight infants discharged from neonatal care in the winter were more likely to be immunized. Influenza vaccine coverage among children aged 6 to 23 months in Ontario is low, despite a universal vaccination program and high primary care visit rates. Interventions to improve coverage should target both physicians and families.

School-located influenza immunization programs: Factors important to parents and students

PurposeTo describe both parent and student perspectives on the importance of various programmatic factors when deciding to participate in a school-located immunizations program (SLIP) for influenza vaccine. MethodsQuestionnaires were distributed to middle- and high-school students and their parents; the document assessed demographic data, influenza vaccination history, and the importance of various factors in their decision to participate in a potential SLIP for influenza vaccine. Factor analysis created six primary factors of importance related to programming: (1) safety/trust; (2) outbreaks (representing imminent threat of disease, an environmental factor associated with program timing); (3) issues of site implementation; (4) public health benefits; (5) record-keeping; (6) medical/emotional support. ResultsParticipants included 621 students and 579 parents; 566 student/parent dyads were included. Most respondents were female, felt it is important to be immunized against the flu, and received the influenza vaccine in the past. Fewer than 50% had received the intranasal vaccine. More parents (67%) than students (46%) expressed a general willingness to consent to utilizing a SLIP. The programmatic factors associated with public health were second only to safety/trust factors as the most important to parents and students when considering participation in a SLIP. Demographic variables were found to be associated with the importance ratings of program factors associated with participation in a SLIP. ConclusionsWhen considering possible participation in SLIPs, parents and students consider programmatic factors associated with safety/trust and public health benefits to be of the greatest importance. Further study will be needed to develop effective and culturally sensitive messaging that targets and emphasizes these factors to potentially increase participation in SLIPS.

PIN30 Economic Evaluation of a Cluster Randomized Controlled Trial of an Influenza Immunization Program Directed at Healthy Children

PIN30 Economic Evaluation of a Cluster Randomized Controlled Trial of an Influenza Immunization Program Directed at Healthy Children

Low Rates of Influenza Immunization in Young Children Under Ontario's Universal Influenza Immunization Program

Low Rates of Influenza Immunization in Young Children Under Ontario's Universal Influenza Immunization Program

The proportion of influenza vaccination in Ontario, Canada in 2007/2008 compared with other provinces

In 2000, Ontario, Canada introduced a universal influenza immunization program (UIIP) to provide free vaccines to its residents, whose ages are six months or older. The current study sought to measure the effect of the UIIP on influenza vaccination uptake in Ontario compared with other provinces combined. Data from the 2007/2008 Canadian Community Health Survey (cycle 4.1) were used in the analyses. Logistic regression analyses were conducted to estimate the odds ratios for influenza vaccination 2007/2008 associated with province of residence (Ontario versus other provinces combined) and other factors including chronic disease status, age, gender, household income, smoking status, having a medical doctor, and self-perceived health status. Living in Ontario was positively associated with having an influenza vaccine during the 2007/2008 season [odds ratio (OR) 1.50, 95% confidence interval (CI) 1.45-1.55]. Increased age (OR 6.13, 95% CI 5.77-6.51), a positive chronic disease status (OR 1.70, 95% CI 1.63-1.77) and having a regular medical doctor (OR 1.95, 95% CI 1.85-2.07) also demonstrated a positive relationship with influenza vaccination in 2007/2008. A stratified analysis by province of residence suggested that having a chronic disease, old age and high income had less impact on the likelihood of receiving a vaccine in Ontario than other provinces. The results of this study may help to inform the development of strategies to increase vaccination coverage in Canada.

Estimation of the Health Impact and Cost-Effectiveness of Influenza Vaccination with Enhanced Effectiveness in Canada

IntroductionThe propensity for influenza viruses to mutate and recombine makes them both a familiar threat and a prototype emerging infectious disease. Emerging evidence suggests that the use of MF59-adjuvanted vaccines in older adults and young children enhances protection against influenza infection and reduces adverse influenza-attributable outcomes compared to unadjuvanted vaccines. The health and economic impact of such vaccines in the Canadian population are uncertain.MethodsWe constructed an age-structured compartmental model simulating the transmission of influenza in the Canadian population over a ten-year period. We compared projected health outcomes (quality-adjusted life years (QALY) lost), costs, and incremental cost-effectiveness ratios (ICERs) for three strategies: (i) current use of unadjuvanted trivalent influenza vaccine; (ii) use of MF59-adjuvanted influenza vaccine adults ≥65 in the Canadian population, and (iii) adjuvanted vaccine used in both older adults and children aged < 6.ResultsIn the base case analysis, use of adjuvanted vaccine in older adults was highly cost-effective (ICER = $2111/QALY gained), but such a program was “dominated” by a program that extended the use of adjuvanted vaccine to include young children (ICER = $1612/QALY). Results were similar whether or not a universal influenza immunization program was used in other age groups; projections were robust in the face of wide-ranging sensitivity analyses.InterpretationBased on the best available data, it is projected that replacement of traditional trivalent influenza vaccines with MF59-adjuvanted vaccines would confer substantial benefits to vaccinated and unvaccinated individuals, and would be economically attractive relative to other widely-used preventive interventions.

H1N1 and Seasonal Influenza Vaccine Safety in the Vaccine Safety Datalink Project

The emergence of pandemic H1N1 influenza virus in early 2009 prompted the rapid licensure and use of H1N1 monovalent inactivated (MIV) and live, attenuated (LAMV) vaccines separate from seasonal trivalent inactivated (TIV) and live, attenuated (LAIV) influenza vaccines. A robust influenza immunization program in the U.S. requires ongoing monitoring of potential adverse events associated with vaccination. To prospectively conduct safety monitoring of H1N1 and seasonal influenza vaccines during the 2009-2010 season. The Vaccine Safety Datalink (VSD) Project monitors ∼9.2 million members in eight U.S. medical care organizations. Electronic data on vaccines and pre-specified adverse events were updated and analyzed weekly for signal detection from November 2009 to April 2010 using either a self-controlled design or a current versus historical comparison. Statistical signals were further evaluated using alternative approaches to identify temporal clusters and to control for time-varying confounders. As of May 1, 2010, a total of 1,345,663 MIV, 267,715 LAMV, 2,741,150 TIV, and 157,838 LAIV doses were administered in VSD. No significant associations were noted during sequential analyses for Guillain-Barré syndrome, most other neurologic outcomes, and allergic and cardiac events. For MIV, a statistical signal was observed for Bell's palsy for adults aged ≥25 years on March 31, 2010, using the self-controlled approach. Subsequent analyses revealed no significant temporal cluster. Case-centered logistic regression adjusting for seasonality demonstrated an OR for Bell's palsy of 1.26 (95% CI=0.97, 1.63). No major safety problems following H1N1 or seasonal influenza vaccines were detected in the 2009-2010 season in weekly sequential analyses. Seasonality likely contributed to the Bell's palsy signal following MIV. Prospective safety monitoring followed by rigorous signal refinement is critical to inform decision-making by regulatory and public health agencies.