Influenza Vaccination Coverage Rates in 5 European Countries: a Population-Based Cross-Sectional Analysis of the Seasons 02/03, 03/04 and 04/05

Influenza Vaccination Coverage among People with Self-Reported Cardiovascular Diseases-Findings from the Hungarian Implementation of the European Health Interview Survey

Worldwide, cardiovascular diseases are the leading cause of mortality. This has significant implications for public health. Influenza, a common infectious disease, poses an increased risk for individuals with chronic conditions, such as cardiovascular diseases. However, little is known about influenza vaccination coverage in this group. This study utilized data from the Hungarian implementation of the European Health Interview Survey to assess influenza vaccination coverage and its determinants among cardiovascular respondents from 2009 to 2019. The findings reveal a downward trend in the vaccination rates over the years (from 24% to 21%), despite the availability of free vaccination in Hungary for this high-risk population. The main factors influencing low influenza vaccine uptake were identified, as follows: young age, a lower level of education, good self-perceived health status, smoking, a lower frequency of medical visits, and not suffering from respiratory diseases. Addressing these disparities necessitates targeted vaccination strategies supported by enhanced education, better access to healthcare services, and the promotion of preventive healthcare measures. Improving vaccination coverage among patients with cardiovascular diseases is imperative for reducing influenza-related morbidity and mortality. This highlights the importance of comprehensive public health interventions and healthcare provider engagement in promoting vaccination among groups at increased risk.

Secular trends and determinants of influenza vaccination uptake among patients with cardiovascular disease in Korea: Analysis using a nationwide database

Background

Influenza vaccination reduces cardiovascular events in patients with cardiovascular disease (CVD). Identifying the factors that affect influenza vaccination uptake can help improve the prognosis in patients with CVD. This study aimed to evaluate the secular trends of influenza vaccination uptake and factors associated with lack of vaccination in individuals with CVD.

Materials and methods

We analyzed the annual trends and factors associated with influenza vaccination among 3,264 patients with CVD, included from the Korea National Health and Nutrition Examination Survey which reflect the health and nutritional status of the nationwide population of Korea conducted between 2007/2008 and 2018/2019. We used a stratified, multistage sampling method.

Results

The influenza vaccination rate was greater in patients with CVD (53–74%) than in those without CVD (28–40%). Multivariable logistic regression analysis showed that age <50 years [odds ratio (OR), 16.22; 95% confidence interval (CI), 7.72–34.07], 50–64 years (OR, 6.71; 95% CI, 4.37–10.28), male sex (OR, 1.45; 95% CI, 1.14–1.65), and asthma (OR, 0.45; 95% CI, 0.22–0.92) were independently associated with a lack of influenza vaccination. Among patients aged <65 years, smoking (OR, 2.30; 95% CI, 1.31–4.04), college graduation status (OR, 1.81; 95% CI, 1.16–2.82), and hypertension (OR, 0.70; 95% CI, 0.51–0.95) were independently associated with influenza vaccination. For individuals aged 65years, there was no significant determinant of lack of vaccination.

Conclusion

In patients with CVD, a continuous increase in the secular trend of influenza vaccination was demonstrated in Korea. Young age, male sex, and non-asthma status were independently associated with lack of influenza vaccination uptake.

How are reasons for encounter associated with influenza-like illness and acute respiratory infection diagnoses and interventions? A cohort study in eight Italian general practice populations

Background

Influenza-like illness (ILI) and Acute Respiratory Infections (ARI) are a considerable health problem in Europe. Most diagnoses are made by family physicians (FPs) and based on symptoms and clinical signs rather than on diagnostic testing. The International Classification of Primary Care (ICPC) advocates that FPs record patients’ ‘Reasons for Encounters’ (RfEs) as they are presented to them.

This study analyses the association of patients’ RfEs with FPs’ diagnoses of ILI and ARI diagnoses and FPs’ management of those patients.

Methods

Cohort study of practice populations. Over a 4-month period during the winter season 2013–14, eight FPs recorded ILI and ARI patients’ RfEs and how they were managed. FPs recorded details of their patients using the ICPC format, collecting data in an Episode of Care (EoC) structure.

Results

There were 688 patients diagnosed as having ILI; between them they presented with a total of 2,153 RfEs, most commonly fever (79.7%), cough (59.7%) and pain (33.0%).

The 848 patients with ARI presented with a total of 1,647 RfEs, most commonly cough (50.4%), throat symptoms (25.9%) and fever (19.9%). For patients with ILI, 37.0% of actions were related to medication for respiratory symptoms; this figure was 38.4% for patients with ARI. FPs referred six patients to specialists or hospitals (0.39% of all patients diagnosed with ILI and ARI).

Conclusions

In this study of patients with ILI and ARI, less than half received a prescription from their FPs, and the illnesses were mainly managed in primary care, with few patients’ needing referral. The ICPC classification allowed a standardised data collection system, providing documentary evidence of the management of those diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12875-021-01519-4.

Barriers Associated with the Uptake Ratio of Seasonal Flu Vaccine and Ways to Improve Influenza Vaccination Coverage among Young Health Care Workers in Poland

Despite not being full-time health care workers, annual flu vaccination is nevertheless an important consideration for medical students. This study examined the reasons for refusing flu vaccination among medical students, a group characterized by low vaccination coverage, despite the fact that the flu vaccine is arguably the most effective way of preventing serious flu complications. A cross-sectional survey was performed of 1313 students at the Medical University of Lodz. The findings indicate that the main sites of vaccination were primary care centers, and main source of information about influenza vaccination (about 90% of cases) was the general practitioner (GP). The most common motivations for vaccination were a recommendation by the family doctor or the belief that it was an important factor for protection against influenza. Most students reported various adverse effects after vaccination, usually mild pain at the site of vaccination, malaise, or fever. The main reasons for rejecting influenza vaccination were the apparent low risk of disease, the need for annual vaccination, the need to pay for it, lack of time or opportunity, lack of vaccination promotion, negative attitudes toward the flu vaccine, or the belief that there are other methods of preventing flu. To increase long-term vaccine acceptance and increase the vaccination rate among medical students and qualified health care workers, there is a need to adapt the health system and to initiate ongoing promotion programs at university to raise consciousness, promote vaccinations, and develop clinical skills for immunization.

Influenza Vaccination and Myo-Pericarditis in Patients Receiving Immune Checkpoint Inhibitors: Investigating the Likelihood of Interaction through the Vaccine Adverse Event Reporting System and VigiBase

Background: Evidence on whether the influenza vaccine could exacerbate immune-related adverse events, including myopericarditis (MP), in patients treated with immune checkpoint inhibitors (ICIs), is still conflicting. We explored this issue through a global real-world approach. Methods: We queried the Vaccine Adverse Event Reporting System (VAERS) and VigiBase to retrieve cases of MP in which the influenza vaccine and ICIs were recorded as suspect and were concomitantly reported. For the included cases, causality assessment and Drug Interaction Probability Scale (DIPS) algorithms were applied. Results: There were 191 and 399 reports of MP with the influenza vaccine that were retrieved (VAERS and VigiBase, respectively). No case of MP reporting the concomitant use of ICIs and the influenza vaccine was found in VAERS, while three cases of myocarditis were retrieved in VigiBase. All of the cases were unclassifiable for a causality assessment because of the lack of data concerning latency. According to the DIPS, one report was categorized as possible and two as doubtful. Conclusion: The paucity of cases coupled with the doubtful causality assessment make the potential interaction between influenza vaccines and ICIs in cancer patients negligible from clinical and epidemiological standpoints. These findings support the cardiovascular safety of the influenza vaccination, which remains strongly recommended in cancer patients, especially in the current COVID-19 era.

Understanding influenza vaccination among Portuguese elderly: the social ecological framework

This study intended to identify and quantify the social ecological model (SEM) levels associated to seasonal IV uptake in the Portuguese elderly population. Data from the 2014 National Health Survey was restricted to individuals aged 65+ years (n = 5669). Twenty-three independent variables were allocated to the SEM levels: individual, interpersonal, organizational, community and policy. Sex stratified and age adjusted analysis using Poisson regression were performed for each level and for a fitted full model. Relative reduction in pseudo R magnitude measured marginal contribution of each level. For men and women, older groups (85+ vs. 65–69; men, PR = 1.59 and women, PR = 1.56); having 3+ chronic conditions (men, PR = 1.39 and women, PR = 1.35); previous 4 weeks GP and outpatient visits were associated to higher IV uptake. For men, only 2 SEM levels were associated (individual and organizational) while for women the community level was also relevant. Main marginal contribution came from individual (17.9% and 16.3%) and organizational (30.7% and 22.7%) levels. This study highlights the importance of individual characteristics, access and use of health care services for the IV uptake and the sex differential behaviour.

Parental Perception Towards Flu Vaccination for Asthmatic Children in Saudi Arabia

Background 

Asthma is a major noncommunicable disease that affects around 235 million people, including children, globally. In the Kingdom of Saudi Arabia (KSA), the incidence of childhood asthma continues to increase. The Ministry of Health in Saudi Arabia has attempted to put policies in place to prevent the occurrence of asthma-related complications by encouraging parents to vaccinate their diagnosed asthmatic children with the flu vaccine. To date, however, there have been no studies investigating the use of flu vaccine among asthmatic children in KSA. Our research aims to explore the perception of parents with asthmatic children towards flu vaccination and its effect on the decision to vaccinate their children.

Methods

Our research was a cross-sectional study of 190 parents who presented with asthmatic children at King Fahad Medical City (KFMC) in Riyadh, KSA from October 2016 to April 2017. The study tools included structured and semi-structured questionnaires with demographic information, types of healthcare, and perceptions of parents towards flu vaccination. Data analysis was done using Statistical Package for the Social Sciences (SPSS; IBM, Armonk, NY).

Results

Samples were mostly Saudis (97%), who were married (92%), and in the age group of 21-40 years (70%). Most of them were females (59%). More than two-thirds of the parents had a middle school education or bachelor's degree, and more than half were employed. Parents with higher education had a higher rate of vaccination for their children, and they were more likely to believe that a non-vaccinated child is more likely to get flu. Almost 76% of parents with vaccinated children agreed that the flu vaccine could safeguard children against flu. Doctors' opinion about flu vaccination was significantly associated with the parents' decision. The multivariate regression analysis results showed that easy access to services and parents’ beliefs regarding vaccination are positively associated with influenza vaccination status.

Conclusion

Among the essential factors positively associated with the influenza vaccination status were a perception of easy access to vaccination services and the belief that non-vaccinated children are more likely to contract the flu virus. In contrast, the belief that vaccination prevents infection by the flu virus was negatively associated with vaccine uptake.

Risk Factors for Influenza Virus Related Severe Lower Respiratory Tract Infection in Children

BACKGROUND

Influenza virus is one of the most common respiratory pathogens for all age groups and may cause seasonal outbreaks. Our aim was to identify risk groups and factors associated with severe clinical course including mortality in children with influenza-related lower respiratory tract infection (LRTI).

METHODS

We conducted a retrospective study in children hospitalized with influenza virus LRTI from 2008 to 2018. Data on demographic features, influenza type, viral coinfection, primary and secondary bacterial infections (SBIs), time of onset of antiviral treatment, comorbidities, hospitalization length, pediatric intensive care unit admission/invasive mechanical ventilation (IMV) need and mortality were collected from medical records.

RESULTS

There were 280 patients hospitalized with LRTI and median hospitalization length was 9 days. Congenital heart disease, neuromuscular disease, SBIs and late-onset antiviral treatment were independent risk factors for prolonged hospital stay (P < 0.05). Pediatric intensive care unit admission was present in 20.4% (57) of the patients and 17.1% (48) of all patients required IMV. SBIs, lymphopenia, neutrophilia, immunosuppression and human bocavirus coinfection were independent risk factors for IMV support (P < 0.05). Eighteen patients died and immunosuppression, lymphopenia and SBIs were independent risk factors for mortality (P < 0.05).

CONCLUSIONS

Presence of comorbidity, SBIs, neutrophilia and lymphopenia at admission identified as risk factors for severe influenza infections including need for IMV and death. Although several studies showed that antiviral treatment reduce hospitalization, complications and mortality, there is a lack of prospective trials and patients for antiviral therapy should be carefully chosen by the clinician.

Physicians' awareness and practice toward influenza and pneumococcal vaccines for high-risk patients

Objectives:

The aim of the study is to assess the awareness of family medicine residents about influenza and pneumococcal vaccination for high-risk patients and to verify the most significant variables that might affect residents’ knowledge and the tools needed to enhance their practice.

Materials and Methods:

This cross-sectional study was conducted at four major hospitals in Riyadh, Saudi Arabia, during the period, October through December 2017. A pretested self-administered questionnaire was handed to 180 family residents. Descriptive statistics were used to analyze the study data. The Chi-square test was used to compare categorical variables data. The One-way ANOVA test was used to detect the significant difference.

Results:

The overall knowledge of physicians about influenza and pneumococcal vaccines was inadequate and was more toward pneumococcal vaccine, in spite their respectable knowledge about the target population. The main reasons for non- prescribing of vaccines were forgetfulness (59.4%), the availability of vaccines (33.9%), and the patients’ refusal (23.3%). The tools that might help for prescribing were the need for the presence of electronic reminder (69.4%) and the patients should follow a regular family physician (47.2%).

Conclusion:

Knowledge and practice of influenza and pneumococcal vaccination are inadequate. This is mainly because of forgetfulness owing to minimal guideline awareness, lack of vaccine availability, and patients’ refusal. The important recommendations to enhance vaccination practice among physicians are the implementation of electronic reminders, regular follow-up with the same physician in addition to educational programs during residency, and patient education about the importance of vaccinations as a means of disease prevention.

Predictors of yearly influenza vaccination in hospitalized and community based patients

Background

Understanding positive and negative influences on adult immunization status can help healthcare providers to better identify and target patients who are likely to need immunization. Our aim was to assess and compare influenza and pneumococcal (IV/PV) immunisation rates to identify vaccination predictors in Malta.

Method

One group consisted of all medical patients discharged from Mater Dei Hospital (MDH) over a one week period in February 2013. Patients were administered a phone questionnaire. A second group of patients receiving community-based care at local health centres over a one week period in March 2013 were interviewed, identifying vaccination eligibility as per 2010 WHO recommendations.

Results

A total of 150 community (Mean age 61.5 SD 15.8, Male 60%) and 149 hospitalised (Mean age 66.8, SD 13.6%, Male 48.3%) patients in whom influenza vaccine was indicated were recruited. In the current year, 44 and 48.3% received the seasonal influenza vaccine, while 32.0, and 49% vaccinated yearly respectively. Pneumococcal vaccination advice was less than 5% in both groups. On stepwise binary regression, vaccination predictors for the current year were regular yearly influenza vaccination (OR 93.62, CI: 31.8-275.5, p < 0.001) and vaccination reminders (OR 27.5, CI: 9.63-78.31, p < 0.001). Nursing home residence (OR 5.78, CI: 1.22-27.4,p = 0.011), congestive cardiac failure (OR 2.11, CI: 1.1-4.08, p = 0.02) and diabetes mellitus (OR 1.68, CI: 1.04-2.72, p = 0.034) were all predictors for vaccination on exclusion of the strongest two predictors. For successive yearly vaccination, influenza vaccine recommendation by healthcare professionals (OR 12.35, CI: 4.5-33.91, p < 0.001) and vaccination reminders (OR 5.99, CI: 3.13-11.45, p < 0.01) were main predictors. Congestive cardiac failure (OR 2.37, CI: 1.20-4.7, p = 0.13) and nursing home residence (OR 7.07, CI: 1.45-34.5, p = 0,005) were also positive predictors. Male gender was a negative predictor (OR 0.51, CI: 0.31-0.83, p = 0.006). Some of those who did not vaccinate were unaware of such need (40.5% of community and 15.6% of hospitalised patients).

Conclusions

Just under half of the patient population received the IV during 2012-2013 period. Hospitalized patients are more likely to vaccinate regularly while a large proportion of community patients are unaware of the indication to vaccinate.

Influenza Vaccination Rate and Reasons for Nonvaccination in Children With Cardiac Disease

BACKGROUND

Influenza is a major cause of respiratory morbidity worldwide. It poses a risk of complications in children with cardiac disease. Influenza vaccine is considered the most effective and safe means of preventing the disease. The aims of this study were to determine the rate of influenza vaccination in children with cardiac disease and to identify the reasons for failure to vaccinate in this patient population.

METHODS

The study group included 186 children and their parents who attended the cardiology institute of a tertiary pediatric medical center between September and October 2012. Parents were asked to complete a questionnaire covering demographics, clinical features, influenza vaccination, receipt of advice from medical professionals regarding vaccination and personal knowledge about and attitude toward the influenza vaccine.

RESULTS

Median age of the children was 7.6 years. Thirty-six percent had been vaccinated in the previous influenza season. Vaccination was unrelated to the child's age or sex or the parents' education. Factors significantly affecting the decision of the parents to have their child vaccinated were their knowledge, beliefs and conceptions about the vaccine and their receipt of a recommendation to do so from the pediatrician or cardiologist (P < 0.001).

CONCLUSIONS

The rate of vaccination against influenza is low in children with heart disease. Major factors encouraging vaccination are proper parental knowledge and the recommendation of the primary physician or cardiologist. Medical professionals caring for this patient population should be alerted to the need to routinely counsel parents on the importance of influenza vaccination.

The benefit of the doubt or doubts over benefits? A systematic literature review of perceived risks of vaccines in European populations

OBJECTIVES

The success of vaccination strategies depends in part on population perceptions of benefits and risks of vaccines and related confidence in vaccination. Better knowledge of public concerns about vaccines and what is driving them is needed to inform vaccination strategies and communications. This literature reviewer examined studies on vaccine and vaccination risk perceptions and concerns across European populations.

METHODS

A systematic literature review was conducted to identify studies published between 2004 and 2014 in Europe. A descriptive analysis was performed.

FINDINGS

A total of 145 articles were selected, most of which were conducted in the UK, the Netherlands and France and studied seasonal influenza, HPV and pandemic influenza vaccination. Across all countries and vaccines, the primary area of concern was vaccine safety, followed by perceptions of low likelihood of contracting vaccine-preventable diseases (VPDs), perceived low severity of VPDs, beliefs that vaccines do not work, and overall lack of information. Concerns were found to be vaccine-, country- and population-specific.

CONCLUSION

In addition to identifying concerns about vaccination in Europe, this study confirmed the notion that individuals have many safety concerns about vaccination and often believe that the risks of vaccination outweigh their benefits. More research needs to be conducted to explore the impact of different types of communication strategies, which would frame the benefits of vaccination as well as risks of not vaccinating. Strategies to better inform public perceptions of vaccines should include the provision of unbiased, comprehensive information tailored to population information needs, and delivered using multiple and new communication technologies such as social media.

ADHERENCE TO INFLUENZA VACCINATION AMONG MEDICAL STUDENTS DURING AND AFTER INFLUENZA A (H1N1) PANDEMIC

This study evaluated the adherence to influenza vaccination among medical students in 2010 and 2011. From August to December 2011, a questionnaire was used to record the influenza vaccination in 2010 and 2011, reasons for acceptance of the influenza vaccine and knowledge of healthcare workers about the influenza vaccine recommendation. One hundred and forty-four students from the 2ndto the 6th years of the medical school were interviewed. A great adherence to pandemic influenza vaccine was noted in 2010, (91% of the students), with "self-protection" being the most common reason cited for vaccination. Other determinants for the vaccination during pandemic were "convenient access to vaccine" and "encouragement by peers and teachers in workplaces and at the university". However, there was a great decay in the acceptance to vaccine in the next influenza season (2011). Only 42% of the students received the vaccine. They claimed "lack of time" and "have forgotten to take the vaccine" as the main reasons. The "knowledge on the recommendation of influenza vaccine to healthcare workers" increased when the students come to attend the last year of the medical school, but that was an insufficient motivator for vaccination. Strategies to increase vaccination should be based on the abovementioned aspects for the adoption of effective measures in both, pandemic and seasonal periods.

Factors effecting influenza vaccination uptake among health care workers: a multi-center cross-sectional study

BACKGROUND

The present study aimed to identify factors affecting vaccination against influenza among health professionals.

METHODS

We used a multi-centre cross-sectional design to conduct an online self-administered questionnaire with physicians and nurses at state and foundation university hospitals in the south-east of Turkey, between 1 January 2015 and 1 February 2015. The five participating hospitals provided staff email address lists filtered for physicians and nurses. The questionnaire comprised multiple choice questions covering demographic data, knowledge sources, and Likert-type items on factors affecting vaccination against influenza. The target response rate was 20 %.

RESULTS

In total, 642 (22 %) of 2870 health professionals (1220 physicians and 1650 nurses) responded to the questionnaire. Participants' mean age was 29.6 ± 9.2 years (range 17-62 years); 177 (28.2 %) were physicians and 448 (71.3 %) were nurses. The rate of regular vaccination was 9.2 % (15.2 % for physicians and 8.2 % for nurses). Increasing age, longer work duration in health services, being male, being a physician, working in an internal medicine department, having a chronic disease, and living with a person over 65 years old significantly increased vaccination compliance (p < 0.05). We found differences between vaccine compliant and non-compliant groups for expected benefit from vaccination, social influences, and personal efficacy (p < 0.05). Univariate analysis showed differences between the groups in perceptions of personal risks, side effects, and efficacy of the vaccine (p < 0.05). Multivariate analysis found that important factors influencing vaccination behavior were work place, colleagues' opinions, having a chronic disease, belief that vaccination was effective, and belief that flu can be prevented by natural ways.

CONCLUSION

Numerous factors influence health professionals' decisions about influenza vaccination. Strategies to increase the ratio of vaccination among physicians and nurses should consider all of these factors to increase the likelihood of success.

Household characteristics and influenza vaccination uptake in the community-dwelling elderly: a cross-sectional study

Elderly people are at higher risk of influenza diseases. The morbidity benefit of vaccination is often offset by its low and variable coverage in elderly people in the community.

To assess household and individual factors associated with influenza vaccination uptake in the community-dwelling elderly of age ≥ 65, data from a cross-sectional Thematic Household Survey conducted in 2011/12 in Hong Kong were analysed, using vaccination in the past 12 months as the outcome variable. Households comprising an elderly person living with non-elderly member(s) of age ≤ 64 were also evaluated. Data fields included socio-demographics, household structures, health status, eligibility to financial subsidy, and subscription to health insurance.

The influenza vaccination rate was 27% in 4204 elderly persons from 3224 households. Being male, being economically active, attaining primary education, having smoking behaviours were negatively associated with vaccination, while chronic illness and age ≥ 70 were positively associated factors. Elderly people living alone gave a variable rate of vaccination ranging from 16.4% in males of age 65–69 to 36.3% in females ≥ 70. Household size per se was not associated with vaccination, but a positive correlation could be seen if the household was composed of vaccinated non-elderly member(s).

Influenza vaccination uptake in the community-dwelling elderly is dependent on both individual and household characteristics, the latter including the influence of vaccinated non-elderly member(s). The low vaccination coverage of “younger” (age 65–69) elderly men living alone is particularly worrisome. Interventions focusing on vulnerable elderly people and their social networks would be desirable.

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Influenza vaccination coverage was < 30% in the community-dwelling elderly of age ≥ 65 in Hong Kong.

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Both individual and household factors were determinants of influenza vaccination in the elderly.

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Elderly men aged 65–69 living alone were particularly vulnerable to influenza.

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Elderly people living with vaccinated non-elderly member(s) gave a higher vaccination rate.

Interventions to increase influenza vaccination rates of those 60 years and older in the community

BACKGROUND

The effectiveness of interventions to increase the uptake of influenza vaccination in people aged 60 and older is uncertain.

OBJECTIVES

To assess access, provider, system and societal interventions to increase the uptake of influenza vaccination in people aged 60 years and older in the community.

SEARCH METHODS

We searched CENTRAL (2014, Issue 5), MEDLINE (January 1950 to May week 3 2014), EMBASE (1980 to June 2014), AgeLine (1978 to 4 June 2014), ERIC (1965 to June 2014) and CINAHL (1982 to June 2014).

SELECTION CRITERIA

Randomised controlled trials (RCTs) of interventions to increase influenza vaccination uptake in people aged 60 and older.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study quality and extracted influenza vaccine uptake data.

MAIN RESULTS

This update identified 13 new RCTs; the review now includes a total of 57 RCTs with 896,531 participants. The trials included community-dwelling seniors in high-income countries. Heterogeneity limited meta-analysis. The percentage of trials with low risk of bias for each domain was as follows: randomisation (33%); allocation concealment (11%); blinding (44%); missing data (49%) and selective reporting (100%). Increasing community demand (32 trials, 10 strategies)The interventions with a statistically significant result were: three trials (n = 64,200) of letter plus leaflet/postcard compared to letter (odds ratio (OR) 1.11, 95% confidence interval (CI) 1.07 to 1.15); two trials (n = 614) of nurses/pharmacists educating plus vaccinating patients (OR 3.29, 95% CI 1.91 to 5.66); single trials of a phone call from a senior (n = 193) (OR 3.33, 95% CI 1.79 to 6.22), a telephone invitation versus clinic drop-in (n = 243) (OR 2.72, 95% CI 1.55 to 4.76), a free groceries lottery (n = 291) (OR 1.04, 95% CI 0.62 to 1.76) and nurses educating and vaccinating patients (n = 485) (OR 152.95, 95% CI 9.39 to 2490.67).We did not pool the following trials due to considerable heterogeneity: postcard/letter/pamphlets (16 trials, n = 592,165); tailored communications (16 trials, n = 388,164); customised letter/phone-call (four trials, n = 82,465) and client-based appraisals (three trials, n = 4016), although several trials showed the interventions were effective. Enhancing vaccination access (10 trials, six strategies)The interventions with a statistically significant result were: two trials (n = 2112) of home visits compared to clinic invitation (OR 1.30, 95% CI 1.05 to 1.61); two trials (n = 2251) of free vaccine (OR 2.36, 95% CI 1.98 to 2.82) and one trial (n = 321) of patient group visits (OR 24.85, 95% CI 1.45 to 425.32). One trial (n = 350) of a home visit plus vaccine encouragement compared to a home visit plus safety advice was non-significant.We did not pool the following trials due to considerable heterogeneity: nurse home visits (two trials, n = 2069) and free vaccine compared to no intervention (two trials, n = 2250). Provider- or system-based interventions (17 trials, 11 strategies)The interventions with a statistically significant result were: two trials (n = 2815) of paying physicians (OR 2.22, 95% CI 1.77 to 2.77); one trial (n = 316) of reminding physicians about all their patients (OR 2.47, 95% CI 1.53 to 3.99); one trial (n = 8376) of posters plus postcards (OR 2.03, 95% CI 1.86 to 2.22); one trial (n = 1360) of chart review/feedback (OR 3.43, 95% CI 2.37 to 4.97) and one trial (n = 27,580) of educational outreach/feedback (OR 0.77, 95% CI 0.72 to 0.81).Trials of posters plus postcards versus posters (n = 5753), academic detailing (n = 1400) and increasing staff vaccination rates (n = 26,432) were non-significant.We did not pool the following trials due to considerable heterogeneity: reminding physicians (four trials, n = 202,264) and practice facilitators (three trials, n = 2183), although several trials showed the interventions were effective. Interventions at the societal level We identified no RCTs of interventions at the societal level.

AUTHORS' CONCLUSIONS

There are interventions that are effective for increasing community demand for vaccination, enhancing access and improving provider/system response. Heterogeneity limited pooling of trials.

Determinants of receiving the pandemic (H1N1) 2009 vaccine and intention to receive the seasonal influenza vaccine in Taiwan

OBJECTIVES

The paper examines the factors associated with both receiving pandemic (H1N1) 2009 vaccines and individuals' intentions to get the next seasonal influenza vaccine in Taiwan.

METHODS

We conducted a representative nationwide survey with in-person household interviews during April-July 2010. Multivariate logistic regression incorporated socio-demographic background, household characteristics, health status, behaviors, and perceptions of influenza and vaccination.

RESULTS

We completed interviews with 1,954 respondents. Among those, 548 (28.0%) received the pandemic (H1N1) 2009 vaccination, and 469 (24.0%) intended to get the next seasonal influenza vaccine. Receipt of the H1N1 vaccine was more prevalent among schoolchildren, the elderly, those who had contact with more people in their daily lives, and those who had received influenza vaccinations in previous years. In comparison, the intention to receive the next seasonal influenza vaccine tended to be stronger among children, the elderly, and those who reported less healthy status or lived with children, who received a seasonal influenza vaccination before, and who worried more about a possible new pandemic.

CONCLUSIONS

Children, the elderly, and those who had gotten seasonal flu shots before in Taiwan were more likely to both receive a pandemic H1N1 vaccination and intend to receive a seasonal influenza vaccine.

Seasonal influenza immunisation in Europe. Overview of recommendations and vaccination coverage for three seasons: pre-pandemic (2008/09), pandemic (2009/10) and post-pandemic (2010/11)

Since 2008, annual surveys of influenza vaccination policies, practices and coverage have been undertaken in 29 European Union (EU)/ European Economic Area (EEA) countries. After 2009, this monitored the impact of European Council recommendation to increase vaccination coverage to 75% among risk groups. This paper summarises the results of three seasonal influenza seasons: 2008/09, 2009/10 and 2010/11. In 2008/09, 27/29 countries completed the survey; in 2009/10 and 2010/11, 28/29 completed it. All or almost all countries recommended vaccination of older people (defined as those aged ≥50, ≥55, ≥59, ≥60 or ≥65 years), and people aged ≥6 months with clinical risk and healthcare workers. A total of 23 countries provided vaccination coverage data for older people, but only 7 and 10 had data for the clinical risk groups and healthcare workers, respectively. The number of countries recommending vaccination for some or all pregnant women increased from 10 in 2008/09 to 22 in 2010/11. Only three countries could report coverage among pregnant women. Seasonal influenza vaccination coverage during and after the pandemic season in older people and clinical groups remained unchanged in countries with higher coverage. However, small decreases were seen in most countries during this period. The results of the surveys indicate that most EU/EEA countries recommend influenza vaccination for the main target groups; however, only a few countries have achieved the target of 75% coverage among risk groups. Coverage among healthcare workers remained low.

Intanza (®) 9 µg intradermal seasonal influenza vaccine for adults 18 to 59 years of age

Seasonal influenza in healthy working-age adults accounts for a substantial part of the socioeconomic burden of this disease. Intanza® 9 µg (sanofi pasteur) is a microneedle-delivered intradermal trivalent inactivated influenza vaccine approved in 2009 for the prevention of seasonal influenza in adults 18 to 59 years of age. The microneedle system reliably and reproducibly delivers the vaccine to the dermis. Clinical studies show that Intanza 9 µg is as immunogenic and as well tolerated in working-age adults as a reference intramuscular trivalent inactivated vaccine. Local reactions to Intanza 9 µg, mainly erythema, are transient, mostly mild or moderate, and do not affect acceptability. Intanza 9 µg is considered satisfactory by at least 95% of both vaccinees and prescribers, especially because of the short needle and rapid administration. Because Intanza® 9 µg offers an alternative to intramuscular vaccines, it might help increase influenza vaccine coverage rates.

Effect of the conditional cash transfer program Oportunidades on vaccination coverage in older Mexican people

Background

Immunization is one of the most effective ways of preventing illness, disability and death from infectious diseases for older people. However, worldwide immunization rates are still low, particularly for the most vulnerable groups within the elderly population. The objective of this study was to estimate the effect of the Oportunidades -an incentive-based poverty alleviation program- on vaccination coverage for poor and rural older people in Mexico.

Methods

Cross-sectional study, based on 2007 Oportunidades Evaluation Survey, conducted in low-income households from 741 rural communities (localities with <2,500 inhabitants) of 13 Mexican states. Vaccination coverage was defined according to three individual vaccines: tetanus, influenza and pneumococcal, and for complete vaccination schedule. Propensity score matching and linear probability model were used in order to estimate the Oportunidades effect.

Results

12,146 older people were interviewed, and 7% presented cognitive impairment. Among remaining, 4,628 were matched. Low coverage rates were observed for the vaccines analyzed. For Oportunidades and non-Oportunidades populations were 46% and 41% for influenza, 52% and 45% for pneumococcal disease, and 79% and 71% for tetanus, respectively. Oportunidades effect was significant in increasing the proportion of older people vaccinated: for complete schedule 5.5% (CI_95% 2.8-8.3), for influenza 6.9% (CI_95% 3.8-9.6), for pneumococcal 7.2% (CI_95% 4.3-10.2), and for tetanus 6.6% (CI_95% 4.1-9.2).

Conclusions

The results of this study extend the evidence on the effect that conditional transfer programs exert on health indicators. In particular, Oportunidades increased vaccination rates in the population of older people. There is a need to continue raising vaccination rates, however, particularly for the most vulnerable older people.

Social determinants of health and seasonal influenza vaccination in adults ≥65 years: a systematic review of qualitative and quantitative data

BACKGROUND

Vaccination against influenza is considered the most important public health intervention to prevent unnecessary hospitalizations and premature deaths related to influenza in the elderly, though there are significant inequities among global influenza vaccine resources, capacities, and policies. The objective of this study was to assess the social determinants of health preventing adults ≥ 65 years old from accessing and accepting seasonal influenza vaccination.

METHODS

A systematic search was performed in January 2011 using MEDLINE, ISI - Web of Science, PsycINFO, and CINAHL (1980-2011). Reference lists of articles were also examined. Selection criteria included qualitative and quantitative studies written in English that examined social determinants of and barriers against seasonal influenza vaccination among adults ≥ 65 years. Two authors performed the quality assessment and data extraction. Thematic analysis was the main approach for joint synthesis, using identification and juxtaposition of themes associated with vaccination.

RESULTS

Overall, 58 studies were analyzed. Structural social determinants such as age, gender, marital status, education, ethnicity, socio-economic status, social and cultural values, as well as intermediary determinants including housing-place of residence, behavioral beliefs, social influences, previous vaccine experiences, perceived susceptibility, sources of information, and perceived health status influenced seasonal influenza vaccination. Healthcare system related factors including accessibility, affordability, knowledge and attitudes about vaccination, and physicians' advice were also important determinants of vaccination.

CONCLUSIONS

Our results demonstrate that the ability of adults ≥ 65 years to receive seasonal influenza vaccine is influenced by structural, intermediate, and healthcare-related social determinants which have an impact at the health system, provider, and individual levels.

Rates and Predictors for Influenza Vaccine Prescriptions Among HIV-infected Clinic Patients in Singapore

Introduction: Although Singapore national guidelines recommend influenza vaccination for individuals with comorbidities, the vaccine uptake remains relatively low. This study examines the rates of influenza vaccine prescriptions in a clinic population, and patient, doctor and clinic factors that could affect the vaccine prescribing rates. Materials and Methods: This retrospective review utilised electronic medical records from HIV-infected patients seen in an infectious disease (ID) specialist clinic. Data from 40 randomly selected patients per physician were analysed for the outcome of influenza vaccine prescriptions from 1 January to 31 December 2007. All 7 consultants and the 6 ID registrars who had spent at least 4 months in the Department during 2007 were included. Data analysed included patient, physician, and clinic characteristics, and clinically relevant outcomes of admission within a year, and the length of hospital stay. Results: Of the 461 HIV-infected patients analysed for this study, only 107 (23%) were prescribed influenza vaccine in 2007. Vaccine prescribing rates by individual physicians ranged from 0% to 77%. The outcome of vaccine prescribing was analysed by patient demographics (age >40 years, gender, race), physician characteristics (doctor grade, gender and training), and clinic volumes (number of patients per clinic session). Multivariate analysis demonstrated that patients with female doctors (OR 1.8, 95% CI, 1.1 to 3.0, P = 0.017), and doctors with overseas medical training (OR 11.6, 95% CI, 6.0 to 22.2, P <0.001) were significantly more likely to have influenza vaccine prescribed. On univariate analysis, patients were more likely to be admitted if they were male (OR 2.1, 95% CI, 1.0 to 5.1, P = 0.041), and over 40 years old (OR 2.1, 95% CI, 1.1 to 4.5, P = 0.024). Patients prescribed influenza vaccine showed a non-significant trend for protection against admission (OR 0.7, P = 0.288), and shorter length of stay (median 5 vs 9 days, P = 0.344). Conclusion: Influenza vaccine prescribing for HIV-infected outpatients in 2007 was only 23%, even in an ID specialist clinic. There was substantial variability in prescribing rates by individual physicians. Neither patient demographics nor patient volumes per clinic session had an impact on the prescribing rates, but significant predictors included physician gender and medical school training. Patients prescribed influenza vaccine had fewer admissions and shorter hospital lengths of stay, although these trends were non-significant. Key words: Asia, Influenza vaccine, HIV, Singapore, Vaccination rates

Outpatient-based pneumococcal vaccine campaign and survey of perceptions about pneumococcal vaccination in patients and doctors

PURPOSE

Despite the ready availability of pneumococcal vaccine, vaccination rates are quite low in South Korea. This study was designed to assess perceptions and awareness about pneumococcal vaccines among subjects at risk and find strategies to increases vaccine coverage rates.

MATERIALS AND METHODS

A cross sectional, community-based survey was conducted to assess perceptions about the pneumococcal vaccine at a local public health center. In a tertiary hospital, an outpatient- based pneumococcal vaccine campaign was carried out for the elderly and individuals with chronic co-morbidities from May to July of 2007.

RESULTS

Based on the survey, only 7.6% were ever informed about pneumococcal vaccination. The coverage rates of the pneumococcal vaccine before and after the hospital campaign showed an increased annual rate from 3.39% to 5.91%. The most common reason for vaccination was "doctor's advice" (53.3%). As for the reasons for not receiving vaccination, about 75% of high risk patients were not aware of the pneumococcal vaccine, which was the most important barrier to vaccination. Negative clinician's attitude was the second most common cause of non-vaccination.

CONCLUSION

Annual outpatient-based campaigns early in the influenza season may improve pneumococcal vaccine coverage rates. Doctor's advice was the most important encouraging factor for vaccination.

Head-to-head comparison of an intradermal and a virosome influenza vaccine in patients over the age of 60: evaluation of immunogenicity, cross-protection, safety and tolerability

In the present study we first compare immunogenicity against vaccine and heterologous circulating A(H1N1)pdm09 strains, tolerability and safety of intradermal Intanza 15 μg and of virosomal adjuvanted, intramuscularly delivered influenza vaccine, Inflexal V, in healthy elderly volunteers. Five-hundred participants were enrolled in the study and randomly assigned to the two vaccine groups to receive either one dose of Intanza 15 μg or Inflexal V vaccine. All subjects reported solicited local and systemic reactions occurred within 7 d after vaccination and unsolicited adverse events up to 21 d post-immunization and any serious adverse event appeared during the study. A subset of 55 participants was randomly selected for immunogenicity and cross-protection evaluations. Serum samples were collected before and 1 and 3 mo after immunization. Antibody responses were measured using hemagglutination inhibition (HI) against all viruses used in the study and neutralization (NT) assays against A(H1N1)pdm09 strains. At least one of the CHMP criteria for influenza vaccine approval in the elderly was met by virosomal vaccine against all the tested viruses; intradermal vaccine met all criteria against all strains. Several parameters of immune response against strains with a different antigenic pattern from that of vaccine A/California/04/09(H1N1)pdm09 were significantly higher in the intradermal vaccine group compared with the virosomal group. Safety and systemic tolerability of both vaccines were excellent, but injection site reactions occurred significantly more frequently in the intradermal vaccination group. Immunogenicity of Intanza 15 μg intradermal vaccine tended to be higher than that of Inflexal V against heterologous strains in healthy elderly.

Influenza vaccination coverage among patients and healthcare workers in a university hospital during the 2006-2007 influenza season

Despite years of public health effort to increase vaccine uptake among populations recommended for influenza vaccination, immunization rates remain low among patients and healthcare workers (HCWs). The objective of this study was to report on influenza vaccination coverage of patients and HCWs for the same time period in 4 wards of a university hospital. A prospective cross-sectional study was conducted among patients and HCWs between December 11, 2006 and April 15, 2007 and individual factors associated with being vaccinated against influenza were assessed. Results indicated that older patients were significantly more vaccinated than younger patients. Physicians and residents were more likely to be vaccinated that the rest of staff, with possible differences between wards. Immunization of HCWs is a major issue in infection control in hospitals and long-term care facilities. However, the impact of influenza vaccination among HCWs in reducing hospital-acquired influenza and patient morbidity needs to be explored further.

Current evidence on intradermal influenza vaccines administered by Soluvia™ licensed micro injection system

Among the several strategies explored for (1) the enhancement of the immune response to influenza immunization, (2) the improvement of the vaccine acceptability and (3) the overcoming of the egg-dependency for vaccine production, intradermal administration of influenza vaccine emerges as a promising alternative to conventional intramuscular route, thanks to the recent availability of new delivery devices and the perception of advantages in terms of immunogenicity, safety, reduction of antigen content and acceptability.

 

Data from clinical trials performed in children, adults <60 y and elderly people and post-marketing surveillance demonstrate that actually, licensed intradermal influenza vaccines, Intanza™ 9 and 15 µg and Fluzone™ Intradermal, administered by the microinjection system Soluvia™, show an excellent acceptability, tolerability and safety profile. Formulations containing 9 and 15 μg per strain demonstrate, respectively, comparable and superior immunogenicity than conventional intramuscular vaccines. Licensed intradermal influenza vaccines can be considered a valid alternative to standard intramuscular vaccination offering significant advantages in low-responder populations and helping to increase influenza vaccination coverage rates especially in people with fear of needles or high apprehension associated with annual vaccination.

Factors associated with uptake of seasonal and pandemic influenza vaccine among clinical risk groups in the UK: an analysis using the General Practice Research Database

BACKGROUND

Influenza vaccine uptake rates are low compared with uptake rates of many other vaccines. It is unclear how this differs between risk groups in the population and between pandemic and non-pandemic influenza vaccines.

AIM

This study sought to estimate uptake rates of pandemic and seasonal influenza vaccines among clinical risk groups in the UK during the 2009/2010 influenza season and to identify predictors of vaccine uptake in this cohort.

METHODS

Uptake rates were calculated using data from the UK General Practice Research Database (GPRD). Predictors of vaccination were identified using a modified Poisson regression with robust standard error estimates.

RESULTS

Uptake of pandemic influenza vaccine in clinical risk groups was 40.3% and uptake of seasonal influenza vaccine was 61.3%. Factors found to be predictive of seasonal and pandemic influenza vaccination included age and the total number of underlying health conditions an individual had. At risk individuals in those age groups in which universal vaccination of the general population was recommended were more likely to have been vaccinated than individuals in age groups in which only clinical risk groups were recommended for vaccination; hence children in clinical risk groups were more likely to receive pandemic than seasonal influenza vaccine. In older people, having a history of Guillain Barré syndrome was associated with a reduced likelihood of receipt of both seasonal (IRR(adj) 0.83, CI(95) 0.77-0.90) and pandemic influenza vaccines (IRR(adj) 0.82, CI(95) 0.73-0.92).

DISCUSSION

Uptake of pandemic influenza vaccine was lower than that of seasonal influenza vaccine among those at a clinically high risk of influenza related morbidity. This suggests that vaccination strategies may need to be altered during future pandemics. Recommending universal vaccination within age categories in which there is a large proportion of high risk individuals could be considered as this may result in higher uptake among clinical risk groups.

Influenza vaccination coverage among high-risk groups in 11 European countries

BACKGROUND

National vaccination coverage rates for individuals at increased risk of influenza-related complications represent a useful public health indicator of preparedness. We compared European countries regarding (i) vaccination coverage among high-risk groups and (ii) the likelihood that high-risk individuals reported influenza vaccination compared with those at lower risk.

METHODS

We used data from the Survey of Health, Ageing and Retirement in Europe (SHARE) collected in 2004-05. Adults aged ≥ 50 years from 11 countries provided self-reports of an influenza vaccination in the previous year (n = 16,913). We defined four high-risk groups (age ≥ 65 years, presence of vascular disease, chronic lung disease or diabetes) and calculated vaccination coverage with 95% confidence intervals for each country. Country-specific multivariable logistic regression was used to estimate odds ratios (ORs) for membership in a high-risk group and vaccination.

RESULTS

The Netherlands had the highest influenza vaccination coverage in high-risk groups (≥ 75% in any group) while Greece had the lowest (<27% in any group). Older age was positively associated with report of vaccination in all countries, but the strength of this association varied from an OR of <2 (Germany) to >13 (The Netherlands). The ORs for the chronic disease groups was ≥ 4 for The Netherlands and were considerably lower (and often not statistically significant) for the other countries.

CONCLUSION

Influenza vaccination coverage among high-risk groups varies considerably between European countries. Our findings highlight potential opportunities for reducing influenza-related complications through support for vaccination programs that target high-risk individuals more effectively.

Erratic flu vaccination emerges from short-sighted behavior in contact networks

The effectiveness of seasonal influenza vaccination programs depends on individual-level compliance. Perceptions about risks associated with infection and vaccination can strongly influence vaccination decisions and thus the ultimate course of an epidemic. Here we investigate the interplay between contact patterns, influenza-related behavior, and disease dynamics by incorporating game theory into network models. When individuals make decisions based on past epidemics, we find that individuals with many contacts vaccinate, whereas individuals with few contacts do not. However, the threshold number of contacts above which to vaccinate is highly dependent on the overall network structure of the population and has the potential to oscillate more wildly than has been observed empirically. When we increase the number of prior seasons that individuals recall when making vaccination decisions, behavior and thus disease dynamics become less variable. For some networks, we also find that higher flu transmission rates may, counterintuitively, lead to lower (vaccine-mediated) disease prevalence. Our work demonstrates that rich and complex dynamics can result from the interaction between infectious diseases, human contact patterns, and behavior.

The 2009 pandemic H1N1 influenza vaccination in France: who accepted to receive the vaccine and why?

Introduction: Previous studies investigating determinants of 2009 (H1N1) pandemic influenza vaccine acceptance have focused on target groups such as healthcare workers. Few studies in the European Union have examined the self-reported reasons as well as predictive socio-demographic and health factors for pandemic influenza vaccine acceptance in the general population, even though influenza vaccine was recommended for all people.

Methods: A nationwide telephone survey was conducted in France during the peak of the outbreak that occurred in December 2009 in adults (≥ 16 years), using a proportional random-digit dialing.

Results: Interviews were completed by 1003 individuals, of whom 275 (27.4%) either had received pandemic influenza vaccine during the last weeks or intended to get vaccinated in the next weeks. Acceptance rates of pandemic vaccine were significantly higher among men, more educated and wealthier people, as well as persons who had a prior experience of influenza vaccination. The patterns of self-reported reasons for vaccine acceptance could be broadly divided into 3 groups related to (1) the mental representation of the threat – in particular the beliefs associated with the severity and personal vulnerability to the illness, (2) the perception of efficacy and safety of the vaccine, and (3) trust/distrust toward those advocating the vaccine.

Conclusions: This national study indicates that social and cognitive determinants of pandemic influenza vaccine acceptance among French adults were relatively similar to those identified by previous studies of acceptance of seasonal influenza vaccine.

Absence of influenza vaccination among high-risk older adults in Taiwan

Background

Older adults, who often have more than one chronic disease, are at greater risk of influenza and its complications. However, because they often see physicians for other more pressing complaints, their physicians, focusing on one condition, may forget to suggest preventive measures for other diseases such as influenza. This study investigates what major factors affect an older adult with more than one chronic condition missing a vaccination opportunity.

Methods

Retrospectively reviewing a nationally representative random sample of medical claims from Taiwan's National Health Insurance Research Database during the period 2004 - 2006, we first identified patients sixty-five years or older who had visited physicians. Each patient was assigned a proxy for health status, the Charlson Comorbidity Index (CCI) score. An older claimant was defined has having "absence of a vaccination" when he or she had visited a physician during an influenza season but did not receive an influenza vaccination. Multivariate logistic regression was performed to estimate how likely it would be for older adults with various CCI scores to miss a vaccination.

Results

Out of 200,000 randomly selected claims, 20,923 older adults were included in our final analysis. We found older adults with higher CCIs to be more likely to have an absence of vaccination (p < 0.01). Our multivariate logistic regression results revealed CCI to be the greatest predictor of absence of vaccination, after controlling for individual factors and medical setting. Older adults with CCI scores three or higher were nearly five times more likely to miss a vaccination than those with a CCI of zero [OR: 4.93 (95%CI, 4.47-5.42)]. Those with CCIs of one and two were 2.53 and 3.92 times more likely to miss vaccination than those with a CCI of zero [OR 2.53 (95%CI, 2.26-2.84) and OR 3.92 (95%CI, 3.51-4.38), respectively].

Conclusions

The greater the number of certain comorbid conditions, the greater the likelihood a flu vaccination will be missed. Physicians would be well advised to not let the presenting problems of older patients distract from other possible health problems that might also need attention, in this case influenza vaccinations.

Interventions to increase influenza vaccination rates of those 60 years and older in the community

BACKGROUND

Although the evidence to support influenza vaccination is poor, it is promoted by many health authorities. There is uncertainty about the effectiveness of interventions to increase influenza vaccination rates in those 60 years or older.

OBJECTIVES

To assess effects of interventions to increase influenza vaccination rates in those 60 or older.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2010, issue 3), containing the Cochrane Acute Respiratory Infections Group's Specialized Register, MEDLINE (January 1950 to July 2010), PubMed (January 1950 to July 2010), EMBASE (1980 to 2010 Week 28), AgeLine (1978 to July 2010), ERIC (1965 to July 2010) and CINAHL (1982 to July 2010).

SELECTION CRITERIA

Randomized controlled trials (RCTs) to increase influenza vaccination rates in those aged 60 years and older, recording influenza vaccination status either through clinic records, billing data or local/national vaccination registers.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study quality and extracted data.

MAIN RESULTS

Forty-four RCTs were included. All included RCTs studied seniors in the community and in high-income countries. No RCTs of society-level interventions were included. Heterogeneity was marked and meta-analysis was limited. Only five RCTs were graded at low and six at moderate risk of bias. They included three of 13 personalized postcard interventions (all three with the 95% confidence interval (CI) above unity), two of the four home visit interventions (both with 95% CI above unity, but one a small study), three of the four reminder to physicians interventions (none with 95% CI above unity) and three of the four facilitator interventions (one with 95% CI above unity, and one P < 0.01). The other 33 RCTs were at high risk of bias and no recommendations for practice can be drawn.

AUTHORS' CONCLUSIONS

Personalized postcards or phone calls are effective, and home visits, and facilitators, may be effective. Reminders to physicians are not. There is insufficient good evidence for other interventions.

New interventions to increase influenza vaccination rates in health care workers

BACKGROUND

The most effective strategy for avoiding nosocomial influenza outbreaks is through vaccination of health care workers (HCWs). In Spain, HCW vaccination coverage rarely exceeds 25%. The objective of this study was to determine whether an active vaccination campaign promoting communication among HCWs increased influenza vaccination coverage rates and permitted a shorter campaign.

METHODS

This was a before-after trial, comparing free mobile vaccination teams without and with strategies promoting HCW involvement by means of weekly educational and promotional messages through electronic mail, including 2 prize draws for vaccinated HCWs and a Web page including pictures of vaccinated HCWs and all senior hospital management. Weekly coverages were publicized, the staff of mobile units was increased, and their routes in the hospital were advertised. The study population was >4500 HCWs (permanent and temporary staff) at a Spanish university hospital during the 2007-08 and 2008-09 influenza seasons.

RESULTS

Coverage was 23% (95% confidence interval [CI], 22.5%-24.9%) in the 2007-08 season and 37% (95% CI, 34.7%-37.4%) in 2008-09 season. The vaccination rate was highest in HCWs aged > or =65 years and in physicians. The weekly vaccination rates were significantly higher for the 2008-09 season compared with the 2007-08 season except for the first and third weeks; for example, in week 2, the rate was 1.7 HCWs per 100 persons-week (95% CI, 1.3-2.1) in 2007-08, compared with 3.7 HCWs per 100 persons-week (95% CI, 3.2-4.4) in 2009-09. Rate increases were concentrated in the first weeks of the program, with a peak occurring in week 3 during the 2007-08 season and in week 2 during the 2008-09 season.

CONCLUSION

This intervention improved influenza vaccination coverage of HCWs and allowed more rapid achievement of higher coverage.

Influenza vaccination and cardiovascular mortality in women and men at least 60 years of age in the metropolitan area of sao paulo, Brazil

OBJECTIVES

Influenza (flu) vaccination has been associated with a reduction in cardiovascular mortality in a metropolitan area of Brazil. Nevertheless, it is unknown whether sex influences this outcome. The aim of the study was analyze the cardiovascular disease (CVD) mortality in women and men before and after the initiation of a flu vaccination program.

METHODS

We analyzed the mortality of ischemic heart disease (IHD), stroke, and external causes (EC) in women and men at least 60 years of age in the metropolitan area of São Paulo before and after the initiation of a flu vaccination program. Estimates of the population were obtained from the Brazilian Institute of Geography and Statistics and the mortality data from the Ministry of Health for the period between 1980 and 2006. The risk of death was adjusted by the direct method using the 1960 world standard population.

RESULTS

Change in trend in mortality after vaccination was significant only for IHD (-9.3% vs -30.2%; P = .022) and remained unchanged for stroke (-31.4% vs -25.3%; P =.931) and EC (-8.5% vs -1.2%; P = .941). The decline in IHD pre- (1980-1995) and post-vaccination (1996-2006) was greater in women (-3.8% vs -28.8%; P = .001) than in men (-12.9% vs -30.4%; P = .054).

CONCLUSION

Flu vaccination was associated with a significant reduction of IHD mortality, more so in women than in men.

Determinants of influenza immunization uptake in Canadian youths

OBJECTIVE

To describe rate and determinants of influenza vaccination among Canadian youths.

METHODS

We conducted an analysis of cross-sectional data from the Canadian Community Health Survey (CCHS) cycle 3.1 collected by Statistics Canada in 2005. This is a population-based survey collecting information pertaining to the Canadian population health status, health care utilization and health determinants. The CCHS 3.1 included 12,170 respondents age 12-17 years old who answered questions pertaining to influenza vaccination. We used multivariate logistic regression to estimate the odds of having received the influenza vaccination in the last 12 months, adjusting for potential confounders.

RESULTS

Less than a quarter of Canadian youth reported receiving the influenza vaccination in the previous year. The most common reason for not getting the vaccination was "did not think it was necessary" (40.82%). Having chronic illness, and being an immigrant was significantly associated with a higher odds of receiving the influenza vaccination, while having an allergy and increasing frequency of alcohol drinking was associated with lower odds of receiving influenza vaccination. Smoking status acted as an effect modifier for many variables except for immigration status.

CONCLUSIONS

Influenza vaccination rate in Canadian youths is low. Judgement values on its necessity are a major factor in the decision to receive influenza vaccination. Strategies to involve youths in influenza vaccination programs and campaigns will be essential to achieve better national coverage.

2005 and 2006 seasonal influenza vaccination coverage rates in 10 countries in Africa, Asia Pacific, Europe, Latin America and the Middle East

Recommendations for seasonal influenza vaccination are standard in most developed countries. Many rapidly developing countries have recently begun to adopt recommendations for high-risk target groups, such as the elderly. Population-based surveys to determine use, rather than purchases, of seasonal influenza vaccine are rare outside North America and Western Europe. Such surveys can provide important information on the progress of national immunization programs and on the awareness of influenza among the general public. We report the results of a survey conducted in 10 countries in Africa, Asia Pacific, Eastern Europe, Latin America and the Middle East that aimed to determine influenza vaccination coverage among adults, the elderly, and children and to find out how influenza is perceived in these regions. Seasonal influenza vaccine coverage varied markedly across countries, and no single factor guaranteed high coverage. Our results indicate that strong recommendations appear insufficient, and that fully funded immunization programs together with high awareness in the population are key to encouraging high influenza vaccination coverage.

Willingness to vaccinate and to be vaccinated in adults

Vaccination may be mandated by regulation, as in some national infant vaccination programs, encouraged by health authorities, as in 'Flu vaccine campaigns for adults aged 60 years and older, or linked to the informed decision of individuals. Other methods include promotion by incentives to general practitioners, and recommendations from healthcare workers. All these factors contribute to variable vaccine coverage between countries and between different age and socio-economic groups. Many other factors, including providers' patient-oriented interventions and reimbursement issues play an important role in determining the level of vaccine uptake in a given population for a particular disease. However, the first step in vaccination campaigns is to give motivating information to healthcare workers that the benefits of being vaccinated outweigh possible inconvenience or adverse reactions. The information must be complete and accurate.When it has been ascertained that this information is understood and accepted, a system providing cheap and easy vaccination must be organised. Special groups such as the house-bound will need particular attention, appropriate information, and be included in free vaccination schemes. It should be acknowledged that social pressure often influences (positively or negatively) the decision of the individual. Lastly, a massive but objective information campaign is needed for the whole population, each and every visit to a health clinic being treated as an opportunity to check vaccination status and to vaccinate immediately if necessary. Simultaneous vaccination with two or more vaccines increases the chances of reaching the required population cover.

Influenza vaccination uptake and socioeconomic determinants in 11 European countries

BACKGROUND

The objective of this study was to assess the predictive effects of socioeconomic factors to explain influenza vaccination coverage rates in 11 European countries.

METHODS

Data from national household surveys collected over up to seven consecutive seasons between 2001/2002 and 2007/2008 were analyzed to assess the associations of socioeconomic factors with immunization against influenza.

RESULTS

In total, data from 92,101 household contacts representative for the national non-institutionalized population aged above 14 years were analyzed. Influenza vaccination coverage rates in Europe remain suboptimal with little or no progress in the last years. The results of this study indicate that gender, household income, size of household, educational level and population size of living residence may significantly contribute to explain chances of getting immunized against influenza apart from the known risk factors age and chronic illness. The effect of these socioeconomic factors was differently expressed among the countries and could not be explained solely on basis of economic characteristics of these countries.

CONCLUSIONS

Future measures should address inequalities to achieve the WHO target by 2010 with an influenza vaccination rate of 75% in the elderly. National vaccination campaigns may need to take socioeconomic segments of the population here identified as less likely of getting the influenza vaccine into account.

Intradermal influenza vaccination of healthy adults using a new microinjection system: a 3-year randomised controlled safety and immunogenicity trial

BACKGROUND

Intradermal vaccination provides direct and potentially more efficient access to the immune system via specialised dendritic cells and draining lymphatic vessels. We investigated the immunogenicity and safety during 3 successive years of different dosages of a trivalent, inactivated, split-virion vaccine against seasonal influenza given intradermally using a microinjection system compared with an intramuscular control vaccine.

METHODS

In a randomised, partially blinded, controlled study, healthy volunteers (1150 aged 18 to 57 years at enrollment) received three annual vaccinations of intradermal or intramuscular vaccine. In Year 1, subjects were randomised to one of three groups: 3 microg or 6 microg haemagglutinin/strain/dose of inactivated influenza vaccine intradermally, or a licensed inactivated influenza vaccine intramuscularly containing 15 microg/strain/dose. In Year 2 subjects were randomised again to one of two groups: 9 microg/strain/dose intradermally or 15 microg intramuscularly. In Year 3 subjects were randomised a third time to one of two groups: 9 microg intradermally or 15 microg intramuscularly. Randomisation lists in Year 1 were stratified for site. Randomisation lists in Years 2 and 3 were stratified for site and by vaccine received in previous years to ensure the inclusion of a comparable number of subjects in a vaccine group at each centre each year. Immunogenicity was assessed 21 days after each vaccination. Safety was assessed throughout the study.

RESULTS

In Years 2 and 3, 9 microg intradermal was comparably immunogenic to 15 microg intramuscular for all strains, and both vaccines met European requirements for annual licensing of influenza vaccines. The 3 microg and 6 microg intradermal formulations were less immunogenic than intramuscular 15 microg. Safety of the intradermal and intramuscular vaccinations was comparable in each year of the study. Injection site erythema and swelling was more common with the intradermal route.

CONCLUSION

An influenza vaccine with 9 microg of haemagglutinin/strain given using an intradermal microinjection system showed comparable immunogenic and safety profiles to a licensed intramuscular vaccine, and presents a promising alternative to intramuscular vaccination for influenza for adults younger than 60 years.

TRIAL REGISTRATION

(Clinicaltrials.gov) NCT00703651.

Influenza vaccination coverage rates in five European countries during season 2006/07 and trends over six consecutive seasons

BACKGROUND

The objectives of the survey were to identify the level of influenza vaccination coverage in five European countries between 2001 and 2007, to understand the drivers and barriers to vaccination, to assess vaccination intentions for the winter 2007/08 as well as major encouraging factors for vaccination.

METHODS

Between 2001 and 2007, representative household surveys were performed with telephone or mailed (France) interviews of individuals aged 14 and above. The questionnaire used in the UK, Germany, Italy, France and Spain was essentially the same in all seasons. The data were subsequently pooled. Four target groups were defined for the analysis: 1) persons aged 65 years and over; 2) persons working in the medical field; 3) chronically ill persons and 4) combined target group composed of individuals belonging to one or more of the previous groups 1, 2 or 3.

RESULTS

In 2006/07, vaccination coverage was, 25.0% in UK, 27.4% in Germany, 21.8% in Spain, 24.2% in France and 24.4% in Italy. During six influenza seasons (2001-2007), vaccination coverage showed a slight positive trend in the five countries (p < or = 0.0001). In the elderly (> or = 65 years), across all countries, no significant trend was seen; the vaccination rate decreased non-significantly from a peak of 64.2% in season 2005/06 to 61.1% in season 2006/07. The most frequent reason for getting vaccinated was a recommendation by the family doctor or nurse (51%), and this was also perceived as the major encouraging factor for vaccination (61%). The main reason for not getting vaccinated was feeling unlikely to catch the flu (36%).

CONCLUSION

In the UK, Germany and Spain, influenza vaccination coverage rates in season 2006/07 dropped slightly compared to the previous season. However, a trend of increasing vaccination coverage was observed from 2001/02 to 2006/07 across Europe. The family doctor is the major source of encouragement for individuals getting vaccinated. Efforts to overcome the barriers to vaccination need to be put in place to reach the WHO objective of 75% coverage in the elderly by 2010. This is a major challenge to be faced by governments, healthcare workers and healthcare organisations.