Influenza vaccination for healthcare workers who work with the elderly: Systematic review

Factors associated with repeated influenza vaccine uptake among aged care staff in an Australian sample from 2017 to 2019

BACKGROUND/AIM

Influenza vaccination is strongly recommended every year for aged care staff to protect themselves and minimise risk of transmission to residents. This study aimed to determine the factors associated with repeated annual influenza vaccine uptake among Australian aged care staff from 2017 to 2019.

METHODS

Demographic, medical and vaccination data collected from the staff, who participated in an observational study from nine aged care facilities under a single provider in Sydney Australia, were analysed retrospectively. Based on the pattern of repeated influenza vaccination from 2017 to 2019, three groups were identified: (1) unvaccinated all three years; (2) vaccinated occasionally(once or twice) over three years; and (3)vaccinated all threeyears. Multinomial logistic regression analysis was performed to better understand the factors associated with the pattern of repeated influenza vaccination.

RESULTS

From a total of 138 staff, between 2017 and 2019, 28.9 % (n = 40) never had a vaccination, while 44.2 % (n = 61) had vaccination occasionally and 26.8 % (n = 37) had vaccination all three years. In the multinomial logistic regression model, those who were<40 years old (OR = 0.57, 95 % CI: 0.19-0.90, p < 0.05) and those who were current smokers (OR = 0.20; 95 % CI: 0.03-0.76, p < 0.05) were less likely to have repeated vaccination for all three years compared to the unvaccinated group. Those who were<40 years old (OR = 0.61; 95 % CI: 0.22-0.68, p < 0.05) and those who were born overseas (OR = 0.50; 95 % CI:0.27-0.69, p < 0.05) were more likely to be vaccinated occasionally compared to the unvaccinated group.

CONCLUSION

The significant predictors of repeated vaccine uptake across the three-year study period among aged care staff were age, smoking status and country of birth (Other vs Australia). Targeted interventions towards the younger age group (<40 years old), smokers and those who were born overseas could improve repeated influenza vaccination uptake in the aged care workforce.

Vaccinating Front-Line Healthcare Workers: Results of a Pre-Pandemic Cross-Sectional Study from North-Eastern Italy on First Responders

First responders are front-line healthcare workers who are potentially exposed to different infectious agents. Characterizing their knowledge, attitudes, and practices (KAP) towards immunization, therefore, has the potential to significantly improve occupational health and safety. A cross-sectional study was performed in October 2018 using a sample of 161 first responders from the Parma Province (mean age 45.1 ± 14.1 years; seniority 10.8 ± 8.6 years). The participants were questioned on three recommended vaccinations (i.e., the seasonal influenza, measles, and pertussis vaccines) and on meningococcal vaccines (not officially recommended for first responders). The participant’s knowledge status and risk perception were assessed as percentage values through a specifically designed questionnaire. Adjusted odds ratios (aOR) for factors associated with vaccination status were calculated by means of a binary logistic regression analysis. The internal consistency result, calculated using a general knowledge test, was good (Cronbach’s alpha = 0.894), but the corresponding score was unsatisfying (46.5% ± 32.4), evidencing uncertainties surrounding the recommendations for measles and meningococcal vaccines (39.1% and 34.2% incorrect answers, respectively). While the large majority of respondents were favorable towards the meningococcal (89.4%), measles (87.5%), and pertussis vaccines (83.0%), 55.3% exhibited a favorable attitude toward the seasonal influenza vaccine, the uptake of which in 2018, was reported by 28.0% of respondents, compared to the self-reported lifetime status for meningitis (26.1%), measles (42.2%), and pertussis (34.8%). Not coincidentally, all assessed infections were associated with a low-risk perception score, particularly influenza (33.9% ± 18.4). Interestingly enough, neither knowledge status nor risk perception were associated with vaccination rates. More precisely, the main predictor for being vaccinated against seasonal influenza in 2018 was a seniority of ≥10 years (aOR 3.26, 95% confidence interval [95% CI] 1.35–7.91), while both pertussis and measles were positively associated with higher educational achievement (aOR 3.27, 95%CI 1.29–8.30; and aOR 2.69, 95%CI 1.09–6.65, respectively). The reasons for vaccination gaps among the sampled first responders, apparently, did not find their roots in inappropriate knowledge status and risk perception alone. However, the very low rates of sampled immunization lead us to recommend stronger and more appropriate information campaigns.

Adherence to Vaccination Policy among Public Health Professionals: Results of a National Survey in Italy

Starting from 2013, the number of unvaccinated people alarmingly increased in Italy; therefore, in 2017 a new Vaccine National Plan was approved. Healthcare workers (HCWs), especially public health professionals (PHPs, i.e., workers in in the sector of hygiene and preventive medicine), have an important role in informing and promoting vaccinations. In this context, the Italian Study Group of Hospital Hygiene of the Italian Society of Hygiene, Preventive Medicine and Public Health (GISIO-SItI) conducted a national survey to assess knowledge, attitude, and practices towards recommended vaccinations among PHPs. The survey was conducted during October 2019 with an anonymous questionnaire distributed to PHPs attending the 52° SItI National Congress. Overall, 57.1% of operators answered correctly to all seven recommended vaccinations, 12.8% reported to be vaccinated for all seven recommended vaccinations, while 30% were naturally immunized. A higher immunization coverage was reported for anti-hepatitis B (88.9%) and measles (86.1%), and 81.3% of the participants reported being offered the influenza vaccination during the 2018/2019 season. The majority of our sample indicated that hepatitis B (95%) and influenza (93.7%) were the recommended vaccines for HCWs, while less was known regarding varicella, pertussis, diphtheria, and tetanus boosters every 10 years. PHPs who were vaccinated (or who intended to be vaccinated) were more likely to recommend vaccinations to their patients and provided a reassuring example to those hesitant patients. Finally, this is the first study that identified good algorithms (using the techniques of machine learning as Random Forest and Deep Learning) to predict the knowledge of PHPs regarding recommended vaccinations with possible applications in other national and international contexts.

Knowledge, attitudes, and practices of influenza and pneumococcal vaccines among agricultural workers: results of an Italian a cross-sectional study

BACKGROUND

Working age is increasing across Europe. Seasonal influenza (SID) and pneumococcal disease (PND) immunization programmes might be successfully implemented at the workplace. We conducted a cross-sectional survey among to assess SID and PND vaccine status, as well as knowledge, attitudes and practices (KAP) in a representative sample of agricultural workers (AWs) aged ≥55 years in North-Eastern Italy.

METHODS

A structured questionnaire was administered in person by trained personnel. Bivariate and multivariate logistic regression analyses were carried out to identify behavioral and work-related factors associated with SID and PND vaccine uptake.

RESULTS

Among 707 participants, 238 were aged 55 years or more (33.7% of total). Of them, 39.1% had an up-to-date immunization status towards influenza, and 17.6% towards pneumococcus. Factors associated with inadequate immunization were doubts about influenza vaccine safety (40.0%) and the confidence in natural immunity towards pneumococcus (30.8%). Attitude towards vaccinations was somehow favorable in 44.5% of participants for SID, and 37.8% for PND. Overall, 37.4% and 21.8% workers were aware of national recommendations on SID and PND immunization, respectively. This factor was characterized as a significant predictor for SID vaccination (multivariated Odds Ratio, OR 32.688 95%CI 12.015-88.930), as well as the perception of SID as a severe disease (OR 7.539 95%CI 3.312-17.164), and the perceived value of preventing new infections (OR 3.215 95%CI 1.205-8.578). A somehow favorable attitude towards vaccinations was the main predictor (OR 39.214 95%CI 10.179-151.1) for PND vaccination.

CONCLUSIONS

Our study indicates that older workers lack appropriate knowledge of national recommendations and correct risk perception of SID and PND infections, but also vaccines' side effects. As the latter has been recognized as predictive factor for SID vaccination, our results stress the importance for tailored informative interventions in the workplaces aimed to increase risk perception and vaccine acceptance. (www.actabiomedica.it).

Factors and considerations for establishing and improving seasonal influenza vaccination of health workers: Report from a WHO meeting, January 16-17, Berlin, Germany

Health workers represent an important target group for seasonal influenza vaccination because of their increased risk of infection as well as the risk of transmitting infection to vulnerable patients in the health care setting. Moreover, seasonal vaccination of health workers contributes to pandemic preparedness. However, many countries, especially in Africa and Asia, do not have policies for health worker influenza vaccination. In countries where such policies exist, vaccination coverage is often low. The World Health Organization (WHO) is developing a manual to guide the introduction of seasonal influenza vaccination of health workers. An Independent External Advisory Group (IEAG) that is advising WHO on the content of the manual met to discuss issues that are relevant and often unique to health worker vaccination. This meeting report summarizes the main issues that were discussed and the outcomes of the discussion. The issues include policy considerations, including the evidence in support of health worker vaccination; categorization and prioritization of health workers; the choice of vaccination strategy; its integration into broader health worker vaccination and occupational health policies; planning and management of vaccination, particularly the approaches for communication and demand generation; and the challenges with monitoring and evaluation of health worker vaccination, especially in low and middle-income countries.

Study of Healthcare Personnel with Influenza and other Respiratory Viruses in Israel (SHIRI): study protocol

Background

The Study of Healthcare Personnel with Influenza and other Respiratory Viruses in Israel (SHIRI) prospectively follows a cohort of healthcare personnel (HCP) in two hospitals in Israel. SHIRI will describe the frequency of influenza virus infections among HCP, identify predictors of vaccine acceptance, examine how repeated influenza vaccination may modify immunogenicity, and evaluate influenza vaccine effectiveness in preventing influenza illness and missed work.

Methods

Cohort enrollment began in October, 2016; a second year of the study and a second wave of cohort enrollment began in June 2017. The study will run for at least 3 years and will follow approximately 2000 HCP (who are both employees and members of Clalit Health Services [CHS]) with routine direct patient contact. Eligible HCP are recruited using a stratified sampling strategy. After informed consent, participants complete a brief enrollment survey with questions about occupational responsibilities and knowledge, attitudes, and practices about influenza vaccines. Blood samples are collected at enrollment and at the end of influenza season; HCP who choose to be vaccinated contribute additional blood one month after vaccination. During the influenza season, participants receive twice-weekly short message service (SMS) messages asking them if they have acute respiratory illness or febrile illness (ARFI) symptoms. Ill participants receive follow-up SMS messages to confirm illness symptoms and duration and are asked to self-collect a nasal swab. Information on socio-economic characteristics, current and past medical conditions, medical care utilization and vaccination history is extracted from the CHS database. Information about missed work due to illness is obtained by self-report and from employee records. Respiratory specimens from self-collected nasal swabs are tested for influenza A and B viruses, respiratory syncytial virus, human metapneumovirus, and coronaviruses using validated multiplex quantitative real-time reverse transcription polymerase chain reaction assays. The hemagglutination inhibition assay will be used to detect the presence of neutralizing influenza antibodies in serum.

Discussion

SHIRI will expand our knowledge of the burden of respiratory viral infections among HCP and the effectiveness of current and repeated annual influenza vaccination in preventing influenza illness, medical utilization, and missed workdays among HCP who are in direct contact with patients.

Trial registration

NCT03331991. Registered on November 6, 2017.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-3444-7) contains supplementary material, which is available to authorized users.

The potential economic value of influenza vaccination for healthcare workers in The Netherlands

Background

Despite the clinical evidence, influenza vaccination coverage of healthcare workers remains low. To assess the health economic value of implementing an influenza immunization program among healthcare workers (HCW) in University Medical Centers (UMCs) in the Netherlands, a cost‐benefit model was developed using a societal perspective.

Methods/Patients

The model was based on a trial performed among all UMCs in the Netherlands that included both hospital staff and patients admitted to the pediatrics and internal medicine departments. The model structure and parameters estimates were based on the trial and complemented with literature research, and the impact of uncertainty explored with sensitivity analyses.

Results

In a base‐case scenario without vaccine coverage, influenza‐related annual costs were estimated at € 410 815 for an average UMC with 8000 HCWs and an average occupancy during the influenza period of 6000 hospitalized patients. Of these costs, 82% attributed to the HCWs and 18% were patient‐related. With a vaccination coverage of 15.47%, the societal program’s savings were € 2861 which corresponds to a saving of € 270.53 per extended hospitalization. Univariate sensitivity analyses show that the results are most sensitive to changes in the model parameters vaccine effectiveness in reducing influenza‐like illness (ILI) and the vaccination‐related costs.

Conclusion

In addition to the decreased burden of patient morbidity among hospitalized patients, the effects of the hospital immunization program slightly outweigh the economic investments. These outcomes may support healthcare policymakers’ recommendations about the influenza vaccination program for healthcare workers.

Influenza vaccination in healthcare workers: A comprehensive critical appraisal of the literature

Influenza imposes a significant burden worldwide from the healthcare and socio-economic standpoints. This is also due to suboptimal vaccination coverage among the target population, even though immunization is recommended since many years and still remains the fundamental tool for its prevention. Healthcare workers (HCWs) are at increased risk of exposure to respiratory pathogens compared with the general population, including flu, with potential threat for their health and for patients' safety. Nevertheless, despite recommendation for immunization of this work-category in most of Western Countries, inadequate flu vaccine uptake is reported during the last decade in the European area. According to recent systematic reviews on this topic, the main determinants of vaccine acceptance among HCWs have been largely investigated and include desire for self-protection and to protect family rather than absolute disease risk or desire to protect patients, among the main drivers. On the other hand, concerns regarding safety of the vaccines resulted in decreased vaccine uptake. Moreover, influenza vaccine hesitancy among HCWs was also associated with several issues such as low risk perception, denial of the social benefit of influenza vaccination, low social pressure, lack of perceived behavioral control, negative attitude toward vaccines, not having been previously vaccinated against influenza, not having previously had influenza, lack of adequate influenza-specific knowledge, lack of access to vaccination facilities, and socio-demographic variables. The topic of influenza vaccination among HCWs is challenging, full of ethical issues. Systematic reviews of randomized controlled trials (RCTs) investigating the effectiveness of interventions for improving vaccine uptake among HCWs found that combined strategies were more effective than isolate approaches. Mandatory policies are currently under debate in several countries. High quality studies would help policy-makers and stake-holders to shape evidence-based initiatives and programs to improve the control of influenza.

Medical students' attitude toward influenza vaccination: Results of a survey in the University of Bari (Italy)

Influenza vaccination is strongly recommended for Italian healthcare professionals, but vaccine coverage is low. Since 2012, vaccination is also offered to medical students as part of the National Immunization Plan; however, few Medical Schools has implemented the plan so far. To study determinants of vaccination compliance, we conducted a survey among medical students at the University of Bari, where influenza vaccination has been actively offered since 2013. Information was obtained by means of an online anonymous questionnaire administered in April 2014. We enrolled 669 students, 383 (57%) vaccinated; 54% were female and the average age was 23.9 ± 4.9 y. Determinants of getting vaccinated were analyzed in a multivariate logistic model. Receiving invitation from the University (aOR = 3.8; 95%CI = 1.2-12.3; p = 0.026), the opinion that vaccine is safe (aOR = 2.8; 95%CI = 1.5-5.0; p = 0.001) and useful (aOR = 3.4; 95%CI = 1.7-6.7; p<0.0001), a specific training about influenza vaccination during the course (aOR = 1.5; 95%CI = 1.1-2.1; p = 0.043), and considering himself as at a major risk of influenza complication (aOR = 1.8; 95% CI = 1.1-2.9; p = 0.001) were significantly associated with vaccine acceptance. Active invitation and training are confirmed as key actions (as in children vaccination strategies) and, according to our results, they could be routinely used to promote vaccination in hard-to-reach groups such as healthcare workers.

Influenza vaccination in older people with diabetes and their household contacts

BACKGROUND

People with diabetes are at a higher risk of influenza infections and severe complications. The vaccination of close contacts could offer indirect protection to people with diabetes; this is known as "herd immunity." The aim of this study is to investigate the vaccination rates of people with diabetes and their household contacts in Hong Kong.

RESEARCH DESIGN AND METHODS

Face-to-face interviews with 158 patients diagnosed with Type 2 diabetes and aged ⩾65years were conducted in clinics. Telephone interviews were then conducted with 281 adult household contacts.

RESULTS

Seasonal influenza vaccination rates were 54.5% and 27.4%, in people with diabetes and their contacts, respectively. The vaccination status of patients was not significantly associated with the vaccination of their household contacts (p=0.073). Among household contacts, children or the elderly, the partners or couples of patients, and those with more hours of daily contact, or with chronic conditions, were associated with higher vaccination rates. However, only age remained significant after adjusting for confounding factors in logistic regression models.

CONCLUSIONS

The low vaccination rates of people with diabetes and their close contacts highlight the need to promote vaccination in susceptible populations and to educate the public about herd immunity.

Influenza vaccination prevalence and demographic factors of patients and GPs in primary care in Austria and Croatia: a cross-sectional comparative study in the framework of the APRES project

BACKGROUND

The aim of this study was to compare influenza vaccination coverage rates in Austria and Croatia, countries with missing data in the Eurosurveillance and European Centre for Disease Prevention and Control reports. In addition, we assessed demographic factors of GPs and patients and calculated associations regarding vaccination rates.

METHODS

This cross-sectional study was conducted within the context of thethe appropriateness of prescribing antibiotics in primary health care in Europe with respect to antibiotic resistance (APRES) project. Between November 2010 and July 2011, 40 GP practices attempted to recruit 200 patients to complete questionnaires about their influenza vaccination status and demographics. Statistical analyses included subgroup analyses and logistic regression models.

RESULTS

Data from 7269 patient questionnaires could be analyzed (3309 Austria and 3960 Croatia). The vaccination coverage rates were low (2009/2010: A 18.2 vs. C 20.9%, P < 0.001; 2010/2011: A 13.7 vs. C 18.6%; P < 0.001). The rates were found to be highest in persons aged 65 years and older (2009/2010: A 35.1 vs. C 49.5%, P < 0.001; 2010/2011: A 31.1 vs. C 45.7%, P < 0.001) and lowest in children (2009/2010: A 8.5 vs. C 2.0%, P < 0.001; 2010/2011: A 4.3 vs. C 1.6%, P = 0.002). Besides, demographics in the adjusted regression model for Austria being vaccinated was associated with consulting a female GP (OR, 4.20; P < 0.001) and in Croatia with five or more GP consultations per year (OR, 4.41; P < 0.001).

CONCLUSION

The vaccination coverage rates for Austria and Croatia were low, with the highest rates found in persons aged 65 years and older, showing that public coverage of the vaccination costs might increase vaccination rates. However, other factors seem to be relevant, including the engagement of GPs.

Beliefs and Opinions of Health Care Workers and Students Regarding Influenza and Influenza Vaccination in Tuscany, Central Italy

Immunization of health care workers (HCWs) against influenza has been associated with improvements in patient safety. The aim of this study is to assess the beliefs, attitudes, and knowledge of HCWs and health profession students regarding influenza. An anonymous questionnaire was distributed to HCWs in three local Florentine healthcare units, at Careggi University Teaching Hospital, and to students in health profession degree programs. A total of 2576 questionnaires were fully completed. A total of 12.3% of subjects responded that they were "always vaccinated" in all three of the seasonal vaccination campaigns studied (2007-2008 to 2009-2010), 13.1% had been vaccinated once or twice, and 74.6% had not received vaccinations. Although the enrolled subjects tended to respond that they were "never vaccinated," they considered influenza to be a serious illness and believed that the influenza vaccine is effective. The subjects who refused vaccination more frequently believed that the vaccine could cause influenza and that it could have serious side effects. More than 60% of the "always vaccinated" group completely agreed that HCWs should be vaccinated. Self-protection and protecting family members or other people close to the respondent from being infected and representing potential sources of influenza infection can be considered motivating factors for vaccination. The results highlight the importance of improving vaccination rates among all HCWs through multi-component interventions. Knowledge of influenza should be reinforced.

Putting public health ethics into practice: a systematic framework

It is widely acknowledged that public health practice raises ethical issues that require a different approach than traditional biomedical ethics. Several frameworks for public health ethics (PHE) have been proposed; however, none of them provides a practice-oriented combination of the two necessary components: (1) a set of normative criteria based on an explicit ethical justification and (2) a structured methodological approach for applying the resulting normative criteria to concrete public health (PH) issues. Building on prior work in the field and integrating valuable elements of other approaches to PHE, we present a systematic ethical framework that shall guide professionals in planning, conducting, and evaluating PH interventions. Based on a coherentist model of ethical justification, the proposed framework contains (1) an explicit normative foundation with five substantive criteria and seven procedural conditions to guarantee a fair decision process, and (2) a six-step methodological approach for applying the criteria and conditions to the practice of PH and health policy. The framework explicitly ties together ethical analysis and empirical evidence, thus striving for evidence-based PHE. It can provide normative guidance to those who analyze the ethical implications of PH practice including academic ethicists, health policy makers, health technology assessment bodies, and PH professionals. It will enable those who implement a PH intervention and those affected by it (i.e., the target population) to critically assess whether and how the required ethical considerations have been taken into account. Thereby, the framework can contribute to assuring the quality of ethical analysis in PH. Whether the presented framework will be able to achieve its goals has to be determined by evaluating its practical application.

A systematic review of mandatory influenza vaccination in healthcare personnel

CONTEXT

Influenza is a major cause of patient morbidity. Mandatory influenza vaccination of healthcare personnel (HCP) is increasingly common yet has uncertain clinical impact. This study systematically examines published evidence of the benefits and harm of influenza vaccine mandates.

EVIDENCE ACQUISITION

MEDLINE, Embase, the Cochrane Library, Cumulative Index to Nursing and Allied Health Literature, Science Citation Index Expanded, and Conference Proceedings Citations Index were searched and analyzed in 2013. Studies must have assessed the effect of a requirement of influenza vaccination among HCP for continued employment or clinical practice. Studies were not limited by comparison group, outcome, language, or study design. Two reviewers independently abstracted data and assessed bias risk.

EVIDENCE SYNTHESIS

Twelve observational studies were included in the study from 778 citations. Following implementation of a vaccine mandate, vaccination rates increased in all eight studies reporting this outcome, exceeding 94%. Three studies documented increased vaccination rates in hospitals with mandates compared to those without (p<0.001 for all comparisons). Two single-institution studies reported limited, inconclusive results on absenteeism among HCP. No studies reported on clinical outcomes among patients. Medical and religious exemptions and terminations or voluntary resignations were rare.

CONCLUSIONS

Evidence from observational studies suggests that a vaccine mandate increases vaccination rates, but evidence on clinical outcomes is lacking. Although challenging, large healthcare employers planning to implement a mandate should develop a strategy to evaluate HCP and patient outcomes. Further studies documenting the impact of HCP influenza vaccination on clinical outcomes would inform decisions on the use of mandatory vaccine policies in HCP.

Vaccination coverage for seasonal influenza among residents and health care workers in Norwegian nursing homes during the 2012/13 season, a cross-sectional study

Background

WHO has set a goal of 75% vaccination coverage (VC) for seasonal influenza for residents and also recommends immunization for all healthcare workers (HCWs) in nursing homes (NHs). We conducted a cross-sectional study to estimate the VC for seasonal influenza vaccination in Norwegian NHs in 2012/2013 since the VC in NHs and HCWs is unknown.

Methods

We gathered information from NHs concerning VC for residents and HCWs, and vaccination costs for HCWs, using a web-based questionnaire. We calculated VC among NH residents by dividing the number of residents vaccinated by the total number of residents for each NH. VC among HCWs was similarly calculated by dividing the number of HCWs vaccinated by the total number of HCWs for each NH. The association between VC and possible demographic variables were explored.

Results

Of 910 NHs, 354 (38.9%) responded. Median VC per NH was 71.7% (range 0-100) among residents and 0% (range 0-100) among HCWs, with 214 (60%) NHs reporting that none of their HCWs was vaccinated. Median VC for HCWs in NHs with an annual vaccination campaign was 0% (range 0-53), compared to when they did not have an annual vaccination campaign 0% (range 0-12); the distributions in the two groups differed significantly (Mann–Whitney U, P = 0.006 two tailed).

Conclusion

Median influenza VC in Norwegian NHs was marginally lower than recommended among residents and exceptionally low among HCWs. The VC in HCWs was significantly higher when NHs had an annual vaccination campaign. We recommend that NHs implement measures to increase VC among residents and HCWs, including vaccination campaigns and studies to identify potential barriers to vaccination.

Methodological quality of systematic reviews on influenza vaccination

BACKGROUND

There is a growing body of evidence on the risks and benefits of influenza vaccination in various target groups. Systematic reviews are of particular importance for policy decisions. However, their methodological quality can vary considerably.

OBJECTIVES

To investigate the methodological quality of systematic reviews on influenza vaccination (efficacy, effectiveness, safety) and to identify influencing factors.

METHODS

A systematic literature search on systematic reviews on influenza vaccination was performed, using MEDLINE, EMBASE and three additional databases (1990-2013). Review characteristics were extracted and the methodological quality of the reviews was evaluated using the assessment of multiple systematic reviews (AMSTAR) tool. U-test, Kruskal-Wallis test, chi-square test, and multivariable linear regression analysis were used to assess the influence of review characteristics on AMSTAR-score.

RESULTS

Fourty-six systematic reviews fulfilled the inclusion criteria. Average methodological quality was high (median AMSTAR-score: 8), but variability was large (AMSTAR range: 0-11). Quality did not differ significantly according to vaccination target group. Cochrane reviews had higher methodological quality than non-Cochrane reviews (p=0.001). Detailed analysis showed that this was due to better study selection and data extraction, inclusion of unpublished studies, and better reporting of study characteristics (all p<0.05). In the adjusted analysis, no other factor, including industry sponsorship or journal impact factor had an influence on AMSTAR score.

CONCLUSIONS

Systematic reviews on influenza vaccination showed large differences regarding their methodological quality. Reviews conducted by the Cochrane collaboration were of higher quality than others. When using systematic reviews to guide the development of vaccination recommendations, the methodological quality of a review in addition to its content should be considered.

Diagnosis of influenza: only a problem of coding?

OBJECTIVE

To evaluate the characteristics of hospital discharge diagnoses of influenza measured by using specific International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9 CM) codes.

SUBJECTS AND METHODS

The study was conducted for the 3 years 2007, 2008 and 2011. The database included (1) administrative and clinical data on Sicilian patients admitted to acute care hospitals and (2) data from the influenza virological surveillance of 10 European countries (FluNet database). All Sicilian patients diagnosed with at least 1 ICD-9 CM code for influenza (487.0, 487.1 and 487.9) were considered influenza cases.

RESULTS

Overall, 2,880 patients with an ICD-9 CM code attributable to influenza were hospitalized in Sicily: 2,119 (73.6%) were admitted from November to April, whereas 761 (26.4%) were admitted from May to October. In the 3 years studied, the analyzed European influenza surveillance systems recorded a peak of laboratory-confirmed influenza activity from November to April with 36,753 (99.7%) influenza cases, whereas only 124 cases (0.3%) were observed from May to October.

CONCLUSIONS

In Sicily, more than one quarter of all hospital admissions with an ICD-9 CM code for influenza were observed in the months with a negligible circulation of influenza viruses. Our findings show that several hospital discharge records included ICD-9 CM codes for influenza with low levels of sensitivity, specificity and/or appropriateness for clinical information and support the need for improving medical education on the epidemiology and hospital management of influenza cases.

Effect of influenza vaccination of healthcare personnel on morbidity and mortality among patients: systematic review and grading of evidence

BACKGROUND

Influenza vaccination of healthcare personnel (HCP) is recommended in >40 countries. However, there is controversy surrounding the evidence that HCP vaccination reduces morbidity and mortality among patients. Key factors for developing evidence-based recommendations include quality of evidence, balance of benefits and harms, and values and preferences.

METHODS

We conducted a systematic review of randomized trials, cohort studies, and case-control studies published through June 2012 to evaluate the effect of HCP influenza vaccination on mortality, hospitalization, and influenza cases in patients of healthcare facilities. We pooled trial results using meta-analysis and assessed evidence quality using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

RESULTS

We identified 4 cluster randomized trials and 4 observational studies conducted in long-term care or hospital settings. Pooled risk ratios across trials for all-cause mortality and influenza-like illness were 0.71 (95% confidence interval [CI], .59-.85) and 0.58 (95% CI, .46-.73), respectively; pooled estimates for all-cause hospitalization and laboratory-confirmed influenza were not statistically significant. The cohort and case-control studies indicated significant protective associations for influenza-like illness and laboratory-confirmed influenza. No studies reported harms to patients. Using GRADE, the quality of the evidence for the effect of HCP vaccination on mortality and influenza cases in patients was moderate and low, respectively. The evidence quality for the effect of HCP vaccination on patient hospitalization was low. The overall evidence quality was moderate.

CONCLUSIONS

The quality of evidence is higher for mortality than for other outcomes. HCP influenza vaccination can enhance patient safety.

Evaluating a standardized measure of healthcare personnel influenza vaccination

BACKGROUND

Methods of measuring influenza vaccination of healthcare personnel (HCP) vary substantially, as do the groups of HCP that are included in any given set of measurements. Thus, comparison of vaccination rates across healthcare facilities is difficult.

PURPOSE

The goal of the study was to determine the feasibility of implementing a standardized measure for reporting HCP influenza vaccination data in various types of healthcare facilities.

METHODS

A total of 318 facilities recruited in four U.S. jurisdictions agreed to participate in the evaluation, including hospitals, long-term care facilities, dialysis clinics, ambulatory surgery centers, and physician practices. HCP in participating facilities were categorized as employees, credentialed non-employees, or other non-employees using standard definitions. Data were gathered using cross-sectional web-based surveys completed at three intervals between October 2010 and May 2011; data were analyzed in February 2012.

RESULTS

234 facilities (74%) completed all three surveys. Most facilities could report on-site employee vaccination; almost one third could not provide complete data on HCP vaccinated outside the facility, contraindications, or declinations, primarily due to missing non-employee data. Inability to determine vaccination status of credentialed and other non-employees was cited as a major barrier to measure implementation by 24% and 27% of respondents, respectively.

CONCLUSIONS

Using the measure to report employee vaccination status was feasible for most facilities; tracking non-employee HCP was more challenging. Based on evaluation findings, the measure was revised to limit the types of non-employees included. Although the revised measure is less comprehensive, it is more likely to produce valid vaccination coverage estimates. Use of this standardized measure can inform quality improvement efforts and facilitate comparison of HCP influenza vaccination among facilities.

Predictive factors associated with the acceptance of pandemic and seasonal influenza vaccination in health care workers and students in Tuscany, Central Italy

Assessing the beliefs and attitudes of Health Care Workers (HCW) to influenza and influenza vaccination can be useful in overcoming low compliance rates. The purpose of our study is to evaluate the opinion of HCW and students regarding influenza, influenza vaccine and the factors associated with vaccination compliance. A survey was conducted between October 2010 and April 2011 in the Florence metropolitan area. A questionnaire was administered to HCW in three local healthcare units and at Careggi University Teaching Hospital. Students matriculating in health degree programs at Florence University were also surveyed.

The coverage with vaccination against seasonal and pandemic influenza is generally low, and it is lower in students than in HCW (12.5% vs 15% for the seasonal vaccination, 8.5% vs 18% for the pandemic vaccination). Individuals comply with vaccination offer mainly to protect themselves and their contacts. Individuals not receiving vaccination did not consider themselves at risk, had never been vaccinated before or believed that pandemic influenza was not a public health concern. Physicians had the highest compliance to vaccination and women were less frequently vaccinated than men. HCW do not appear to perceive their possible influenza infections as a risk for patients: HCW receive vaccination mainly as a form of personal protection.

Low compliance to vaccination is determined by various factors and therefore requires a multi-faceted strategy of response. This should include short-term actions to overcome organizational barriers, in addition to long-term interventions to raise HCW’s level of knowledge about influenza and influenza vaccination.

Planning and process evaluation of a multi-faceted influenza vaccination implementation strategy for health care workers in acute health care settings

BACKGROUND

Influenza transmitted by health care workers (HCWs) is a potential threat to frail patients in acute health care settings. Therefore, immunizing HCWs against influenza should receive high priority. Despite recommendations of the World Health Organization, vaccine coverage of HCWs remains low in all European countries. This study explores the use of intervention strategies and methods to improve influenza vaccination rates among HCWs in an acute care setting.

METHODS

The Intervention Mapping (IM) method was used to systematically develop and implement an intervention strategy aimed at changing influenza vaccination behaviour among HCWs in Dutch University Medical Centres (UMCs). Carried out during the influenza seasons 2009/2010 and 2010/2011, the interventions were then qualitatively and quantitatively evaluated by way of feedback from participating UMCs and the completion of a web-based staff questionnaire in the following spring of each season.

RESULTS

The IM method resulted in the development of a transparent influenza vaccination intervention implementation strategy. The intervention strategy was offered to six Dutch UMCs in a randomized in a clustered Randomized Controlled Trial (RCT), where three UMCs were chosen for intervention, and three UMCs acted as controls. A further two UMCs elected to have the intervention. The qualitative process evaluation showed that HCWs at four of the five intervention UMCs were responsive to the majority of the 11 relevant behavioural determinants resulting from the needs assessment in their intervention strategy compared with only one of three control UMCs. The quantitative evaluation among a sample of HCWs revealed that of all the developed communication materials, HCWs reported the posters as the most noticeable.

CONCLUSIONS

Our study demonstrates that it is possible to develop a structured implementation strategy for increasing the rate of influenza vaccination by HCWs in acute health care settings. The evaluation also showed that it is impossible to expose all HCWs to all intervention methods (which would have been the best case scenario). Further study is needed to (1) improve HCW exposure to intervention methods; (2) determine the effect of such interventions on vaccine uptake among HCWs; and (3) assess the impact on clinical outcomes among patients when such interventions are enacted.

Knowledge, attitudes and beliefs of health care workers towards influenza vaccination

BACKGROUND

Influenza vaccination is routinely offered to health care workers in the U.K. to prevent nosocomial spread to patients and illness among health care workers. Despite its importance uptake has been low in the U.K.

AIMS

To describe the knowledge, attitudes and behaviour of health care workers towards influenza vaccination offered as part of occupational health and to understand their relative importance in promoting uptake of influenza vaccine. We also sought to make comparisons with other vaccines more readily accepted as part of occupational health.

METHODS

An online survey was distributed by e-mail to health care workers in the South Central Strategic Health Authority. The questionnaire included the following: demographic characteristics; vaccination status; and knowledge, attitudes and behaviour towards influenza, MMR and hepatitis B vaccination. We used logistic regression to identify the independent predictors of receipt of influenza vaccine.

RESULTS

The survey was completed by 998 health care workers representing just over 1% of health care workers in the region. Of those, 69% thought that overall benefits of influenza vaccination were greater than the risks and inconvenience (versus 92% for hepatitis B and 86% for MMR). The following predicted receipt of influenza vaccine: belief that influenza poses a risk to one's own health (OR 3.74; 95% CI 2.45-5.71); belief that influenza vaccine is harmful (OR 0.25; 95% CI 0.16-0.37); and belief that influenza vaccine will protect patients (OR 2.96; 95% CI 1.89-4.62).

CONCLUSIONS

Staff knowledge, attitudes and beliefs concerning influenza and its vaccine are an important predictor of uptake and should be a target for campaigns to promote uptake.

[Influenza vaccination rates in Hessian hospitals]

Influenza infections have been shown to spread in hospitals rapidly; nosocomial transmissions occur frequently. Influenza vaccination of health care personnel (HCP) is an effective strategy for preventing influenza infections among personnel and patients. In summer 2011 we conducted an anonymous questionnaire among Hessian hospitals assessing influenza vaccination rates, kind and concept of vaccination programmes. Overall, 95.8% (68/71) of hospitals surveyed offered influenza vaccinations for HCP free of charge. Influenza vaccination rates have been recorded only by 70.4% (50/71). Over 80% (season 2009/2010: 41/50- season 2010/2011: 44/50) of hospitals questioned, mentioned influenza vaccination rates under 20%. Our findings confirm that the influenza vaccination rates might be less than the generally assumed and communicated influenza vaccination rates of 20-25%. Thirty years since the German Standing Committee on Vaccination (STIKO) recommended that all HCP get vaccinated against influenza, vaccination rates still remain below 30%. Measures to improve influenza vaccination rates among HCP are required. Monitoring of vaccination rates is a precondition to assess the acceptance of a vaccination programme.

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.

Effectiveness of influenza vaccine in aging and older adults: comprehensive analysis of the evidence

Foremost amongst the diseases preventable by vaccination is influenza. Worldwide, influenza virus infection is associated with serious adverse events leading to hospitalization, debilitating complications, and death in elderly individuals. Immunization is considered to be the cornerstone for preventing these adverse health outcomes, and vaccination programs are timed to optimize protection during the annual influenza season. Trivalent inactivated influenza virus vaccines are believed to be both effective and cost-saving; however, in spite of widespread influenza vaccination programs, rates of hospitalization for acute respiratory illness and cardiovascular diseases have been increasing in this population during recent annual influenza seasons. From meta-analyses summarizing estimates of influenza vaccine effectiveness from available observational clinical studies, this review aims to examine how effective current influenza vaccine strategies are in the aging and older adult population and to analyze which are the most important biases that interfere with measurements of influenza vaccine effectiveness. Furthermore, consideration is given to strategies that should be adopted in order to optimize influenza vaccine effectiveness in the face of immune exhaustion.

Influenza vaccination in the face of immune exhaustion: is herd immunity effective for protecting the elderly?

At the start of the 21st century, seasonal influenza virus infection is still a major public health concern across the world. The recent body of evidence confirms that trivalent inactivated influenza vaccines (TIVs) are not optimal within the population who account for approximately 90% of all influenza-related death: elderly and chronically ill individuals regardless of age. With the ever increasing aging of the world population and the recent fears of any pandemic influenza rife, great efforts and resources have been dedicated to developing more immunogenic vaccines and strategies for enhancing protection in these higher-risk groups. This paper describes the mechanisms that shape immune response at the extreme ages of life and how they have been taken into account to design more effective immunization strategies for these vulnerable populations. Furthermore, consideration will be given to how herd immunity may provide an effective strategy in preventing the burden of seasonal influenza infection within the aged population.