Influenza vaccination in Austria from 1982 to 2011: A country resistant to influenza prevention and control

Factors driving choices between types and brands of influenza vaccines in general practice in Austria, Italy, Spain and the UK

Influenza vaccine effectiveness (IVE) assessment is increasingly stratified by vaccine type or brand, such as done by the European network of DRIVE. In 2019/2020, eleven influenza vaccines were licensed in Europe. If more than one vaccine type is recommended or if more than one vaccine brand is available for a specific risk group, it is not clear which factors affect the choice of a specific vaccine (type or brand) by a health practitioner for individual patients. This is important for IVE assessment. A survey tailored to the 2019/20 local vaccine recommendations was conducted among GPs in four European countries (Austria, Italy, Spain, UK) to understand how influenza vaccine is offered to recommended risk groups and, if GPs have a choice between 2 or more vaccines, what factors influence their vaccine choice for patients. Overall, 360 GPs participated. In Austria, Italy and Spain GPs indicated that influenza vaccines are commonly offered when patients present for consultation, whereas in the UK all GPs indicated that all relevant patients are contacted by letter. In Austria and Italy, roughly 80% of GPs had only one vaccine type available for patients <65y. The use of any specific vaccine type in this age group is mostly determined by the availability of specific vaccine type(s) at the clinic. GPs frequently reported availability of more than one vaccine type for patients ≥65y in Austria (45%), Italy (70%) and Spain (79%). In this group, patient characteristics played a role in choice of vaccine, notably older age and presence of (multiple) comorbidities. Knowing that a non-patient related factor usually determines the vaccine type a patient receives in settings where more than one vaccine type is recommended for risk groups <65y, simplifies IVE assessment in this age group. However, patient characteristics need careful consideration when assessing IVE in those ≥65y.

Influenza vaccination uptake and factors influencing vaccination decision among patients with chronic kidney or liver disease

Introduction

Seasonal influenza is a major global health problem causing substantial morbidity and health care costs. Yet, in many countries, the rates of influenza vaccination remain low. Chronic kidney or liver diseases (CKLD) predispose patients to severe influenza infections, but data on vaccination acceptance and status is limited in this risk population. We investigated the influenza vaccination awareness considering sociodemographic factors in CKLD patients.

Patients and methods

This cross-sectional, questionnaire-based study recruited CKLD patients managed at three Viennese tertiary care centers between July and October 2020. CKLD was defined as chronic kidney- (all stages) or compensated/decompensated liver disease, including kidney/liver transplant recipients. Questionnaires assessed sociodemographic and transplant- associated parameters, patients vaccination status and the individuals self-perceived risks of infection and associated complications.

Results

In total 516 patients (38.1% female, mean age 56.4 years) were included. 43.9% of patients declared their willingness to be vaccinated in the winter season 2020/2021, compared to 25.4% in 2019/2020 and 27.3% in 2016–2018. Vaccination uptake was associated with the self-perceived risks of infection (OR: 2.8 (95%CI: 1.8–4.5), p<0.001) and associated complications (OR: 3.8 (95%CI: 2.3–6.3), p<0.001) as well as with previously received influenza vaccination (2019/2020: OR 17.1 (95%CI: 9.5–30.7), p<0.001; season 2016–2018: OR 8.9 (95%CI: 5.5–14.5), p<0.001). Most frequent reasons for not planning vaccination were fear of a) graft injury (33.3%), b) complications after vaccination (32.4%) and c) vaccine inefficiency (15.0%).

Conclusion

While influenza vaccination willingness in patients with CKLD is increasing in the 2020/2021 season, vaccination rates may still remain <50%. Novel co-operations with primary health care, active vaccination surveillance and financial reimbursement may substantially improve vaccination rates in high-risk CKLD patients.

Predictors for influenza vaccine acceptance among patients with inflammatory rheumatic diseases

BACKGROUND

Patients with inflammatory rheumatic diseases are at higher risk for influenza and current guidelines recommend vaccination for this group of patients. The aim of this study was to evaluate the vaccination coverage and predictors for influenza vaccination among patients with inflammatory rheumatic diseases.

METHODS

This survey was conducted at the outpatient rheumatology clinic at the Medical University of Vienna between July and October 2017. All patients diagnosed with an inflammatory rheumatic disease and receiving immunosuppressive therapy were asked to complete a questionnaire about their influenza vaccination status for 2016/17.

RESULTS

490 patients with rheumatic diseases completed a questionnaire (33% male, mean age 55.3 years). The influenza vaccination rate for the previous season was 25.3% (n = 124/490). Predictors for a positive influenza vaccination status were higher age (Adjusted Odds Ratio 5.0, 95% Confidence Interval 2.4-10.4) and treatment with biological disease-modifying antirheumatic drugs (AOR 2.0, 95% CI 1.3-3.1). Patients who received a recommendation for influenza vaccination by their general practitioner were significantly more likely to be vaccinated than those who did not (57% vs. 15%, AOR 6.6, 95% CI 4.1-10.8); even more so if they received a recommendation by their rheumatologist (62% vs. 19%, AOR 9.0, 95% CI 4.9-16.5). The main reasons for patients to decline influenza vaccination were fear of side effects (36%), concerns that vaccination might not be effective due to their immunosuppressed condition (38%) or that it might worsen the rheumatic disease (20%).

CONCLUSIONS

A moderate influenza vaccination rate of 25.3% was detected among patients with inflammatory rheumatic diseases. Recommendation of the influenza vaccine by a physician exerts the most effective impact on a positive vaccination status.

[Immunizing is not only a children's matter! : Why vaccinations are also important for adults]

Vaccinations belong to the ten most effective public health achievements worldwide. While immunization programms for children are installed in Europe, vaccinations for adults are not established. However, adult vaccination is extremely meaningful: increasing age means a higher susceptibility to infectious diseases, health problems and multimorbidity will increase. The burden of vaccine-preventable diseases is still high in Europe. Due to immunosenescence (older) adults are less protected against pathogens, antibody titers after vaccinations are lower and immunity lasts shorter. There is striking lack of data of adult vaccination rates and an international consensus regarding adult vaccination recommendations or guidelines are not available in Europe. In only six countries a comprehensive document describing recommended vaccinations for adults is available, among them Austria. The awareness of the importance of adult vaccination over the whole lifetime is not present to the necessary extent in Europe and has to be promoted.

Translation of the UK Pediatric Influenza Vaccination Programme in Primary Schools to 13 European Countries Using a Dynamic Transmission Model

Objectives: To simulate the impact of a pediatric influenza vaccination programme using quadrivalent live attenuated influenza vaccine (QLAIV) in Europe by applying coverage rates achieved in the United Kingdom during the 2014-2015 season and to compare the model outcomes to the UK results. Methods: We used a deterministic, age-structured, dynamic transmission model adapted to the demography, contact patterns and influenza incidence of 13 European countries, with a 10-year horizon. The reference strategy was the unchanged country-specific coverage rate, using quadrivalent inactivated vaccine (assumed efficacy against infection from 45% in 1-year-old children to 60% in healthy adults). In the evaluated strategy, 56.8% of 5-10-year-old children were additionally vaccinated with QLAIV (assumed efficacy 80%), as was the case in 2014-2015 in the United Kingdom's primary school pilot areas. Symptomatic influenza cases and associated medical resources (primary care consultations [PCC], hospitalization, intensive care unit [ICU] admissions) were calculated. The evaluated versus reference strategies were compared using odds ratios (ORs) for PCC in the target (aged 5-10-years) and non-target adult (aged >17 years) populations as well as number needed to vaccinate (NNV) with QLAIV to avert one PCC, hospitalization or ICU admission. Model outcomes, averaged over 10 seasons, were compared with published real-life data from the United Kingdom for the 2014-2015 season. Results: Over 13 countries and 10 years, the evaluated strategy prevented 32.8 million of symptomatic influenza cases (172.3 vs 205.2 million). The resulting range of ORs for PCC was 0.18-0.48 among children aged 5-10-years, and the published OR in the United Kingdom was 0.06 (95% confidence interval [0.01; 0.62]). In adults, the range of ORs for PCC was 0.60-0.91 (UK OR=0.41 [0.19; 0.86]). NNV ranges were 6-19 per averted PCC (UK NNV=16), 530-1524 per averted hospitalization (UK NNV=317) and 5298-15 241 per averted ICU admission (UK NNV=2205). Conclusions: Across a range of European countries, our model shows the beneficial direct and indirect impact of a paediatric vaccination programme using QLAIV in primary school-aged children, consistent with what was observed during a single season in the United Kingdom. Recommendations for the implementation of pediatric vaccination programmes are, therefore, supported in Europe.

Direct and Indirect Protection with Pediatric Quadrivalent Live-Attenuated Influenza Vaccination in Europe Estimated by a Dynamic Transmission Model

Objectives: To estimate the public health impact of annual vaccination of children with a quadrivalent live-attenuated influenza vaccine (QLAIV) across Europe. Methods: A deterministic, age-structured, dynamic model was used to simulate influenza transmission across 14 European countries, comparing current vaccination coverage using a quadrivalent inactivated vaccine (QIV) to a scenario whereby vaccination coverage was extended to 50% of 2-17 year-old children, using QLAIV. Differential equations described demographic changes, exposure to infectious individuals, recovery and immunity dynamics. For each country, the basic reproduction number (R0) was calibrated to published influenza incidence statistics. Assumed vaccine efficacy for children was 80% (QLAIV) and 59% (QIV). Symptomatic cases cumulated over 10 years were calculated per 100 000 person-years. One-way sensitivity analyses were conducted on QLAIV efficacy in 7-17 year-olds (59% instead of 80%), durations of natural (±3 years; base case: 6, 12 years for influenza A, B respectively) and QLAIV vaccine-induced immunity (100% immunity loss after 1 season; base case: 30%), and R0 (+/-10% around all-year average value). Results: Across countries, annual QLAIV vaccination additionally prevents 1366-3604 symptomatic cases per 100 000 population (average 2495 /100 000, ie, a reduction of 47.6% of the cases which occur in the reference scenario with QIV vaccination only). Among children (2-17 years), QLAIV prevents 551-1555 cases per 100 000 population (average 990 /100 000, ie, 67.2% of current cases). Among adults, QLAIV indirectly prevents 726-2047 cases per 100 000 population (average 1466 /100 000, ie, 40.0% of current cases). The most impactful drivers of total protection were duration of natural immunity against influenza A, R0 and QLAIV immunity duration and efficacy. In all evaluated scenarios, there was a large direct and even larger indirect protection compared with the reference scenario. Conclusions: The model highlights direct and indirect protection benefits when vaccinating healthy children with QLAIV in Europe, across a range of demographic structures, contact patterns and vaccination coverage rates.

Vaccine hesitancy in Austria : A cross-sectional survey

BACKGROUND

Vaccine hesitancy is an emerging phenomenon particularly in industrialized nations. It has led to repeated epidemic outbreaks of otherwise vaccine-preventable, infectious diseases. Compared to other countries very low rates of influenza and measles vaccination rates have been reported in Austria.

METHODS

We performed a single-center cross-sectional, questionnaire-based survey. A total of 350 adult patients attending our emergency room participated in this survey. We assessed knowledge and attitudes towards vaccination and the associated infectious diseases.

RESULTS

Out of 350 participants 40 (11.4 %) declared that they deliberately refused vaccinations. Most common reasons for non-vaccination were fear of adverse effects (35.9 %), doubt of effectiveness of vaccines (35.9 %) and distrust towards the pharmaceutical industry (23.1 %). Of all 350 participants only 148 (42.3 %) thought themselves to be sufficiently informed about national vaccination recommendations as stated in the Austrian National Vaccination Program (ANVP). General practitioners (GP) were the primary source of healthcare-related information for 256 (73.1 %) participants. Furthermore, GPs as well as hospital-based physicians achieved the highest level of trust in this study population.

CONCLUSIONS

The results of our study underline the necessity of comprehensive informational campaigns on the merits of vaccination. A lack of knowledge about the benefits of vaccination, uncertainty and unfounded fears seem to prevent the achievement of recommended vaccination rates. Family GPs enjoyed the highest levels of trust in our study population. We believe that additional information communicated by GPs could help boost the low vaccination rates. This study underlines the important role of primary care practitioners in informing patients about vaccines and healthcare topics.

Detailed Report on 2014/15 Influenza Virus Characteristics, and Estimates on Influenza Virus Vaccine Effectiveness from Austria's Sentinel Physician Surveillance Network

BACKGROUND

Influenza vaccine effectiveness (VE) is influenced by the antigenic similarity between vaccine- and circulating strains.

MATERIAL AND METHODS

This paper presents data obtained by the Austrian sentinel surveillance system on the evolution of influenza viruses during the season 2014/15 and its impact on influenza vaccine effectiveness in primary care in Austria as estimated by a test-negative case control design. VE estimates were performed for each influenza virus type/subtype, stratified by underlying diseases and adjusted for age, sex and calendar week of infection.

RESULTS

Detailed genetic and antigenic analyses showed that circulating A(H3N2) viruses were genetically distinct from the 2014/15 A(H3N2) vaccine component indicating a profound vaccine mismatch. The Influenza A(H1N1)pdm09 viruses were antigenically conserved and matched the respective vaccine component. Influenza B viruses were lineage-matched B/Yamagata viruses with a clade-level variation. Consistent with substantial vaccine mismatch for the A(H3N2) viruses a crude overall VE of only 47% was estimated, whereas the VE estimates for A(H1N1)pdm09 were 84% and for influenza B viruses 70%. Increased VE estimates were obtained after stratification by underlying diseases and adjustment for the covariates sex and age, whereby the adjustment for the calendar week of infection was the covariate exerting the highest influence on adjusted VE estimates.

CONCLUSION

In summary, VE data obtained in this study underscore the importance to perform VE estimates in the context of detailed characterization of the contributing viruses and also demonstrate that the calendar week of influenza virus infection is the most important confounder of VE estimates.

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.

Associations between the prevalence of influenza vaccination and patient's knowledge about antibiotics: a cross-sectional study in the framework of the APRES-project in Austria

Background

This study aimed to identify associations between GP patient’s knowledge about the spectrum of effectiveness of antibiotics and the probability of vaccination against influenza. The underlying hypothesis was that individuals with an understanding that antibiotics are ineffective against viruses, common colds, and flu were more likely to be vaccinated than persons lacking this knowledge.

Methods

This cross-sectional study was conducted within the context of the European APRES project in Austria. Between November 2010 and July 2011, patients were recruited from GP practices to complete questionnaires about their knowledge about antibiotics and their influenza vaccination status. Statistical analyses included subgroup analyses and logistic regression models.

Results

Data of 3224 patients was analyzed, demonstrating that patients with better knowledge concerning antibiotics had a significantly higher likelihood of being vaccinated (OR 1.35, CI 95 % 1.18–1.54). While the overall vaccination rate was low (18.6 % in 2009/2010 and 14.0 % in 2010/2011), elderly compared to younger adults (OR 0.06 CI 95 % 0.03–0.13) and healthcare workers (OR 2.24, CI 95 % 1.42–3.54) demonstrated higher likelihood of vaccination. Additionally, female GPs had significantly more vaccinated patients than male GPs (OR 2.90, CI 95 % 1.32–6.40).

Discussion

There has been little prior study on the association between a patient’s knowledge of the effectiveness spectrum of antibiotics and influenza vaccination status. Given the public health imperative to increase annual prevalence of influenza vaccination, understanding this educational gap can improve specificity in counseling as well as vaccination rates. Ultimately, we found that those with a better knowledge on about antibiotics had a significantly higher likelihood of being vaccinated.

Conclusions

The results of this study demonstrate that vaccination prevalence is associated with patient’s knowledge about antibiotics. It can be concluded that one strategy to improve the overall low vaccination rates for seasonal influenza in Austria would be, particularly for male GPs, to have a specific discussion with patients about these circumstances by focusing on younger patients. Further, public health efforts could supplement in-office strategies to improve this area of health literacy.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-015-2297-x) contains supplementary material, which is available to authorized users.

Factors associated with uptake of influenza vaccine in people aged 50 to 64 years in Hong Kong: a case-control study

Background

In Hong Kong, people aged 50–64 years were added as a recommended priority group (recommended group) for influenza vaccination by the Department of Health (DH) starting from 2011/12 onwards. The coverage rate of influenza vaccination for this age group was suboptimal at 8.5 % in 2012/13. This study investigates the factors associated with the uptake of influenza vaccination among adults in Hong Kong aged 50–64 years.

Methods

A case–control study was conducted in communities by street intercept interviews from 17 July to 15 August 2013. Cases were adults aged 50–64 years who had received the influenza vaccine in 2011/12 or 2012/13, while controls were the same as the cases, except they had not received the influenza vaccine in 2011/12 or 2012/13. Multiple logistic regression analysis was performed on the data to explore the associations between vaccination status and the variables.

Results

Six hundred and four respondents in total were interviewed and included in the analysis. There were 193 cases (vaccinated) and 411 controls (non-vaccinated), with a case-to-control ratio of 1:2.1. The following were strongly associated with vaccination compared to other factors: ‘eligible for free government vaccine’ (OR6.38, 95 % CI, 3.43-11.87, p < 0.001); ‘willing to receive flu vaccination for free’ (OR4.84, 95 % CI, 2.13-11.03, p < 0.001); ‘perceived having severe or moderate symptoms when contracting flu’ (OR2.90, 95 % CI, 1.21-6.97, p = 0.02), and ‘convenient to reach a vaccination location’ (OR2.87, 95 % CI, 1.06-7.74, p = 0.04). The majority of the cases (80.8 %) and controls (93.9 %) were not aware that they belonged to a recommended group for influenza vaccination and most (>80 %) were willing to be vaccinated if it was free.

Conclusions

Factors related to free and convenient vaccination, the perception of the severity of symptoms when contracting influenza had a comparatively strong association with influenza vaccination uptake amongst 50–64 year olds, compared to other factors.

Trends in inequalities in health, risk and preventive behaviour among the advanced-age population in Austria: 1983-2007

BACKGROUND

Although a number of previous research studies have focused on the long-term analysis of the health and health behaviour of the elderly, there is still a shortage of information in relation to the long-term trends regarding health or risk and preventive behaviour in the elderly population taking into account gender differences and differences in educational level.

METHODS

The database comprised subsamples of the Austrian Micro-Census, including individuals aged 65 years and older, for the years 1983, 1991, 1999, and subsamples of the ATHIS (Austrian Health Interview Survey) 2007. A trend analysis was conducted for four health-related variables with the year of the survey and education as predictors. The analysis was stratified by sex.

RESULTS

We found a general trend towards better self-rated health, better preventive and less risk behaviour among the elderly, while the body mass index has been increasing over the years. There are indeed gender differences regarding the trend in smoking behaviour. While the prevalence of male smoking has been steadily decreasing, female smoking prevalence has not changed. At all points in time, individuals with higher education had significantly better self-rated health than those with lower education but the association between education and preventive behaviour significantly decreased over the years.

CONCLUSION

We agree with previous research in concluding that preventive action and health promotion should aim in particular to support older women and men with lower education.

Stress, schizophrenia and bipolar disorder

The role of stress in precipitating psychotic episodes in schizophrenia and bipolar disorder has long been acknowledged. However, the neurobiological mechanism/s of this association have remained elusive. Current neurodevelopmental models of psychosis implicate early dysfunction in biological systems regulating hypothalamic-pituitary-adrenal axis and immune function, with long-term effects on the development of the brain networks responsible for higher order cognitive processes and stress reactivity in later life. There is also increasing evidence of childhood trauma in psychosis, and its impact on the development of brain systems regulating stress. These findings are emerging in the context of a new era of epigenetic methods facilitating the study of environmental effects on gene expression. The evidence is thus converging: exposure to stress at critical periods in life may be an important factor in the development of the brain dysfunction that represents psychosis vulnerability, rather than merely interacting with an independent 'biological vulnerability' to manifest in psychosis.