Dutch influenza vaccination rate drops for fifth consecutive year
Introduction
Annual vaccination can prevent influenza in the at-risk population effectively, and vaccination programs have therefore been provided in a number of countries. Influenza vaccination prevents the disease and its consequences in the most vulnerable populations such as the elderly, those with diabetes, cardiovascular or pulmonary conditions [1], [2], [3]. WHO-guidance indicates developed countries should aim to achieve 75% influenza vaccine coverage in older people, while the European Union Council (EC) advises vaccination in 75% of the at-risk population [4], [5].
In several countries monitoring programs have been established to obtain data on the reach of vaccination programs in terms of numbers needed to vaccinate and the vaccination rate of the at-risk population. Box 1 describes the Dutch influenza vaccination and monitoring program. With the results of monitoring programs, it is also possible to estimate the spending of public funds in implementing vaccination programs [6]. Influenza vaccination rates differ widely between countries, figures found in literature vary from about 40% to about 75% of the target population [1], [2], [7], [8], [9]. Uptake rates have been found to be associated with patient level issues (moreover, specific at-risk groups respond differently, and flu shot acceptance is related to multi-morbidity and older age) as well as organizational factors (like reminders or use of information pamphlets) [10], [11], [12], [13], [14], [15].
Monitoring vaccination rates is an integral part of vaccination programs. The actual numbers played an important role in the public debate [16], [17], [18], [19] that developed following the outbreak of Influenza A(H1N1)pdm09 virus (colloquially referred to as “Swine flu”) and its vaccination campaign in 2009 [20], [21]. As in other countries, in The Netherlands seasonal immunization programs were supplemented with extra vaccinations to mitigate the transmission of the A(H1N1)pdm09 virus [21], [22], [23]. Initially, the influenza A(H1N1)pdm09 virus was expected to lead to increased morbidity and mortality, but it turned out that this flu strain was mild [24]. However, public debates were seen in relation to the definition of a pandemic, the effectiveness of any vaccination program, the costs involved, and the way the pandemic was reported in the media [16], [17], [18], [19].
The aim of our study is to describe the trend in influenza vaccination rate over the years 2008 to 2013 overall and in specific target groups of patients with cardiovascular diseases, lung diseases, diabetes and the elderly. Because the number of patients at risk is also varying over the years, in this trend analyses the size of the at risk population is taken into account. This descriptive study retrospectively assesses and compares the characteristics of patients at-risk for influenza and their vaccination state in a large family practice (FP) database representative for the general adult population of The Netherlands.
Section snippets
Design and study population
In an observational longitudinal study, anonymous data from computerized medical record systems (CMRS) in family practices were used to calculate the influenza vaccination rate in the years 2008–2013 overall and for the different main at-risk groups. The family practices participated in a nationally representative network, the Netherlands Information Network of FPs (LINH) and the staff in the family practices routinely record encoded patient information of all patients, using a CMRS [11], [25],
Ethical considerations
Data collection within the LINH network was conducted in accordance with the Dutch legislation on privacy [34] and the Declaration of Helsinki [35]. Each patient record in the database is coded with an anonymous administrative number. The key to this coding number is only in the family practice. According to the Dutch Central Committee on Research Involving Human Subjects, obtaining informed consent is not obligatory for observational studies, so no medical ethical committee approval was
Results
Between 2008 and 2013 respectively 56, 72, 69, 68, 61 and 45 family practices could be included in our study, with over 175,000 listed patients per year (Table 1). The total study population (all listed patients) was representative for the Dutch population on patients’ ages and gender.
In the 2008 vaccination season, 30.5% of all patients were identified as being at risk because of having at least one of the chronic conditions or because of their age. This percentage significantly increased to
Discussion
For years, the Dutch influenza vaccination rate in the target population was relatively high compared to international figures. However, since 2008 a downward trend has been identified, resulting in a vaccination rate of 59.6% of the population at risk in 2013. The decrease was seen in all target populations, but mainly the group of the ‘healthy’ elderly. In the meantime the size of the population at risk increased slowly each year.
Despite the availability of safe and effective vaccines, and a
Conclusion
For the fifth subsequent year, there is a lowering trend of the influenza vaccination rate in the population at risk in the Netherlands. Exact causes are unknown. However, in the mass media the effectiveness of the vaccination program is discussed more and more often, and that probably affects patients and healthcare providers in reducing the uptake-rate. Moreover, it is possible that the relatively light outbreaks of seasonal influenza in the past years might have taken away the sense of
Conflict of interest/disclosure statement
The authors declare there is no conflict of interest and no financial disclosures were reported by the authors of this paper.
Acknowledgements
We would like to thank all the staff at the practices (family physicians and practice assistants) of the National Information Network of GPs (LINH) for their support. This project gave rise to an immense dataflow, so we would like to thank all the members of the LINH project team for their assistance with data collection, handling and cleaning. The study was supported financially by the National Institute for Public Health and the Environment in the Netherlands [RIVM, Centrum voor
References (43)
- et al.
Vaccination coverage rates in eleven European countries during two consecutive influenza seasons
J Infect
(2009) Seasonal influenza vaccine provision in 157 countries (2004–2009) and the potential influence of national public health policies
Vaccine
(2011)- et al.
Patient characteristics determine differences in the influenza vaccination rate more so than practice features
Prev Med
(2002) - et al.
Predictors of influenza vaccine acceptance among healthy adults
Prev Med
(1999) - et al.
Vaccination of high-risk patients against influenza: impact on primary care contact rates during epidemics: analysis of routinely collected data
Vaccine
(2004) - et al.
Pandemic influenza A(H1N1)pdm09 improves vaccination routine in subsequent years: a cohort study from 2009 to 2011
Vaccine
(2013) - et al.
Negative trends from 2008/9 to 2011/12 seasons in influenza vaccination coverages among high risk subjects and health care workers in Spain
Vaccine
(2014) - et al.
Influenza vaccination: health impact and cost effectiveness among adults aged 50 to 64 and 65 and older
Am J Prev Med
(2006) - et al.
The core of computer based patient records in family practice: episodes of care classified with ICPC
Int J Biomed Comput
(1996) - et al.
Vaccination coverage against 2009 seasonal influenza in chronically ill children and adults: analysis of population registries in primary care in Madrid (Spain)
Vaccine
(2010)
Influenza vaccination coverage – United States, 2000–2010
56th World Health Assembly. Prevention and control of influenza pandemics and annual epidemics
Council of the European Union: council recommendation of 22 December 2009 on seasonal influenza vaccination (2009/1019/EU)
Off J Eur Union
Nationaal programma grieppeventie: het succes van de griepprik
Influenza vaccination coverage among high-risk groups in 11 European countries
Eur J Public Health
Influenza vaccination in Europe: an inventory of strategies to reach target populations and optimise vaccination uptake
Eur Surveill
Improving influenza vaccination coverage among high-risk patients: a role for computer-supported prevention strategy
Fam Pract
Influenza vaccination. Are we doing better than we think?
Arch Intern Med
Social determinants of health and seasonal influenza vaccination in adults ≥65 years: a systematic review of qualitative and quantitative data
BMC Public Health
Effectiveness of a co-ordinated nation-wide programme to improve influenza immunisation rates in The Netherlands
Scand J Prim Health Care
Cited by (0)
- 1
IQ healthcare – Radboudumc, PO Box 9101/114 IQ healthcare, 6500 HB Nijmegen, The Netherlands.
- 2
Centre for Primary Care – University of Manchester, 7th Floor, Williamson Building, Manchester M13 9PL, United Kingdom.