The persistence of vaccine-preventable diseases and the resurgence of measles in Europe in 2017 and 2018 are a result of immunization program performance gaps, and sub-optimal vaccination acceptance and demand.1 European immunization programs, despite having the resources and means to equitably deliver high-quality immunization services to the entire population of Europe, are failing in their ability to close immunity gaps and sustain high demand for vaccination. Failures can be identified on the quality of training and education of frontline healthcare providers (ie, those who vaccinate and immunization program managers) on immunology, vaccinology, risk-benefit ratio, safety, and the true impact of vaccines in the society.
Immunization service quality is considered a key driver of vaccination demand and is a significant factor in determining any programs ability to tackle vaccination hesitancy—this includes the capacity of healthcare providers and their level of confidence to promote and administer vaccines. Their knowledge and attitudes influence the vaccination confidence of caregivers.2 Studies have shown that healthcare providers are the definitive source for immunization-related questions and the most trusted source by most caregivers of infants.3 However, many vaccinators, although supportive of routine national immunization schedules and programs, have a low level of knowledge on vaccines and vaccine safety—which contributes to the declining vaccine confidence in the population and results in vaccinators falsely contraindicating immunization.4
False contraindications have been identified as one of the primary reasons for under-vaccination of children in the world.5 During an immunization session, some scheduled shots are intentionally delayed or withheld due to erroneous judgment of a contraindication, or a misperceived harm stemming from the doubts carried by healthcare providers. This has a direct impact on the immunization coverage and indirectly contributes to vaccine hesitancy among caregivers, creating a false safety concern. In 2017, the European Technical and Advisory Group of Experts recognized this problem and recommended that the World Health Organization (WHO) Regional Office for Europe took action to understand more about the issue and develop an action plan to address this.6
In this article, we present the results of a survey that aimed to determine how frequent false vaccine contraindication assessments are among European healthcare providers—based on their levels of knowledge. The results of this study could be used to develop and adapt training materials, and to tailor other educational interventions targeting healthcare providers.
A survey was conducted among members of the European Society of Pediatric Infectious Diseases (ESPID; www.espid.org), in June 2018. The survey’s purpose was to assess the knowledge of vaccinators on contraindications for immunization. Ten10 scenarios were presented to which the healthcare providers had to determine whether to vaccinate, to delay, or to hold (due to contraindication) immunization. The themes covered were fever, epilepsy, cerebral palsy, antibiotic-use, recent chemotherapy, anaphylaxis, breast-feeding, steroid-use, and convalescent state. The questionnaire was electronically distributed using ESPID distribution channels and was made available for 20 days online. A feedback was given as a plenary lecture on the 2018 ESPID Annual Meeting held in Malmo, Sweden.
We excluded from the analysis respondents outside the Member States of WHO European region. We also excluded nonclinical members of ESPID, namely (but not limited to) project managers, administrative assistants, basic biologists, and laboratory scientists.
The study was approved by the Research and Networking Committee of the ESPID. The respondents were made aware of the nature of the research. Any identification information was not collected, and the confidentiality of the respondents were ensured. Participation was voluntary.
Of 998 ESPID members who participated, we analyzed the responses of 573 European healthcare providers (57.4%), of which 538 (93.9%) were employed in general pediatrics or infectious diseases practice. The remaining 35 respondents (6.1%) were general physicians, public health practitioners, nurses, and other medical specialists. Majority of the respondents came from High-income countries (95.5%, classification based on World Bank income classification), and from Southern European Region (67.7%, classification based on UN Statistical Division). A nonresponse rate of 10.2% (mean) was observed, with a total of 5704 valid responses to case scenarios from each respondent.
Among all responses, 21.9% (1114/5074) of the answers were wrong: 21.4% (877/4096) of scenarios would have been postponed or contraindicated to vaccination, and 24.2% (237/978) of respondents would vaccinate the patient, despite the existence of a true contraindication or reason to delay vaccination (Table 1).
A large proportion of respondents would delay vaccinating infants with fever (75.7%, 389/514) (Table 1). Although the majority would vaccinate, there is a sizable proportion of vaccinators who would delay immunization in patients on antibiotics (37.5 %, 192/512) and steroid medication at (33.1%, 171/516), respectively. Vaccination should be delayed in persons who recently underwent chemotherapy; however 4.6% (23/500) of respondents would continue with the scheduled shots, and only 34.4% (172/500) would not offer immunization. Only 6.4% (33/573) of the respondents correctly answered all the case scenarios.
Missed opportunities on vaccinations happen when a child with no contraindication does not receive vaccines, which may account for up to 32% of all clinic visits.7 False contraindications or unnecessary delays in vaccination may occur among European healthcare providers more frequently than expected, which significantly contributes to missed opportunities to vaccinate.
Healthcare providers often refuse to immunize a child with mild illness or fever in the clinic, despite no evidence of being considered a vaccine contraindication. In this study, fever is one of the most commonly misconstrued scenarios in which healthcare providers delay or withhold immunization for patients. Several guidelines have all recognized the option of delaying immunization in persons suffering from severe illness, to avoid falsely attributing the clinical deterioration to the vaccines.8 However, there are no strict clinical criteria on immunization deferrals, or guidelines on vaccination upon the period of convalescence. The absence of clear-cut guidelines may have resulted in using individualized criteria, which may have led to the wide disparity in the implementation of immunization.
Antibiotic- and steroid-use were common reasons for delaying immunizations in children. Although standard guidelines are in place for continuing the immunization schedule in persons using antibiotics (with an infection) and/or using steroids, the survey found that a significant proportion of healthcare providers may be misinformed or unaware of the guidelines. It is generally accepted that ongoing infection and antibiotic-use had no effect on vaccine immunogenicity, nor did it lead to any adverse effect. Similarly, low-dose (prednisolone equivalent of <2 mg/kg/d or <20 mg/d) and short-term (<14 day) steroid-use is not a reason to delay immunization.
A significant number of respondents incorrectly labeled postchemotherapy as an absolute contraindication. However, live vaccines are safe for use in leukemia, lymphoma and other hematologic malignancies in remission, and 3 months after chemotherapy. Although many existing guidelines have been clear on these clinical cases, there seems to be a number of vaccinators that still have misperceptions or are unaware of these recommendations.9 Thirty-four percent of vaccinators have overestimated the risk in vaccinating a child who underwent chemotherapy, which outweighed the expected benefit.
We identified several limitations that may affect the interpretation of the results. First, there was no formal assessment of the baseline knowledge of vaccines and the level of vaccine confidence in the study participants. Our respondents may represent a group of vaccinators with higher level of knowledge on immunization owing to their interest in attending a scientific conference in the field of infectious diseases. Thus, the proportion of healthcare providers with misperceptions on contraindications may be larger among frontline healthcare providers, since many studies find poor knowledge among healthcare providers on vaccines and immunization. Second, attitudes and practices on immunization were not investigated. Some literature suggests a disparity between healthcare provider’s knowledge, attitudes, and practices.3,10 There are various factor that determines this disparity. Current literature suggests that studies should be conducted to elucidate this phenomenon further. Finally, immunization practices and protocols in different countries should also be reviewed, to exclude that no false contraindications, exposed by this survey, are included in the authorized guidelines in the respective place/country of practice. Such an analysis might improve our understanding of the reasons behind the vaccinators’ response to the questionnaire.
In an era of declining immunization coverage and eroding vaccine confidence in Europe, the education and training of frontline on vaccines and vaccine safety are crucial in promoting its use. Several studies have already shown that healthcare providers are the most trusted source of advice for most parents when deciding whether to vaccinate their children.3 Healthcare providers’ knowledge and attitudes considerably affect a parents’ intention to vaccinate. Thus, increasing the level of expertise of vaccinators on immunization and vaccine safety will enable frontline healthcare providers to be more confident in their respective place of practice. In turn, training healthcare providers on vaccine safety and false contraindications may directly decrease the missed opportunities for vaccination in children, and furthermore, increase immunization coverage in Europe.
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6. 16th Meeting of the European Technical Advisory Group of Experts on Immunization
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and False Contraindication to Vaccination: Training Manual. 2017.Copenhagen, Denmark: WHO Regional Office for Europe.
10. Agrinier N, Le Maréchal M, Fressard L, et al. Discrepancies between general practitioners’ vaccination recommendations for their patients and practices for their children. Clin Microbiol Infect. 2017;23:311–317.