Determinants of physician attitudes towards the new selective measles vaccine mandate in Germany

In March 2020, as part of the Measles Protection Act, a new mandatory policy on measles vaccination came into effect in Germany, requiring proof of measles immunization for all children and staff in childcare and schools, as well as health workers [1]. If individuals are not able to provide this proof, a variety of sanctions can be implemented: access to pre-school childcare can be rejected, at school penalties up to EUR 2500 can be collected, new employment can be rejected, and employees can be deployed elsewhere. Exemptions exist for individuals with proof of naturally-acquired immunity or with medical contraindications, e.g., allergy to vaccine components. The level of enforcement of the mandate has yet to be evaluated. This is the first vaccine mandate to be implemented in Germany, at least when only considering the last decades. Historically, there have been vaccine mandates, in the 19th and beginning of the twentieth century, against smallpox and in the German Democratic Republic against a variety of diseases.

In the context of the 2018 European Council recommendation to take action against vaccine hesitancy [2], the World Health Organization (WHO) listing vaccine hesitancy as one of the ten threats to global health in 2019 [3], large outbreaks of measles in Germany and the European region [4], and new mandates in Italy [5] and France [6], discussion evolved regarding a mandatory measles vaccination policy in Germany. In the winter of 2019, the Measles Protection Act passed in the German parliament with several measures to improve the immunization system in Germany, including new regulations on disease notifications, submission of physician claims data to be included in an immunization information system, and the obligation to provide a proof of measles protection of children and specific professional groups.

Physicians in private practices have a key role in implementing this law in Germany. First and foremost, they are the ones who primarily provide vaccines to the child and adult populations in Germany and counsel patients on vaccines. Among private physicians, the main vaccine providers are pediatricians, general practitioners (GPs), internists, and gynecologists. Pediatricians provide vaccines mainly to children, while GPs, internists and gynecologists provide vaccines mainly to adults. Secondly, they are obliged by the new law to ensure that their staff is protected against measles as well. And lastly, they themselves are obliged to be vaccinated, if not born before 1970 or protected by naturally-acquired immunity. Hence, with regard to implementation, the legislator depends on provider cooperation in these three important ways. The Measles Protection Act changes the context in which physicians operate as vaccine providers. Understanding physician attitudes towards mandates is crucial if we want to understand how physicians will implement the mandate and how the mandate may affect other vaccine decisions [7]. In particular, concerns were raised that the mandate may evoke reactance among physicians who might in turn be less likely to recommend other voluntary vaccines to their patients [8].

Physicians differ in attitude towards vaccinations and these differences affect their recommendations and vaccination behaviors [9, 10]. In addition, physicians might differ in their attitudes towards mandates. A mandate drastically reduces free choice regarding vaccination decisions for their patients, their staff, and themselves. Physicians, who formerly had the task to convince patients of measles vaccination, can now refer to the mandate. This might make it easier for those who did not feel confident before in their ability to talk to patients about the vaccines and explain their value. It might also relieve physicians who face many vaccine-hesitant patients, as they can now refer to the mandate. Mandates can also set new social norms or foster pre-existing norms, thus interacting with physician attitudes towards vaccines [8]. Physicians base their own vaccine decisions, and to some extent, their vaccine recommendations, on their own confidence in vaccines and the system that delivers them, their collective responsibility (willingness to protect others), constraints (perceived barriers), complacency (not perceiving diseases as a high risk), and calculation (engagement in extensive information search). These 5C psychological determinants of vaccination behavior [11] might also be associated with physician endorsement of vaccine mandates.

We conducted a national survey among private physicians in Germany shortly before the mandate became effective. Based on the above-mentioned considerations, we first explored whether physician attitude to the mandate was associated with the 5C psychological determinants of vaccination behavior. Secondly, we explored whether communication self-efficacy and patient clientele, as well as the expected consequences of the mandate, would be associated with attitude towards the mandate.

The Measles Protection Act was initiated by the Ministry of Health in May 2019 in a political and societal climate of broad acknowledgement that something had to be done to strengthen the national immunization program and to fight vaccine hesitancy in Germany [17]. Former plans to eliminate measles by 2015 had failed [18]. Vaccination coverage for children was high (> 95% MCV1), but vaccination was often delayed and incomplete [19]. Furthermore, considerable vaccination gaps were identified among young adults (80% coverage for adults aged 18–29 years, 47% for those aged 30–39 years) [20]. A mandate was considered to be one option among others to increase vaccine uptake and as such both the governing parties and medical societies as well as other stakeholders supported it [21‐23]. Some stakeholders, however, expressed concerns regarding the legal, sociological and ethical dimension of such a mandate, e.g. the German Ethics Council [24]. Moreover, potential psychological consequences were discussed, such as detrimental effects on the willingness to vaccinate against diseases where vaccination remained voluntary [25‐27]. The result of the controversy was a law that encompassed - beyond a mandate - different aspects to strengthen the immunization system in Germany [1]. This study aimed at understanding physicians’ attitudes towards vaccine mandates shortly before the introduction of the law.

A large majority of the private physicians who participated in our survey were in favor of the new measles vaccination mandate and had a positive attitude towards vaccine mandates in general. However, pediatricians, i.e., those physicians who primarily vaccinate children against measles, were less in favor of a measles vaccine mandate compared to other physician subgroups. The more participants expected negative consequences of the mandate for their own practice, e.g., more work or a burden for patient-provider relationships, the more they had negative attitudes towards mandates.

We assumed that physicians who regularly encountered difficulties in vaccine counseling would have a positive attitude towards the mandate, as the mandate might eliminate their role in discussing the rationale for the measles vaccine. However, in our study, we observed the contrary. Physicians had a more negative attitude towards the mandate when they had lower confidence in communicating with patients about vaccines, i.e., lower communication self-efficacy and a lower proportion of unquestioning acceptors among their patients. In contrast, physicians who felt higher communication self-efficacy and who had more unquestioning acceptors among their patient clientele were more likely to endorse vaccine mandates.

Among the psychological determinants, a more negative attitude towards the mandate was associated with lower vaccine confidence, lower collective responsibility, higher complacency, and higher calculation, while no effect was found for constraints. With regard to confidence, we assume that when physicians question vaccine safety, mandatory vaccines appear worrisome, as vaccination may put the vaccinated person at risk for potentially adverse events. From an ethical perspective, a mandate violates individual liberty, i.e., free will, but this violation may be justified as long as the mandate maximizes individual health. Those who lack confidence in vaccine safety, however, may question this benefit to individual health [28]. Likewise, a French study conducted shortly before the implementation of new vaccine mandates in France found fear of side-effects to be associated with a more negative attitude towards mandates among the general population [29]. In an Italian study pregnant women were more likely to favor vaccine mandates when they felt that health professionals were honest to them about the risk of vaccines [30]. With regard to collective responsibility, we believe that physicians who vaccinate themselves and others in order to protect others could favor a mandate, because a mandate restricts individual liberty in order to protect others. In contrast, physicians who vaccinate for self-protection only (low collective responsibility) will be more willing to take advantage when enough others are vaccinated and thus, might oppose a mandate, as their personal risk of infection is relatively low [31]. In accordance with this, an Australian study among health care workers found that the protection of co-workers was among the primary reasons for supporting an influenza vaccine mandate [32]. With regard to complacency, we suggest that when risk perception is high enough, more drastic measures seem acceptable. The above-mentioned French study found that the perception that vaccines bring important health benefits was associated with a more positive attitude towards mandates [29]. In our study, participants with high calculation were more likely to have a negative attitude towards vaccine mandates. Individuals with high calculation base their decisions on utility maximization, i.e., engaging in extensive information seeking and attempting to make the best decision for themselves [8]. In previous studies, it was shown that calculation is associated with non-vaccination [11]. Physicians high on calculation might see their freedom to take these selfish, rational decisions infringed by a vaccination mandate [26].

Pediatricians had more negative attitudes towards vaccine mandates (especially mandates for children) than other physician subgroups. Pediatricians were also less confident that more children would be vaccinated due to the mandate than other physician subgroups. Thus, those physicians who have the most experience in vaccinating children were less in favor of a measles mandate for children and less convinced it would successfully increase coverage. We found that not being a pediatrician increased the perception that more children would be vaccinated (expected consequence), which in turn increased a positive attitude towards mandates (mediation effect). At the same time, pediatricians were better informed about vaccine safety (vaccine knowledge), and had a higher communication self-efficacy and more unquestioning acceptors among their patients.

Some limitations of our study need to be acknowledged. The survey does not control for social desirability. The survey was conducted, among others, on behalf of the national public health authority in Germany, which might have enhanced social desirability, possibly leading to an overestimation of a favorable attitude towards vaccine mandates and vaccines, in general. Since it is unknown how many physicians we reached with questionnaires (mixed-mode online/offline), we were not able to calculate a response rate. There might be a selection bias in that those more engaged in the topic, either pro-vaccine or vaccine hesitant, might have been more likely to participate. By incentivizing participation through a lottery, we tried to encourage participation and reduce selection bias. Due to our study design we were unable to determine whether our survey population is representative of Germany’s primary care providers. We could show, however, that the distribution of gender and region in our study population was similar to the distribution of gender and region among physicians in Germany (Supplementary Table 2) [33]. Furthermore, the means for the 5C psychological determinants of vaccination in our study (GPs only) were very similar to a comparable study among German family physicians which used random sampling (data collection 2017/18) [34].

There are few studies that evaluate determinants of attitudes towards vaccine mandates [35, 36]. A systematic review on attitudes towards vaccine mandates found varying degrees of approval of vaccine mandates in different countries and different populations. However, the authors conclude that few studies go beyond a mere description of approval rates to the respective mandates and suggest that further studies should investigate the determinants of attitudes towards mandates [37]. Our study contributes to filling this knowledge gaps. A follow-up study is planned for 2022 to assess whether physician attitudes towards vaccine mandates have changed and whether expected consequences occurred. As part of a larger research project evaluating the measles vaccine mandate in Germany, a longitudinal survey study among parents has been initiated in August 2020.

Shortly before the introduction of a measles vaccine mandate in Germany, the majority of physicians were in favor of the mandate and vaccine mandates, in general. The attitudes, however, differed. This study identified determinants of these attitudes and hence has implications for policy and further research:

Pediatricians, even though well-versed vaccine providers, were more hesitant towards the mandates, especially for the group of patients they serve – children. Their lack of confidence in the ability of the mandate to increase vaccine coverage among children explains their hesitancy towards mandates. Given their high expertise as vaccine providers, their concern deserves further investigation. Evaluation of the vaccine mandate and its effects on vaccine uptake and vaccine hesitancy is needed - not only for this reason - to enable an evidence-based discussion. This includes investigation into other tools used by pediatricians to increase vaccine uptake (e.g. reminder systems).

In addition, negative attitudes on mandates occur among physicians with lower communication self-efficacy and higher numbers of vaccine hesitant patients. Therefore, physicians need adequate support to communicate well with patients, especially hesitant patients. This includes offering training for physicians in doctor-patient conversation, e.g. applying promising techniques such as motivational interviewing [38], and making vaccination more prominent in medical training at university.

Our study suggests that physicians who have low confidence in vaccination, low collective responsibility and high complacency have a more negative attitude towards mandates, and might react with anger, similar to an effect observed in patients [26, 27]. It remains unclear which consequences anger could have on both physicians and patients. Public health institutions can try to prevent anger by communicating herd protection, thus countering detrimental effects of vaccine mandates, e.g., lower vaccine uptake for other voluntary vaccines [27]. This means that– in all communication activities - vaccination is framed as a collective responsibility, elimination of measles as a common effort, and vaccination as a way to protect those who cannot protect themselves [39]. Furthermore, public health institutions should invest more in transparency concerning vaccine safety and effective communication of the risks of vaccine-preventable diseases, e.g., the resurgence of measles, if they want to maintain physician support in vaccine mandates. This involves making vaccine safety monitoring data more accessible to laypersons, and debunking vaccine safety myths [40].

Whether or not mandates are effective in increasing measles vaccine uptake in Germany is yet to be evaluated. Omer et al. have argued that mandates can be effective if implemented with care and consideration of context [25]. Physician support of mandates, however, cannot be taken for granted.