No studies on the arboviral disease risk perception by health professionals
This is the first study on the perception of the present and future risk of vector-borne diseases (i.e., dengue, chikungunya and Zika), in a Western European country, based on an electronic survey completed by French ID physicians in 2016. Many works have focused on disease risk perception in the general population, notably in case of new emerging infectious diseases such as DEN and CHIK [33,34,35,36], H1N1pdm flu [37,38,39] and H5N1 avian flu [40,41,42]; others have focused on general practitioners in France [43,44,45], both general population and practitioners [46], French pharmacists [47] or risk perception in Europe and other countries worldwide [48,49,50]. The appearance of various emerging infectious diseases during the last two decades (e.g., chikungunya, SARS-CoV, MERS-CoV, Ebola virus, Zika), as well as that of antibiotic-resistant bacteria, has stimulated research on risk perception in the general public and policy-makers [51,52,53,54,55]. Information delivered by the media has exacerbated the general feeling, in the public and in national and regional deciders, of the importance of being able to have rapid access to clear information about disease propagation conditions, and to deliver reassuring statements to the population [56, 57]. Conversely, studies on perception risk in the different categories of health professionals, particularly those who directly deal with such diseases and infected patients, are today still very rare, or even absent.
An exploratory study
This was an exploratory study with several important limitations. First, the percentage of responders was small (11.7%). Second, it is possible that the few who responded were more concerned by vector-borne diseases, and this could have introduced a selection bias into our study. Third, we could not compare the responders with all those on the SPILF Discussion List (n = 685) due to missing data, thus preventing any correction for non-responses. This strongly affected the possibility of generalizing our results to the whole community of ID specialists. Nevertheless, we think that these preliminary findings are promising and should stimulate further studies on risk perception within this community.
Environmental, geographical and epidemiological parameters are less influential than expected in explaining disease risk perception in health professionals
Unexpectedly, the many different statistical models used in this study indicated that environmental, geographical and epidemiological explanatory parameters were not as important as professional training, tropical work experience and NPS awareness in explaining present and future disease risk perception in French ID physicians.
Strangely, the presence of tiger mosquitoes in different departments in the south and southwest of France was not retained as an explanatory variable in minimal models, in most cases. Indeed, the perception of arboviral disease risk was, on average, no higher among respondents working in a hospital located in a department colonized by tiger mosquitoes than among those working in the north of France, where this vector species is absent. The variable “presence of tiger mosquitoes” was significant for the analysis of risk perception only at the departmental level and for CHIK, particularly when studying the difference in risk perception between physicians working in the Hérault department where CHIK cases occurred in 2014 [58] and those from all the other departments. The presence of human autochthonous cases of DEN and CHIK during the previous years in different French departments (see Additional file 1: Appendix III) was an explanatory variable for disease risk perception at the department level, but only for Zika (see below). Moreover, like for the presence of tiger mosquitoes, latitude was never an explanatory variable in regression models, thus indicating that disease risk perception by this category of health professionals is not sensitive to a north-south gradient. Conversely, the perception of the risk of DEN, CHIK and ZIKA epidemic spread was higher among respondents working in departments located on or close to the Mediterranean or Gulf of Biscay coasts than among those working in departments close to Germany or Switzerland. Surprisingly, the presence of an international airport in the respondent’s department was not an important explanatory variable for the disease risk perception, except for DEN and ZIKA at the departmental level. This could be explained by the fact that our questionnaire coincided with the onset of the ZIKA epidemic in Latin America [59, 60] and information on ZIKA risk was at that time delivered by the French health authorities to health professionals and travelers on the occasion of the Olympic Games in Brazil, August 2016 [61]. For the year 2016, the World Health Organization also identified major DEN outbreaks in different parts of the world (South America, Philippines, Malaysia, Salomon Islands, Burkina Faso). This could also explain the effect of the ‘presence of human autochthonous cases’ variable on risk perception for ZIKA outbreaks locally. However, this does not explain why the presence of an international airport was not retained as an explanatory parameter for the risk of DEN, CHIK or ZIKA case introduction from abroad.
Professional training, tropical experience and NPS awareness influence disease risk perception by health professionals
Most of the linear models indicated that professional training components (medical school cursus, practical experience and current medicine activities) were often significant variables for explaining disease risk perception in health professionals. Having an infectiology or additional training specialty (e.g., travel medicine, epidemiology) strongly influenced their answers in minimizing their perception of arboviral disease risk. This was particularly true for the estimation of imported case risk at the departmental level, and the perception of autochthonous case and epidemic risk at the national level. Moreover, professional experience in tropical regions was an important parameter for explaining perception of arboviral disease risk in mainland France, with generally a lower level of risk perception for respondents with tropical healthcare experience. Many French practitioners traditionally spend time in French overseas territories and developing countries during and after their medical studies. NPS awareness in mainland France was also an important parameter, notably for the imported case scenarios at the departmental and national levels. Undoubtedly, knowledge of the information delivered by the NPS on local disease surveillance and diagnostic practices made respondents more aware of the real situation and lowered the perception of arboviral disease risk compared with ID physicians not aware of the plan. Thus, NPS awareness tended to make respondents more confident about their perception of risk and homogenized the questionnaire responses towards lower risk levels.
Age and year of medical degree may interact with training components
In some linear models (Table 2), the respondent’s birth year and year of medical degree and their two-way interaction terms with infectiology specialization or with NPS awareness also were important explanatory factors for disease risk perceptions. In particular, the year of medical degree was retained in the regressive models for the perception of imported case risk and, to a lesser extent, of the epidemic risk at both departmental and national levels. The importance of the birth year and year of medical degree suggests that ID physicians of different graduating classes could have received different specialized training on arboviral diseases, with older doctors giving generally lower scores. Alternatively, the younger generations of practitioners are more sensitive to emerging threats due to the recurrence of these events in the last 2 to 3 decades and their significant media coverage. In addition, the two interaction terms birth year×infectiology specialization and birth year×NPS indicated that health professionals without infectiology specialization and who were born in or after 1972 tended to give higher scores (p < 0.0001) than the rest of the responders, and that those without NPS awareness and born in or after 1972 tended to give lower scores (p < 0.0001). Overall, this suggests that the initial university training strongly impacts current training and professional awareness on risk perception.
Risk perception is low for sporadic cases but high for epidemics
The dispersion of the values for future sporadic cases (Figs. 1a and 2) suggests that although respondents perceived the current risk of arboviral diseases in mainland France as very low, they imagined all plausible scenarios for future sporadic case risk (from very low to high). Moreover, for higher perception values of current sporadic case risk, the values for future risk tended to converge towards low to medium estimates for the three arboviral diseases and the two scales (see Fig. 1). Nevertheless, we are conscious that a considerable reluctance to extrapolate about the future may exist when “nothing or near nothing” can be perceived today. On the other hand, the future disease risk perception values (Fig. 1b) tended to increase with the increase of the present risk perception values. Two clear patterns of arboviral disease risk perception in mainland France appeared in this study: i) respondents tended to weigh down the future risk of DEN, CHIK and ZIKA sporadic cases in a context of major uncertainty; and ii) they estimated a high level of future epidemic risk. These differences could be explained by the fact that specialists consider themselves and the national authorities effective in controlling the appearance and spread of sporadic disease cases, whereas they see as more limited their capacities to control an epidemic. In addition, for the epidemic scenario, the three diseases were pooled together. Consequently, the responders gave a global response, but were not able to qualify the type of risk: an epidemic could happen in the future whatever its etiological origin.
Interestingly, several recent models on risk of ZIKA outbreaks in the US, based on vector ecology, have suggested disease spread outside of the southernmost counties, a prediction that is inconsistent with actual observations of the ZIKA epidemic on the continent thus far [30, 33]. The findings that we present here are consistent, and would tend to indicate that ID physician perception and its variability (age of training, tropical experience…) of emerging arboviral disease threats may be an important component to be considered in regional and global health security.