[Taking origins into account in medical reasoning in infectious and tropical diseases? A critical look]. / Tenir compte des origines dans le raisonnement médical en maladies infectieuses et tropicales ? Un regard critique.

Healthcare discriminations based on one's ethnic background is increasingly being studied in medicine. The scale of the Covid-19 pandemic has played an important role in bringing them to light. Data, although scarce, exist in France. These discriminations have an impact on the care pathway and contribute to the renunciation of care by the most affected populations. The issue of discrimination is particularly relevant in infectious diseases. Although the epidemiology of infectious diseases is unevenly distributed worldwide, erroneous social representations are prevalent and expose to a harmful prejudice against migrants with regard to infectious diseases. The transmissible nature of some infectious diseases reinforces their stigmatizing potential. In this context, it seems important to discuss the dimension to be given to social determinants, geographical origin, phenotype, and ethnicity in teaching and medical reasoning. The English-speaking world uses the concept of "race" in a structural way, whereas this "international standard" has not been applied in France until now. To improve the care of people from minority groups, it seems important to better document and teach a more nuanced clinical reasoning based on origin, without neglecting the importance of collecting and taking into account social determinants of health and environmental factors.

[Dengue vaccines, a time for cautious optimism?] / Vaccins contre la dengue, le temps de l'optimisme prudent ?

Vaccine could take a central role in the strategy to reduce the burden of dengue. The development of an effective and safe vaccine must address various immunological challenges. Several vaccines are currently in development. To date, two live-attenuated vaccines have been deployed. Both have an effectiveness that varies depending on the serotypes. The deployment of the Dengvaxia vaccine, which began in 2015, was marked by a major safety alert leading to its use being restricted to previously dengue-seropositive people over 9 years old. The Qdenga vaccine is currently being deployed. There is for now insufficient data to ensure its safety in seronegative people. Some travelers, who have previously been infected with dengue, are a group for whom a vaccination recommendation applies.

Les vaccins pourraient occuper une place centrale dans la stratégie de réduction du fardeau de la dengue. Le développement d'un vaccin efficace et sûr est complexe car il doit relever plusieurs défis immunologiques. Différents vaccins sont en développement. À ce jour, deux vaccins vivants atténués ont été déployés. Tous deux ont une efficacité qui varie selon les sérotypes. Le déploiement du vaccin Dengvaxia, débuté en 2015, a été marqué par une alerte de sécurité majeure conduisant à restreindre son usage aux personnes de plus de 9 ans, préalablement séropositives pour la dengue. Le vaccin Qdenga est en cours de déploiement. Le recul est insuffisant pour assurer son innocuité chez les séronégatifs. Certains voyageurs, ayant déjà été infectés par la dengue, constituent un groupe pour lequel une recommandation vaccinale s'applique.

[Dengue fever is knocking on the doors of Europe]. / La dengue frappe aux portes de l'Europe.

Dengue is a subject of major concern in global health because its incidence is increasing, and its geographical area continues to expand. On a global scale, the projections available point in the direction of an extension of the geographical areas of the Aedes vectors, partly in connection with the increase in temperatures and the modification of precipitation cycles in the context of the climate change. This expansion is expected at the borders of the areas of current spread with, however, a possible contraction in certain areas that are now endemic. In Europe, the threat of a dengue epidemic outbreak now exists. It is on this continent that the number of new exposures in immunologically naïve people is likely to be the greatest in the near future.

La dengue est un sujet de préoccupation majeure en santé globale car son incidence augmente et son aire géographique ne cesse de s'étendre. À l'échelle globale, les projections dont on dispose vont dans le sens d'une extension des zones géographiques des vecteurs Aedes, en lien en partie avec l'augmentation des températures et la modification des cycles de précipitation dans le contexte du changement climatique. Cette expansion est attendue aux frontières des zones de diffusion actuelle avec toutefois une contraction possible dans certaines zones aujourd'hui endémiques. En Europe, la menace d'une flambée épidémique de dengue existe désormais. C'est sur ce continent que le nombre de nouvelles expositions chez des personnes immunologiquement naïves risque d'être le plus important dans un avenir proche.