Prevalence of Tick-borne Encephalitis in the Pediatric Population Treated at the HUS and Characterization of Confirmed Pediatric Cases

Tick-borne encephalitis (TBE) is a zoonosis mainly transmitted to humans by the bite of ticks of the genus Ixodes and, to a lesser extent, by the consumption of contaminated and unpasteurized dairy products. During the last decade, the epidemiology of this arbovirosis has changed profoundly with the discovery of new human cases and/or new areas of circulation of tick-borne encephalitis virus (TBEV) throughout Europe and particularly in France. Historically, Alsace is the main endemic area for this pathology in France. The pathology is notifiable since June 2021 in France. Although TBEV infection in children seems to lead to a milder clinical presentation, data are much less abundant than in adults and only a few cases reported in infants under 1 year old have been published. Data from the most recent ECDC Annual Epidemiological Report on TBE (2019) showed incidence rates of approximately 0.2 and 0.5 per 100,000 population in patients younger than 5 and 15 years, respectively. However, several observations may moderate and challenge both the low incidence rate and the less severe clinical presentation reported in children