Key Points

In 2021, the overall annual incidence of pediatric HUS was lower than that observed over the past four years.

Although this decrease in annual incidence is observed among children under three years of age, the incidence in this age group remains high and significantly higher than that observed among older children. As in previous years, regional variation is observed. In 2021, the Bourgogne-Franche-Comté and Auvergne-Rhône-Alpes regions were particularly affected.

In 2021, serogroup O26 remained the most prevalent, followed by serogroup O80. After several years of decline in the proportion of cases caused by O157, a slight increase in the number of O157 strains was observed in 2021.