Key Points

• In 2016, 55 cases were reported in Normandy; this number remained stable compared to 2015 and was higher than in 2014.

• One of the lowest regional incidence rates in mainland France.

• Case characteristics were identical to those observed at the national level.

• A marked increase in the number of isolated strains, providing data to clarify the clustered nature of the cases and identify the source of contamination (25%).