Haemophilus ducreyi Bacteria Causing Cutaneous Ulcer Outbreak in Children, Sierra Leone, December 2025

We report a cutaneous ulcer outbreak in Sierra Leone in 2025 that predominantly affected ≈403 schoolchildren. The causative agent was confirmed as Haemophilus ducreyi, a bacterium traditionally associated with the sexually transmitted infection chancroid but more recently recognized as an emerging cause of lower limb cutaneous ulcers in tropical regions.