Since January 2023, a total of 8'455 diphtheria cases (2'507 confirmed; 5'948 suspected) and 230 deaths have been recorded in four African countries: Algeria: (80 cases, 10 deaths), Guinea (90 cases, 22 deaths), Niger (272 cases, 8 deaths), and Nigeria (8,013 cases, 190 deaths). Immunization rates in the region are low, and this is in an environment where mining causes large population movements. In addition, the local health system is fragile and has limited resources to respond to this outbreak. Other ongoing outbreaks in the region, particularly pertussis, polio, and rabies, are straining the limited resources available.