13 JULY 2026, WASHINGTON, D.C.— Diphtheria is increasing in the Region of the Americas. Between epidemiological week (EW) 1 and EW 21 of 2026, 163 confirmed cases, including five deaths, were reported across three countries: Brazil (n = 2 cases), Haiti (n = 159 cases, including five deaths), and Peru (n = 2 cases). The concentration of cases in Haiti, together with new cases in other countries of the Region, has resulted in a total that already exceeds the annual average of 61 confirmed cases reported across the Americas during 2020–2024. In the context of suboptimal DTP (diphtheria, tetanus, and pertussis) immunization rates, this situation underscores the need to close vaccination gaps, strengthen epidemiological surveillance of vaccine-preventable diseases, and maintain a permanent supply of diphtheria antitoxin (DAT) to control potential outbreaks.