Ongoing toxin-positive diphtheria outbreaks in a federal asylum centre in Switzerland, analysis July to September 2022
Jacob Kofler, Alban Ramette, Patricia Iseli, Lea Stauber, Jens Fichtner, Sara Droz, Annina Zihler Berner, Anna Bettina Meier, Michelle Begert, Sabine Negri, Anne Jachmann, Peter M. Keller, Cornelia Staehelin, Barbara Grützmacher
Abstract
Two diphtheria outbreaks occurred in a Swiss asylum center from July to October 2022, one is still ongoing. Outbreaks mainly involved minors and included six symptomatic respiratory diphtheria cases requiring antitoxin. Phylogenomic analyses showed evidence of imported and local transmissions of toxigenic strains in respiratory and skin lesion samples. Given the number of cases (n = 20) and the large genetic diversity accumulating in one centre, increased awareness and changes in public health measures are required to prevent and control diphtheria outbreaks.