Emergence of Erythromycin-Resistant and Pertactin- and Filamentous Hemagglutinin-Deficient Bordetella pertussis Strains - Beijing, China, 2022-2023.

What is already known about this topic?:Pertussis has reemerged as a significant public health threat, primarily due to variations in Bordetella pertussis strains, antimicrobial resistance, and vaccine evasion. What is added by this report?:All isolated strains were identified as ptxA1/ptxC2/ptxP3/prn150/fim2-1/fim3-1/fhaB1/tcfA2 type and exhibited resistance to erythromycin. Two strains showed a deficiency in Fha, thirty in Prn, and one strain exhibited multiple immunogen deficiencies. What are the implications for public health practice?:The emergence and spread of immunogen-deficient strains likely result from prolonged vaccine selection pressure, posing challenges to the efficacy of pertussis vaccines. Additionally, the ongoing dissemination of ptxP3 strains with high-level macrolide resistance presents a significant obstacle to clinical treatment strategies.