en 25215182 Background: Re-emergence of pertussis has been reported in Iran despite a high rate of vaccination coverage. Low efficacy of the vaccine might be due to the genetic divergence between clinical versus vaccine strains. In the current study, the genetic profiles of clinical isolates and vaccine strains of Bordetella pertussis (B. pertussis) were assessed by using Pulsed Field Gel Electrophoresis (PFGE). Methods: Following phenotypic and molecular identification of isolates, XbaI-digested genomic DNA of 5 clinical isolates, 2 vaccine strains and a Tohama I strain were analyzed by PFGE along with B. parapertussis as a control. Results: Seven distinct PFGE profiles were found among all examined isolates/strains. In 5 clinical isolates, 4 profiles were identified whereas the vaccine strains displayed 2 distinct profiles. The reference strain, Tohama I had a distinct profile. Vaccine and clinical profiles had low similarity, with relatedness of approximately 40%. Conclusion: The genetic profiles of B. pertussis were different between circulating isolates and vaccine strains used in the national vaccination programs. Since new genetic profiles of B. pertussis can be disseminated periodically, the profiles of isolates circulating in the population should be monitored over the course of the re-emergence. Bordetella pertussis, PFGE profile, Vaccination, Whooping cough 178 184 https://www.ajmb.org/En/Article.aspx?id=183 https://www.ajmb.org/PDF/En/FullText/183.pdf FaezehHaghighiDivision of Microbiology, Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran774FereshtehShahcheraghiDepartment of Bacteriology and Microbiology, Pasteur Institute of Iran, Tehran, Iran775EbrahimAbbasiDepartment of Bacterial Vaccines, Razi Vaccine and Serum Research Institute, Karaj, Iran776Seyed SaeedEshraghiDivision of Microbiology, Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran777HojjatZeraatiDepartment of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran778Seyed Ali JavadMousaviDepartment of Pulmonology, Hazrat Rasool Hospital, Iran University of Medical Sciences, Tehran, Iran779HosseinAsgarian-OmranDepartment of Immunology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran238MasoumehDouraghiDivision of Microbiology, Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran781FazelShokriMonoclonal Antibody Research Center, Avicenna Research Institute, ACECR, Tehran, Iran5