High Prevalence of Macrolide-Resistant Bordetella pertussis and ptxP1 Genotype, Mainland China, 2014–2016

• Main Authors: Lijun Li, Jikui Deng, Xiang Ma, Kai Zhou, Qinghong Meng, Lin Yuan, Wei Shi, Qing Wang, Yue Li, Kaihu Yao
• Format: Article
• Language: English
• Published: Centers for Disease Control and Prevention 2019-12-01
• Series: Emerging Infectious Diseases
• Subjects: Bordetella pertussis; antibiotic sensitivity; antimicrobial sensitivity; macrolide resistance; virulence-related genotype; ptxP1
• Online Access: https://wwwnc.cdc.gov/eid/article/25/12/18-1836_article

According to the government of China, reported cases of pertussis have increased remarkably and are still increasing. To determine the genetic relatedness of Bordetella pertussis strains, we compared multilocus variable-number tandem-repeat analysis (MLVA) results for isolates from China with those from Western countries. Among 335 isolates from China, the most common virulence-associated genotype was ptxA1/ptxC1/ptxP1/prn1/fim2–1/fim3A/tcfA2, which was more frequent among isolates from northern than southern China. Isolates of this genotype were highly resistant to erythromycin. We identified 36 ptxP3 strains mainly harboring ptxA1 and prn2 (35/36); ptxP3 strains were sensitive to erythromycin and were less frequently from northern China. For all isolates, the sulfamethoxazole/trimethoprim MIC was low, indicating that this drug should be recommended for patients infected with erythromycin-resistant B. pertussis. MLVA of 150 clinical isolates identified 13 MLVA types, including 3 predominant types. Our results show that isolates circulating in China differ from those in Western countries.