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Fu P, Li Y, Qin J, Xie L, Yang C, Wang C. Molecular epidemiology and genomic features of Bordetella parapertussis in Shanghai, China, 2017-2022. Front Microbiol 2024; 15:1428766. [PMID: 39044958 PMCID: PMC11263204 DOI: 10.3389/fmicb.2024.1428766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2024] [Accepted: 06/28/2024] [Indexed: 07/25/2024] Open
Abstract
Background Pertussis is a highly contagious respiratory illness mainly caused by Bordetella pertussis (BP). Bordetella parapertussis (BPP) can induce symptoms compatible with pertussis, but has been underdiagnosed and underreported. The current pertussis vaccines offer low protection against BPP. Herein, we aim to reveal the epidemiology and genomic evolution of BPP in Shanghai, China. Methods Children diagnosed with BPP infection from January 2017 to December 2022 in Shanghai, China were enrolled. We performed antimicrobial susceptibility testing (AST), multiple locus variable-number tandem repeat analysis (MLVA), and whole genome sequencing (WGS) analysis. A total of 260 international BPP genomes were chosen for comparison to investigate the genomic diversity and phylogenetic characteristics of Chinese strains within a global context. Results Sixty patients were diagnosed with BPP infection by culture, with the positive ratio of 3.5‰ (60/17337) for BPP in nasopharyngeal swap samples. The average age of patients was 4.5 ± 0.3 years. BPPs contained four MLVA types including MT6 (65.0%), MT4 (26.7%), untype-1 (6.7%) and MT5 (1.7%), and none of strains showed resistance to macrolides. All strains carried virulence genotype of ptxP37/ptxA13/ptxB3/ptxC3/ptxD3/ptxE3/fim2-2/fim3-10. MT4 and MT5 strains carried prn54, whereas MT6 and untype-1 BPPs expressed prn101. We identified two outbreaks after 2020 caused by MT4 and MT6 strains, each corresponding to distinct WGS-based phylogenetic lineages. The MT4-lineage is estimated to have originated around 1991 and has since spread globally, being introduced to China between 2005 and 2010. In contrast, the MT6-lineage was exclusively identified in China and is inferred to have originated around 2002. Conclusion We revealed the genomic diversity of BPPs circulating in Shanghai, China, and reported the outbreaks of MT6 and MT4 BPPs after 2020. This is the first report on the emergence and regional outbreak of MT6 BPPs in the world, indicating that continuous surveillance on BPPs are thus required.
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Affiliation(s)
- Pan Fu
- Laboratory of Microbiology, Department of Clinical Laboratory, Children’s Hospital of Fudan University, National Children's Medical Center, Shanghai, China
- Nosocomial Infection Control Department, Children’s Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Yijia Li
- Laboratory of Microbiology, Department of Clinical Laboratory, Children’s Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Jie Qin
- Laboratory of Microbiology, Department of Clinical Laboratory, Children’s Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Li Xie
- CAS Key Laboratory of Molecular Virology and Immunology, The Center for Microbes, Development and Health, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai, China
| | - Chao Yang
- CAS Key Laboratory of Molecular Virology and Immunology, The Center for Microbes, Development and Health, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai, China
| | - Chuanqing Wang
- Laboratory of Microbiology, Department of Clinical Laboratory, Children’s Hospital of Fudan University, National Children's Medical Center, Shanghai, China
- Nosocomial Infection Control Department, Children’s Hospital of Fudan University, National Children's Medical Center, Shanghai, China
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de Paula VG, de Sousa RS, da Silva RCMR, Alves EG, Caetano AR, Ianella P, de Campos TA. fim3-24/ptxP-3 genotype is associated to whooping cough outbreak in Brazilian Midwest: The selection of Bordetella pertussis strains driven by vaccine immunization. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2024; 121:105599. [PMID: 38679113 DOI: 10.1016/j.meegid.2024.105599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2024] [Revised: 04/23/2024] [Accepted: 04/25/2024] [Indexed: 05/01/2024]
Abstract
Whopping cough (or Pertussis) is an acute infectious respiratory disease caused by Bordetella pertussis bacteria. The disease is highly transmissible and can be fatal in children under two years old. Since the introduction of vaccine immunization in 1940, Pertussis incidence decreased worldwide. In Brazil, the immunization was introduced in 1977 using the whole cell (wP) vaccine. Despite the high vaccination coverage, an unexpected increase in the number of observed Pertussis cases was observed in 2012. In this year, 2257 cases were reported exceeding the average incidence rate of <1000 cases per year until 2010. This outbreak reached a peak level in 2014 and ended in 2018 according to the Brazilian National Surveillance System (SINAN). To understand the relationship between the outbreak and the vaccination, bacterial isolates (n = 136) from the Brazilian Midwest region obtained during the outbreak were submitted to genotyping of two vaccine loci: ptxP and fim3. Most of isolates (102) were obtained from nursing children (29 days to 2 years old). Genotyping of 94 isolates revealed that fim3-24/ptxP-3 was the most prevalent genotype (68%) associated with the outbreak peak. Two additional genotypes were also observed: fim3-1/ptxP-3 (15%) and fim3-3/ptxP-3 (17%). Conversely, the fim3-1/ptxP-2 genotype, which is harbored by the strain used in the wP vaccine (Bp137), was not observed. These results showed that B. pertussis circulating strains in the outbreak analyzed were different from the strain used for Pertussis immunization in Brazil. These observations provide insights that could be used to target vaccination programs to prevent future whooping cough outbreaks in Brazil.
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Affiliation(s)
- Victor Gomes de Paula
- Programa de Pós-graduação em Biologia Microbiana, Universidade de Brasília, Distrito Federal, Brazil
| | | | - Rafaella Christina Moreira Rocha da Silva
- Programa de Pós-graduação em Biologia Microbiana, Universidade de Brasília, Distrito Federal, Brazil; Departamento de Biologia Celular, Universidade de Brasília, Distrito Federal, Brazil
| | | | | | - Patrícia Ianella
- Embrapa Recursos Genéticos e Biotecnologia, Distrito Federal, Brazil
| | - Tatiana Amabile de Campos
- Programa de Pós-graduação em Biologia Microbiana, Universidade de Brasília, Distrito Federal, Brazil; Departamento de Biologia Celular, Universidade de Brasília, Distrito Federal, Brazil.
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Mahroum N, Karaoglan BS, Ulucam ES, Shoenfeld Y. Vaccine-induced strain replacement: theory and real-life implications. Future Microbiol 2024:1-10. [PMID: 38913745 DOI: 10.1080/17460913.2024.2345003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Accepted: 04/16/2024] [Indexed: 06/26/2024] Open
Abstract
The value of preventive medicine is superior to treatment with vaccinations occupying high priority. Nevertheless, heavy pressure has started to form in regard to strains not included in vaccines contributing to the changing epidemiology of pathogen subtypes leading to 'vaccine-induced strain replacement'. Among other mechanisms, increasing fitness of nonvaccine strains and metabolic shifts in the subtypes have been described. Classical examples include pneumococcal infections and viral diseases, such as the human papilloma virus. Recently, it has been described in SARS-CoV-2, leading to the emergence of new subtypes, such as Omicron and Delta variants. The phenomenon has also been reported in Mycobacterium tuberculosis, Neisseria meningitidis and rotavirus. This study addresses the concepts, examples and implications of this phenomenon.
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Affiliation(s)
- Naim Mahroum
- International School of Medicine, Istanbul Medipol University, Istanbul, Turkey
| | | | | | - Yehuda Shoenfeld
- Zabludowicz Center for Autoimmune Diseases, Sheba Medical Center, Ramat-Gan, Israel
- Reichman University, Herzliya, Israel
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Liu Y, Jiang B, Guo Y, Gao Y, Qian J, Qie C, Shao Z, Li Y, Wu Q. Analysis of prevailing pertussis strains from different regions in China after the application of acellular vaccines. Chin Med J (Engl) 2023:00029330-990000000-00618. [PMID: 37200036 DOI: 10.1097/cm9.0000000000002244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Indexed: 05/19/2023] Open
Affiliation(s)
- Yamin Liu
- Department of Respiratory, Tianjin Medical University General Hospital, Tianjin 300052, China
- Institute of Hepatology, Tianjin Second People's Hospital, Tianjin 300192, China
- Department of Infectious Disease, Clinical School of the Second People's Hospital, Tianjin Medical University, Tianjin 300192, China
| | - Bei Jiang
- Institute of Hepatology, Tianjin Second People's Hospital, Tianjin 300192, China
- Department of Infectious Disease, Clinical School of the Second People's Hospital, Tianjin Medical University, Tianjin 300192, China
| | - Yu Guo
- Department of Clinical Laboratory, Nankai Hospital, Tianjin 300100, China
| | - Yuan Gao
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
- State Key Laboratory for Infectious Disease Prevention and Control, Beijing 102206, China
| | - Jing Qian
- Institute of Hepatology, Tianjin Second People's Hospital, Tianjin 300192, China
- Department of Infectious Disease, Clinical School of the Second People's Hospital, Tianjin Medical University, Tianjin 300192, China
| | - Chunhua Qie
- Institute of Hepatology, Tianjin Second People's Hospital, Tianjin 300192, China
- Department of Infectious Disease, Clinical School of the Second People's Hospital, Tianjin Medical University, Tianjin 300192, China
| | - Zhujun Shao
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
- State Key Laboratory for Infectious Disease Prevention and Control, Beijing 102206, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang 310005, China
| | - Ying Li
- Institute of Hepatology, Tianjin Second People's Hospital, Tianjin 300192, China
- Department of Infectious Disease, Clinical School of the Second People's Hospital, Tianjin Medical University, Tianjin 300192, China
| | - Qi Wu
- Department of Respiratory, Tianjin Medical University General Hospital, Tianjin 300052, China
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Fu P, Zhou J, Meng J, Liu Z, Nijiati Y, He L, Li C, Chen S, Wang A, Yan G, Lu G, Zhou L, Zhai X, Wang C. Emergence and spread of MT28 ptxP3 allele macrolide-resistant Bordetella pertussis from 2021 to 2022 in China. Int J Infect Dis 2023; 128:205-211. [PMID: 36632892 DOI: 10.1016/j.ijid.2023.01.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 12/05/2022] [Accepted: 01/03/2023] [Indexed: 01/11/2023] Open
Abstract
OBJECTIVES To reveal the clinical and molecular characteristics of Bordetella pertussis (BP) prevalent in Shanghai, China. METHODS A total of 9430 children with suspected pertussis from 2021 to 2022 were included, and nasopharyngeal swab samples were collected for polymerase chain reaction detection, culture, antimicrobial susceptibility testing, and 23S rRNA gene A2047G detection. BP strains were typed using multilocus variable-number tandem-repeat analysis and virulence genotyping. RESULTS Of 9430 cases, 5.1% and 1.6% were confirmed by polymerase chain reaction and culture, respectively. Infants (aged <1 year) accounted for 24.7% and presented much more severe symptoms than noninfants. Pertussis was most frequently detected in infants aged 0-6 months (11.3∼14.0%) and children aged >6-10 years (10.8∼21.7%). Macrolide-resistant BP (MRBP) accounted for 89.3%, and all carried the A2047G mutation. There were six multilocus variable-number tandem-repeat analysis types (MTs), including MT28 (62.0%), MT195 (20%), MT27 (10.0%), MT104 (4.7%), MT55 (2.7%), and MT32 (0.7%). BP strains with pertussis toxin (ptx)P3/(pertactin) prn2/ptxC2/ptxA1/(fimbrial proteins) fim2-1/fim3-1, including MT27, MT28, and MT32, accounted for 72.7%, among which MT27 and MT32 were macrolide-sensitive BP, whereas most (94.6∼100%) of MT28 were MRBP. Strains harboring ptxP1/prn1/ptxC1/ptxA1/fim2-1/fim3-1, including MT55, MT104, and MT195, belonged to macrolide-sensitive BP. CONCLUSION The emergence and spread of MT28 ptxP3-MRBP was first reported in China, highlighting the importance of continuous surveillance of ptxP3-MRBP to prevent its potential circulation.
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Affiliation(s)
- Pan Fu
- Department of Clinical Microbiology Laboratory, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China; Nosocomial Infection Control Department, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Jinlan Zhou
- Pediatric intensive care unit, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Jianhua Meng
- Department of Hematology and Oncology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Zhiwei Liu
- Department of Clinical Laboratory, Taian Maternity and Child Health Hospital, Taian, Shandong Province, China
| | - Yaxier Nijiati
- Orthopedics Department, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Leiyan He
- Department of Clinical Microbiology Laboratory, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Chunling Li
- Department of Clinical Microbiology Laboratory, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Saige Chen
- Department of Clinical Microbiology Laboratory, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Aimin Wang
- Department of Clinical Microbiology Laboratory, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Gangfeng Yan
- Pediatric intensive care unit, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Guoping Lu
- Pediatric intensive care unit, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Lijun Zhou
- Outpatient and Emergency Management Office, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China.
| | - Xiaowen Zhai
- Department of Hematology and Oncology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China.
| | - Chuanqing Wang
- Department of Clinical Microbiology Laboratory, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China; Nosocomial Infection Control Department, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China.
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Yin Z, Zheng C, Fang Q, Wen T, Wang S, Li J, Gong X, Xiang Z. Comparing the pertussis antibody levels of healthy children immunized with four doses of DTap-IPV/Hib (Pentaxim) combination vaccine and DTaP vaccine in Quzhou, China. Front Immunol 2023; 13:1055677. [PMID: 36685526 PMCID: PMC9852981 DOI: 10.3389/fimmu.2022.1055677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 12/16/2022] [Indexed: 01/09/2023] Open
Abstract
Despite the high coverage of pertussis vaccines in high-income countries, pertussis resurgence has been reported in recent years, and has stimulated interest in the effects of vaccines and vaccination strategies. Immunoglobulin G (IgG) antibodies against pertussis toxoid (PT), filamentous hemagglutinin (FHA), and pertactin (PRN) after immunization with four doses of co-purified or component vaccines were determined by enzyme-linked immunosorbent assay (ELISA). Serological data of PT-IgG geometric mean concentrations (GMCs) over time since vaccination were used to fit the mathematical models. A total of 953 children were included in this study; 590 participants received four doses of the component acellular vaccine and 363 participants received four doses of the co-purified acellular vaccine. The GMCs and the seropositivity rate of pertussis IgG were significantly influenced by the production methods, and the immunogenicity of the component acellular vaccine was superior to that of the co-purified acellular vaccine. The fitted mathematical models for the component acellular vaccine and the co-purified acellular vaccine were Y=91.20e-0.039x and Y=37.71x-0.493, respectively. The initial GMCs of the component acellular vaccine was higher than that of the co-purified acellular vaccine, but both were similar at 72 months after immunization. Pertussis IgG levels waned over time after four doses of acellular pertussis vaccine, regardless of whether component or co-purified vaccine was used. The development and promotion of component acellular pertussis vaccines should be accelerated in China, and booster doses of pertussis vaccine in adolescents, adults, and pregnant women should be employed.
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Affiliation(s)
- Zhiying Yin
- Department of Immunity, Quzhou Center for Disease Control and Prevention, Quzhou, Zhejiang, China,School of Public Health, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China,*Correspondence: Zhiying Yin, ; Ziling Xiang,
| | - Canjie Zheng
- Department of Immunity, Quzhou Center for Disease Control and Prevention, Quzhou, Zhejiang, China
| | - Quanjun Fang
- Department of Immunity, Quzhou Center for Disease Control and Prevention, Quzhou, Zhejiang, China
| | - Tingcui Wen
- School of Public Health, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Shuangqing Wang
- Department of Immunity, Quzhou Center for Disease Control and Prevention, Quzhou, Zhejiang, China
| | - Junji Li
- Department of Immunity, Quzhou Center for Disease Control and Prevention, Quzhou, Zhejiang, China
| | - Xiaoying Gong
- Department of Immunity, Quzhou Center for Disease Control and Prevention, Quzhou, Zhejiang, China
| | - Ziling Xiang
- Department of Immunity, Quzhou Center for Disease Control and Prevention, Quzhou, Zhejiang, China,*Correspondence: Zhiying Yin, ; Ziling Xiang,
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Fu P, Zhou J, Yang C, Nijiati Y, Zhou L, Yan G, Lu G, Zhai X, Wang C. Molecular Evolution and Increasing Macrolide Resistance of Bordetella pertussis, Shanghai, China, 2016-2022. Emerg Infect Dis 2023; 30:29-38. [PMID: 38146984 PMCID: PMC10756392 DOI: 10.3201/eid3001.221588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2023] Open
Abstract
Resurgence and spread of macrolide-resistant Bordetella pertussis (MRBP) threaten global public health. We collected 283 B. pertussis isolates during 2016-2022 in Shanghai, China, and conducted 23S rRNA gene A2047G mutation detection, multilocus variable-number tandem-repeat analysis, and virulence genotyping analysis. We performed whole-genome sequencing on representative strains. We detected pertussis primarily in infants (0-1 years of age) before 2020 and older children (>5-10 years of age) after 2020. The major genotypes were ptxP1/prn1/fhaB3/ptxA1/ptxC1/fim2-1/fim3-1 (48.7%) and ptxP3/prn2/fhaB1/ptxA1/ptxC2/fim2-1/fim3-1 (47.7%). MRBP increased remarkably from 2016 (36.4%) to 2022 (97.2%). All MRBPs before 2020 harbored ptxP1, and 51.4% belonged to multilocus variable-number tandem-repeat analysis type (MT) 195, whereas ptxP3-MRBP increased from 0% before 2020 to 66.7% after 2020, and all belonged to MT28. MT28 ptxP3-MRBP emerged only after 2020 and replaced the resident MT195 ptxP1-MRBP, revealing that 2020 was a watershed in the transformation of MRBP.
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Affiliation(s)
| | | | - Chao Yang
- National Children's Medical Center, Shanghai, China (P. Fu, J. Zhou, Y. Nijiati, L. Zhou, G. Yan, G. Lu, X. Zhai, C. Wang)
- Chinese Academy of Sciences, Shanghai (C. Yang)
| | - Yaxier Nijiati
- National Children's Medical Center, Shanghai, China (P. Fu, J. Zhou, Y. Nijiati, L. Zhou, G. Yan, G. Lu, X. Zhai, C. Wang)
- Chinese Academy of Sciences, Shanghai (C. Yang)
| | - Lijun Zhou
- National Children's Medical Center, Shanghai, China (P. Fu, J. Zhou, Y. Nijiati, L. Zhou, G. Yan, G. Lu, X. Zhai, C. Wang)
- Chinese Academy of Sciences, Shanghai (C. Yang)
| | - Gangfen Yan
- National Children's Medical Center, Shanghai, China (P. Fu, J. Zhou, Y. Nijiati, L. Zhou, G. Yan, G. Lu, X. Zhai, C. Wang)
- Chinese Academy of Sciences, Shanghai (C. Yang)
| | - Guoping Lu
- National Children's Medical Center, Shanghai, China (P. Fu, J. Zhou, Y. Nijiati, L. Zhou, G. Yan, G. Lu, X. Zhai, C. Wang)
- Chinese Academy of Sciences, Shanghai (C. Yang)
| | - Xiaowen Zhai
- National Children's Medical Center, Shanghai, China (P. Fu, J. Zhou, Y. Nijiati, L. Zhou, G. Yan, G. Lu, X. Zhai, C. Wang)
- Chinese Academy of Sciences, Shanghai (C. Yang)
| | - Chuanqing Wang
- National Children's Medical Center, Shanghai, China (P. Fu, J. Zhou, Y. Nijiati, L. Zhou, G. Yan, G. Lu, X. Zhai, C. Wang)
- Chinese Academy of Sciences, Shanghai (C. Yang)
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Xu Z, Hu D, Luu LDW, Octavia S, Keil AD, Sintchenko V, Tanaka MM, Mooi FR, Robson J, Lan R. Genomic dissection of the microevolution of Australian epidemic Bordetella pertussis. Emerg Microbes Infect 2022; 11:1460-1473. [PMID: 35543519 PMCID: PMC9176669 DOI: 10.1080/22221751.2022.2077129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Whooping cough (pertussis) is a highly contagious respiratory disease caused by the bacterium Bordetella pertussis. Despite high vaccine coverage, pertussis has re-emerged in many countries including Australia and caused two large epidemics in Australia since 2007. Here, we undertook a genomic and phylogeographic study of 385 Australian B. pertussis isolates collected from 2008 to 2017. The Australian B. pertussis population was found to be composed of mostly ptxP3 strains carrying different fim3 alleles, with ptxP3-fim3A genotype expanding far more than ptxP3-fim3B. Within the former, there were six co-circulating epidemic lineages (EL1 to EL6). The multiple ELs emerged, expanded, and then declined at different time points over the two epidemics. In population genetics terms, both hard and soft selective sweeps through vaccine selection pressures have determined the population dynamics of Australian B. pertussis. Relative risk estimation suggests that once a new B. pertussis lineage emerged, it was more likely to spread locally within the first 1.5 years. However, after 1.5 years, any new lineage was likely to expand to a wider region. Phylogenetic analysis revealed the expansion of ptxP3 strains was also associated with replacement of the type III secretion system allele bscI1 with bscI3. bscI3 is associated with decreased T3SS secretion and may allow B. pertussis to reduce immune recognition. This study advanced our understanding of the epidemic population structure and spatial and temporal dynamics of B. pertussis in a highly immunized population.
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Affiliation(s)
- Zheng Xu
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia
| | - Dalong Hu
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia
| | - Laurence Don Wai Luu
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia
| | - Sophie Octavia
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia
| | - Anthony D Keil
- Department of Microbiology, PathWest Laboratory Medicine WA, Perth Children's Hospital, Perth, Australia
| | - Vitali Sintchenko
- Centre for Infectious Diseases and Microbiology-Public Health, Institute of Clinical Pathology and Medical Research, NSW Health Pathology and Westmead Hospital, Sydney, Australia.,Sydney Institute for Infectious Diseases, The University of Sydney, Sydney, Australia
| | - Mark M Tanaka
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia
| | - Frits R Mooi
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia
| | - Jenny Robson
- Sullivan Nicolaides Pathology, Queensland, Australia
| | - Ruiting Lan
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia
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