Kimberley Simmonds1, Sumana Fathima2, Linda Chui3, Marguerite Lovgren2, Penny Shook2, Michelle Shuel4, Gregory J Tyrrell3, Raymond Tsang4, Steven J Drews5. 1. Alberta Health, Surveillance and Assessment Branch, Edmonton, Alberta, Canada; University of Calgary, Calgary, Alberta, Canada. 2. Provincial Laboratory for Public Health (ProvLab), Walter MacKenzie Health Science Centre, University of Alberta Hospital, 8440 112 Street, Edmonton, Alberta T6G 2J2, Canada. 3. Provincial Laboratory for Public Health (ProvLab), Walter MacKenzie Health Science Centre, University of Alberta Hospital, 8440 112 Street, Edmonton, Alberta T6G 2J2, Canada; University of Alberta, Edmonton, Alberta, Canada. 4. National Microbiology Laboratory, Health Canada, Winnipeg, Manitoba, Canada. 5. Provincial Laboratory for Public Health (ProvLab), Walter MacKenzie Health Science Centre, University of Alberta Hospital, 8440 112 Street, Edmonton, Alberta T6G 2J2, Canada. Electronic address: steven.drews@albertahealthservices.ca.
Abstract
OBJECTIVES: The purpose of this study was to undertake an epidemiological analysis of an increase in Bordetella pertussis activity during the period January 1 to August 31, 2012 in Alberta, Canada. B. pertussis testing was done using an IS481 real-time PCR assay with PCR-positive and indeterminate specimens cultured and stored for further analysis. METHODS: Laboratory data were linked to Alberta Health (AH) cases that were reported in the Communicable Disease Reporting System (CDRS) to identify case isolates; exclusion criteria were used to avoid biases. Case isolates were analyzed at the National Microbiology Laboratory (NML) by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Pertussis immunization data were extracted from the Alberta Provincial Immunization Repository (Imm/ARI) and linked to the pertussis cases. RESULTS: Using PFGE and MLST, 52 case isolates could be divided into two main sequence type groups: 41 cases belonged to the ST-1 group (ST-1 and the novel ST-19) and 11 cases belonged to the ST-2 group (ST-2 and the novel ST-20). Of the total cases genotyped (N=52), 18 (34.6%) had a history of immunization, 28 (53.8%) were not immunized, and six (11.6%) had an unknown immunization history. Of the total non-immunized cases, 25/28 (89.2%) belonged to the ST-1 group. Furthermore, of the 41 ST-1 group cases, 25 were not immunized compared to only three of the ST-2 group cases (p=0.0004, Fisher's exact test). CONCLUSIONS: This study shows the dominance of two genotypes of B. pertussis in our jurisdiction and indicates less pertussis immunization in individuals infected with the ST-1 group.
OBJECTIVES: The purpose of this study was to undertake an epidemiological analysis of an increase in Bordetella pertussis activity during the period January 1 to August 31, 2012 in Alberta, Canada. B. pertussis testing was done using an IS481 real-time PCR assay with PCR-positive and indeterminate specimens cultured and stored for further analysis. METHODS: Laboratory data were linked to Alberta Health (AH) cases that were reported in the Communicable Disease Reporting System (CDRS) to identify case isolates; exclusion criteria were used to avoid biases. Case isolates were analyzed at the National Microbiology Laboratory (NML) by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Pertussis immunization data were extracted from the Alberta Provincial Immunization Repository (Imm/ARI) and linked to the pertussis cases. RESULTS: Using PFGE and MLST, 52 case isolates could be divided into two main sequence type groups: 41 cases belonged to the ST-1 group (ST-1 and the novel ST-19) and 11 cases belonged to the ST-2 group (ST-2 and the novel ST-20). Of the total cases genotyped (N=52), 18 (34.6%) had a history of immunization, 28 (53.8%) were not immunized, and six (11.6%) had an unknown immunization history. Of the total non-immunized cases, 25/28 (89.2%) belonged to the ST-1 group. Furthermore, of the 41 ST-1 group cases, 25 were not immunized compared to only three of the ST-2 group cases (p=0.0004, Fisher's exact test). CONCLUSIONS: This study shows the dominance of two genotypes of B. pertussis in our jurisdiction and indicates less pertussis immunization in individuals infected with the ST-1 group.
Authors: Alex Marchand-Austin; Raymond S W Tsang; Jennifer L Guthrie; Jennifer H Ma; Gillian H Lim; Natasha S Crowcroft; Shelley L Deeks; David J Farrell; Frances B Jamieson Journal: J Clin Microbiol Date: 2017-02-22 Impact factor: 5.948
Authors: Natasha S Crowcroft; Kevin L Schwartz; Rachel D Savage; Cynthia Chen; Caitlin Johnson; Ye Li; Alex Marchand-Austin; Shelly Bolotin; Shelley L Deeks; Frances B Jamieson; Steven J Drews; Margaret L Russell; Lawrence W Svenson; Kimberley Simmonds; Christiaan H Righolt; Christopher Bell; Salaheddin M Mahmud; Jeffrey C Kwong Journal: Clin Infect Dis Date: 2021-07-01 Impact factor: 9.079
Authors: E L Rocha; D Leite; C H Camargo; L M Martins; R S N Silva; V P Martins; T A Campos Journal: Epidemiol Infect Date: 2017-02-21 Impact factor: 4.434