ARCHIVED - Supplement - Proceedings of the National Microbiology Laboratory Pertussis Workshop

Table of Contents

• Summary
• Recommendations
• Vaccine Pressure and Immune Selection on Vaccine Preventable Bacterial Disease Agents (Dr. Raymond Tsang)
• Overview of National Surveillance for Pertussis (Dr. Scott A. Halperin)
• Serologic Tests for the Diagnosis of Pertussis (Dr. Scott A. Halperin)
• The Use of PCR in the Diagnosis of Pertussis (Dr. Susan Richardson)
• A Large Cluster of Pertussis Cases in Toronto, Ontario - Laboratory Investigation (Dr. Frances Jamieson)
• Laboratory Characterization of Bordetella pertussis Strains (Dr. Mark Peppler)
• The Canadian Public Health Laboratory Network
  Meeting Local and Global Challenges in Laboratory Public Health (Dr. Greg Horsman)
• References
• Appendix: List of Participants

Summary

A National Consensus Conference on Pertussis was held in 2002, and a number of recommendations were made for laboratory diagnosis and surveillance. The purpose of the National Microbiology Laboratory Workshop on 7 March, 2006, was to gather Canadian experts in pertussis in order to examine the recommendations made in 2002 and discuss issues related to laboratory diagnosis and strain characterization for surveillance. Participants included representatives from academia, federal and provincial laboratories, hospital laboratories and industry. Twenty-one people attended the workshop, representing Nova Scotia, Newfoundland, Quebec, Ontario, Manitoba, Saskatchewan, Alberta, British Columbia and the United States.

The objectives of the workshop were to (1) discuss and establish recommendations for a diagnostic laboratory system for pertussis; (2) discuss and establish recommendations for a laboratory surveillance system for pertussis; and (3) develop an action plan to implement these recommendations. An initial series of presentations provided a background on pertussis in Canada and consisted of an overview of the national surveillance of the disease; serologic and PCR (polymerase chain reaction) diagnosis; laboratory characterization of pertussis; and an investigation into recent pertussis cases in Toronto. Further presentations described the National Microbiology Laboratory (NML) activities with respect to vaccine preventable bacterial diseases, and the local and global challenges in laboratory public health, discussed by the Canadian Public Health Laboratory Network (CPHLN). The format of the workshop consisted of presentations and full group discussions.

Recommendations

The following is a summary of the recommendations identified during the workshop:

1. Recommendation for a diagnostic laboratory system for pertussis

   • 1.1 PCR diagnosis for pertussis should be encouraged and made widely available in Canada. The NML should provide a laboratory proficiency program for PCR diagnosis of pertussis.

   • 1.2 Culturing of the Bordetella pertussis organism should continue to allow the bacteria to be archived for future reference, or at least appropriate specimens (such as nasopharyngeal aspirates) should be stored frozen such that B. pertussis bacteria may be recovered from the specimen as required.

   • 1.3 The national case definition of pertussis should be revised to reflect the fact that laboratory test results should be interpreted in the context of the clinical presentation of the patient.

   • 1.4 A sero-epidemiology study of pertussis in the Canadian adult population should be considered. This study/project would fulfill two objectives: (i) to understand the level of protective immunity against pertussis in the adult population, which may provide evidence for future recommendation of pertussis vaccination in this population; (ii) to define the role of routine serology for the diagnosis of pertussis in adolescents and adults.

2. Recommendation for a laboratory surveillance system for pertussis:

   • 2.1 A working group with representatives from British Columbia, Alberta, Ontario, Nova Scotia, the NML and the Centre for Infectious Disease Prevention and Control (CIDPC) should be established to examine how to implement a national program to study and characterize strains.

   • 2.2 CIDPC should study effective ways to utilize existing resources or programs to implement sentinel sites for collection of not only B. pertussis strains but also epidemiologic data, such as vaccination history.

3. Action plan to implement the above recommendations:

   • 3.1 CPHLN will initiate a survey to find out which Canadian hospital laboratories are providing PCR diagnosis of pertussis, to identify sites where culture for B. pertussis is being done, and/or to identify potential sites where suitable nasopharyngeal aspirate specimens may be stored frozen for future culture work.

   • 3.2 NML will study the feasibility of providing a PCR proficiency program for pertussis.

   • 3.3 NML will set up a working group to discuss implementing a national strain characterization program.

   • 3.4 CIDPC will study ways to enhance the national surveillance of pertussis by incorporating the laboratory strain characterization component.

   • 3.5 CIDPC will take the lead in revising the national case definition of pertussis to reflect the importance of interpreting laboratory results in the context of compatible clinical and epidemiologic information.

   • 3.6 NML will work with interested parties to examine the feasibility of implementing a standardized enzyme-linked immunosorbent assay (ELISA) for measuring serum antibodies to pertussis as well as the feasibility of carrying out a seroepidemiology study in the Canadian adult population.