GM TestPertussis (Bordetella pertussis)

Submission only upon approval by CDPE

The bacteriological identification of Bordetella pertussis is available only in cases where clinical symptomatology of pertussis exists. Specimen kits containing charcoal transport medium are shipped only upon individual specific request. Direct smears for pertussis are no longer performed because the direct immunofluorescence smear has proven to be unreliable due to non-availability of a specific conjugate.

Collection and Shipping Instructions

1. All specimens must be collected from the nasopharynx by gently inserting the provided calcium alginate nasopharyngeal swab (Calgiswab) into the previously cleared nasal passage. Care must be taken to avoid touching the sides of the nasal passage. When the swab meets resistance, it is gently rotated. Throat swabs are unsatisfactory and will not be accepted.

2. Ensure the charcoal transport medium (CTM) is not out of date. The swab should then be aseptically placed into the CTM. Cut the wire with scissors or wire cutters so that the cap can be secured. Do not bend the wire into the CTM tube, because this procedure might introduce skin flora into the CTM. Label the CTM tube with the date, the patient's name, and date of collection.

3. The CTM may be handled in two different ways. It may be kept at refrigeration temperature from the time inoculated to the time of receipt at the OSPHL. This would mean extra packaging (cold pack) but would allow for immediate shipping. The other method requires incubation of the CTM at 35^oC at least 24-48 hours before shipment to the OSPHL for processing. The CTM can be incubated because it is both a transport and growth medium. Please indicate on the form the number of hours the CTM was incubated prior to transport, or if it was refrigerated.

4. The specimens must be accompanied by one request form completed as thoroughly as possible (type or print legibly).

5. Package the transport tube in such a way as to avoid leakage or breakage in transit.

6. Please arrange the most rapid transport to the OSPHL.

7. If you have any questions concerning these procedures, please call the General Microbiology Section at the OSPHL, 503-693-4100.

Precautions

1. Specimens should be obtained prior to antibiotic therapy.

2. Submission of a swab in transport medium is essential for diagnosis. Submission of a slide only is unsatisfactory.

Reports

Specimen processing and identification is performed Monday through Friday. The B. pertussis organism usually grows within three to four days after inoculation of media. Seven days of incubation (once streaked to an agar plate at OSPHL) are required before reporting specimens as negative. Positive reports are phoned; negative reports will be phoned upon request.

References

1. American Society for Microbiology, Manual of Clinical Microbiology, Fourth Edition, 1995.

2. Oregon State Health Services, Oregon Communicable Disease Summary, Volume 30, No. 40, 1981.