|Townsend, Kirsty - UNIV. OF QUEENSLAND, AU|
|Gunawardana, Gnana - VET RES. INST., SRI LANKA|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: May 1, 2002
Publication Date: April 20, 2002
Citation: TOWNSEND, K.M., GUNAWARDANA, G.A., BRIGGS, R.E. PCR IDENTIFICATION AND TYPING OF PASTEURELLA MULTOCIDA: AN UPDATE. INTERNATIONAL PASTEURELLACEAE SOCIETY CONFERENCE. 2002. Abstract p. 26, #13. Technical Abstract: Conventional serological capsular typing of Pasteurella multocida requires a high degree of maintenance and experience in producing hyperimmune sera stocks. As a result, very few laboratories are capable of typing P. multocida strains. The development of the multiplex capsular PCR typing system (CAP-PCR) for P. multocida has allowed any laboratory with PCR technology to type strains. In addition, the HSB-PCR was thought to be able to provide presumptive identification of haemorrhagic septicaemia-causing serogroup B isolates of P. multocida. The aim of this study was a) to optimise and validate the CAP-PCR at three separate laboratories and b) to further examine the use of the HSB-PCR as a tool for the identification of HS-causing serogroup B P. multocida. While it was not possible to type the same strains at all three laboratories, all strains used to validate the CAP-PCR were capsular typed by conventional methods at the NADC and VRI reference typing laboratories. Briefly, while the PCR results of the majority of strains supported the previous capsular typing, a number of discrepancies were observed, in which most were a result of not obtaining any capsular product by PCR. The remaining conflicts were a clear difference in capsular type between the conventional method and PCR, with some strains typed as both capsular group A and F by the CAP-PCR. With regards to the HSB-PCR, 32 strains of P. multocida isolated from pigs in Vietnam were analysed by the CAP-PCR and HSB-PCR. Of these strains, 19 were identified as positive by the HSB-PCR. These were typed as serogroup B (8) and serogroup D (11) by the CAP-PCR. DNA sequencing analysis indicated that the fragments amplified from both serogroups were identical. These results suggest that extreme caution should be maintained when using the HSB-PCR without confirmation of capsular serogroup as a method of identifying HS-causing serogroup B P. multocida.