Epidemiology and Infection

Research Article

Genetic characterization of Mycobacterium avium isolates recovered from humans and animals in Australia

M. M. Feizabadia1, I. D. Robertsona1, D. V. Cousinsa2, D. Dawsona3, W. Chewa4, G. L. Gilberta4 and D. J. Hampsona1 c1

a1 School of Veterinary Studies, Murdoch University, Murdoch, Western Australia 6150

a2 Australian Reference Laboratory for Bovine Tuberculosis, Department of Agriculture, South Perth, Western Australia 6151

a3 State Health Laboratory, Brisbane, Queensland 4000

a4 Mycobacterium Reference Laboratory, Westmead Hospital, Sydney, New South Wales 2145


Genetic relationships amongst 115 mainly Australian isolates of Mycobacterium avium were assessed using multilocus enzyme electrophoresis (MEE). The isolates were divided into 58 electrophoretic types (ETs), with a mean genetic diversity of 0·29. Isolates from humans were closely related to but distinct from those cultured from birds, whilst some porcine isolates belonged to the same ETs as certain human isolates. Pulsed field gel electrophoresis (PFGE) was used to differentiate related isolates, and those from birds and some from other animals, including pigs, were distinguished from the human isolates. The results of MEE and PFGE suggested that certain strains of M. avium may be transmitted between birds and pigs, but there was no clear evidence of transmission to humans. The serovar of the M. avium isolates was not obviously related to their ET assignment or their PFGE type.

(Accepted September 08 1995)


c1 Corresponding author.