The World Health Organization/Food and Agriculture Organization Collaborating Center for Reference and Research on Leptospirosis, Western Pacific Region, is part of Queensland Health Scientific Services, Queensland Health. In 1999 there was a marked increase in human leptospirosis notifications in North Queensland. Australia, over the period of January to May. There were 216 notifications for the state of Queensland in 1999, compared with 108 in 1998 and 64 in 1997. By April 1999, the Reference Laboratory and Queensland Health's Tropical Public Health Unit (TPHU), Cairns, had reported an outbreak of leptospirosis in North Queensland. Notifications reported for the North Queensland Health districts of Cairns, Tablelands and Innisfail were the highest, with the majority involving workers in the banana industry. The outbreak resulted from infections with a number of serovars, mostly attributed to serovars Australis and Zanoni. Sixty leptospiral isolates were obtained from human cases in North Queensland during the outbreak. The hospitalization rate was in excess of 50%. The Queensland Health's TPHU has implemented a program to educate target industries and the community on the risks and prevention strategies associated with leptospirosis.