Melioidosis is a tropical disease of high mortality caused by the environmental 
bacterium, Burkholderia pseudomallei. We have collected clinical isolates from 
the highly endemic Northern Territory of Australia routinely since 1989, and 
animal and environmental B. pseudomallei isolates since 1991. Here we provide a 
complete record of all B. pseudomallei multilocus sequence types (STs) found in 
the Northern Territory to date, and distribution maps of the eight most common 
environmental STs. We observed surprisingly restricted geographic distributions 
of STs, which is contrary to previous reports suggesting widespread 
environmental dissemination of this bacterium. Our data suggest that B. 
pseudomallei from soil and water does not frequently disperse long distances 
following severe weather events or by migration of infected animals.