1990s Vibrio cholerae Epidemic, Brazil

sensitive strain P3343110. When tested by long PCR, all 20 S. Java isolates produced a 10,041-bp fragment identical to that produced by P3170700. PCR was used to determine whether the pentaresistant phenotype was due to the presence of the Salmonella genomic island 1 (SGI1) as previously described (5). All 20 strains produced amplicons with primers U7-L12 and LJ-R1 for the left junction and primers 104-RJ and 104D for the right junction. These results indicate that the SGI1 in the strains of S. Java was located in the same chromosomal location as previously described for DT 104 ACSSpSuT but lacks the retronphage found to date only in DT104 strains (6). These findings demonstrated that the ACSSpSuT resistance gene cluster in S. Java isolated from patients in the United Kingdom from 2000 to March 2003 appeared to be chromosomally located and was almost indistinguishable from that found in the epidemic clone of DT104 ACSSpSuT. This resistance gene cluster has also been identified in strains of S. Agona from poultry in Belgium (6), in a strain of S. Paratyphi B from tropical fish in Singapore (7), and a variant cluster in a strain of S. Albany from fish food from Thailand (8). It also appears to be present in isolates of S. Paratyphi B of R-type ACSSpSuT from cases of human infection in France in 2003 (F. Xavier-Weill, pers. comm.). The strains of S. Paratyphi B from Singapore and France were not tested additionally to identify the Java variant. The strains of S. Java with chromosomally integrated ACSSpSuT resistance identified in the United Kingdom are not those associated with poultry in Germany (9) or the Netherlands (10), which have also caused infections in humans in the United Kingdom (1). The latter strains have different phage types, resistant spectrums, pulsed-field profiles, and they possess plasmid-mediated drugresistance. However, several S. Java infections in the United Kingdom have been associated with tropical fish tanks (L.R. Ward, unpub. data), although the strain has not been isolated from this medium. A substantive increase in multiresistant S. Java has also been reported in Australia (D. Lightfoot, pers. comm.). The antibiogram of these isolates are indistinguishable from the isolates of R-type ACSSpSuT made in the United Kingdom. These results suggest either a common origin of the ACSSpSuT-resistance gene cluster in epidemic multiresistant DT104 and multiresistant S. Java or the horizontal transfer of the cluster from DT104 to other Salmonella serovars with a worldwide distribution. In either event, the increasing occurrence of the DT104 resistance gene cluster in potentially epidemic serovars other than S. Typhimurium DT104 is concerning.