Table 2. PCR analysis of key genes of toxigenic V. cholerae O1 strains isolated from environmental samples in Haiti.

	Key genes amplified by PCR a										MAMA-PCR b
Strains c	ompW	toxR	tcpA CL	tcpA ET	ctxA	ctxB	rstR ET	rstR CL	rstC ET	rstC CL	ctxB CL	ctxB ET
env894	+	+	-	+	+	+	+	-	+	-	+	-
env898	+	+	-	+	+	+	+	-	+	-	+	-
env901	+	+	-	+	+	+	+	-	+	-	+	-
env949	+	+	-	+	+	+	+	-	+	-	+	-
env955	+	+	-	+	+	+	+	-	+	-	+	-
env961	+	+	-	+	+	+	+	-	+	-	+	-
env1054	+	+	-	+	+	+	+	-	+	-	+	-
env1112	+	+	-	+	+	+	+	-	-	-	+	-
env1177	+	+	-	+	+	+	+	-	-	-	+	-
env1180	+	+	-	+	+	+	+	-	-	-	+	-
env1183	+	+	-	+	+	+	+	-	+	-	+	-
env1218	+	+	-	+	+	+	+	-	+	-	+	-
env1222	+	+	-	+	+	+	+	-	+	-	+	-
env1231	+	+	-	+	+	+	+	-	+	-	+	-
env1239	+	+	-	+	+	+	+	-	-	-	+	-
env1320	+	+	-	+	+	+	+	-	-	-	+	-
env1321	+	+	-	+	+	+	+	-	+	-	+	-

^aGenetic characterization was performed by PCR using convergent primer sets specific for both El Tor and classical V. cholerae O1 strains.

^bAll isolates are V. cholerae O1 biotype El-Tor strains carrying classical ctxB gene as determined by MAMA-PCR.

^cTwelve (70.6%) of the 17 isolates exhibited the presence of rstC ^ET genotype