Plasmid encoded multidrug resistance in Salmonella typhi in Vietnam

ABSTRACT

129 isolates of S.typhi multi-drug resistant to Cm, Ap, Te, Tr, Su from Northern, Southern and Central regions of Vietnam during 1995-1997 were examined to detect the ability to transfer gene encoding the resistance to antibiotics and to study molecular characters of it’s R-plasmids. Results indicated the presence of self-transferable plasmid in 90% S.typhi strains from Southern, and 100% strains from Northern and Central regions. These strains carried from 1 to 2 plasmids of molecular weighed 110 MD and 80 MD. Gene encoding the resistance to Cm, Ap, Te, Tr, and Su were found to be located on a large plasmid of 100 MD. All S.typhi strains from 3 regions showed to have large plasmids with identical molecular structure, this indicated the same origin of these S.typhi strains.