[Plasmids of incompatibility group H among multiresistant "Salmonella" (author's transl)].

A total of 449 multiresistant strains of Salmonella recently isolated from human beings and animals in France and in Belgium and belonging to 21 serotypes, were screened for the presence of IncH R plasmids. These plasmids were identified in 236 strains belonging to 14 different serotypes: mainly S. typhimurium, S. schwarzengrund and S. saint-paul, but not in S. dublin nor S. kedougou. The IncH R plasmids confer resistance to four or more drugs and to tellurium compounds. The properties of 14 plasmids were studied by genetic methods and agarose gel electrophoresis following digestion with EcoRI: they showed a great degree of relatedness.