High level resistance to multiple antibiotics has been reported in a strain of Yersinia pestis isolated from a patient with bubonic plague from Madagascar.

Although the patient recovered, the case is of clinical and public health importance as the strain of Y pestis when examined in the laboratory was found to be resistant to all first line antibiotics as well as to the principal alternative drugs for treatment and prophylaxis of plague (New England Journal of Medicine 1997;337:677-80). Although there are naturally occurring strains of tetracycline resistant Y pestis, drug resistance has not been a recognised problem in treating plague or other vector born bacterial diseases until now.

Dr Elizabeth Carniel, from the World Health Organisation Collaborating Centre for Yersinia at the Pasteur Institute in Paris, and her coauthors write: “The fact that the multidrug resistant plasmid was highly transferable in vitro to other strains of Y pestis, …