[Seroepidemiologic survey on plague in an endemic zone: cumulative results: 1987-1990].

Plague is a bacterial disease, induced by Yersinia pestis growth in rodents, with human transmission by fleas. In numerous cases, lymph node reaction is important. This survey (329 patients and contacts) is the most extensive ever realised, associating plasmidic virulence and immunity studies. From the results, we can retain that: All the strains were 47 Plasmid+. The immunity was precocious, specific, of high titer and persistent. In conclusion, in plaque endemic zone, high bacillus circulation induced a high and perhaps (to prove) protective immunity.