[Epidemic recrudescence of the Great Plague in Marseille (May-July 1722): excavation of a mass grave].

The return of some infectious disease has stimulated specialists to study historical aspects of human infections. A major model for this study is Yersinia pestis which has had a great impact on human demography due to the fact that it is highly contagious and has a high mortality rate similar to that of the most lethal viral pathogenic agents. We carried out excavation of a mass grave containing the bodies of victims of an outbreak of bubonic plague that occurred in Marseille from 1720 to 1722. More than 200 skeletons were uncovered from the grave known as the Observance (second district in Marseille). In conjunction with laboratory testing, archival records were studied to determine the conditions and dates surrounding the use of this mass grave and to explain certain findings made at the site. This multidisciplinary approach revealed previously unknown facts concerning the Great Plague and provided new insight into recrudescence of the epidemic in 1722.