Anti-plague vaccination: Past and future perspectives.

The impact of the three historic plague pandemics will remain engraved fore ver in the collective memory. During the first half of the XXth century, th e development of vaccines inducing protection against bubonic plague the fi rst production of antibiotics, insecticides and raticides, could have lead some people to think that eradication was possible. But according to the da ta of epidemiological surveillance, far from disappearing, plague is remain ing or so increasing that it is considered, in some places, as a reemerging disease. Yersinia pestis is highly variable and a multidrug resistant stra in has been isolated in 1995 in the Ambalavo district of Madagascar: This h igh-level of resistance includes the drugs recommended for plague prophylax is and therapy and this observation pointed the fact that Yersinia pestis i s able to acquire the plasmid carrying the resistance genes, under natural conditions. Consequently, it is not unreasonable to think that clinically o minous events could occur again. Moreover currently available vaccines do n ot induce protection against the pneumonic form of plague, and are reactoge nic. Lastly according to some accurate sources, one cannot turn down the as sumption of a genetically engineered strain of Yersinia pestis used as a bi ological weapon by a terrorist organization. So, the surveillance of plague remains a topical activity, as the development of none reactogenic live an d/or inactivated new vaccines, inducing protection against the pneumonic fo rm of the disease.