Study on the Basic Plague Pattern of Jianchuan Plague Natural Focus, Yunnan Province, China

Since the plague natural focus of Jianchuan was found in 1974, it had broken the disputation whether Yunnan has plague natural focus among Chinese and foreign scholars for long. Because the focus locates the middle part of transversal mountains with higher biological diversity and complex landscape, many problems raised at beginning in distinguishing the major hosts and vectors, modeling the structure of the focus, and resolving the contradiction between theory and excitation. In review of that, according to the principle of unified of biological structure and function, the basic plague pattern has been systematically studied on through the generalized information concept in this paper. It suggests that the focus takes the community of Apodemus chevrieri + Rattus norvegicus: Neopsylla specialis + Frontopsylla. spadix + Menopsyllus anisus + Loptopsylla segnis as maintenance subsystem, the community of E. miletus: Ctenophthalmus quadratus + Neopsylla specialis as epidematic (amplifying) subsystem, the communities of squirrel rodent-flea as alternate subsystem. The relationship between subsystems is nonlinear. No human plague case is determined by the systematicness of the plague ecosystem. The possibility of human plague will remain in systemic changing or coming into chaos. Although most researches try to analysis of plague as system by means of experiments with many quantitative criterion, these measures are difficult to comprehension the systemic essence without application of the concept of systemic theory. They are often direct, discursive and paradoxical description of appearance rather than the analysis and generalization of interaction relationship between elements, thus reversing the basic ecological concept of Y. pestis as a living thing and agent of plague.