Abstract: Various pathogens that live or are parasitic in the wild may have the potential to infect humans through evolution, genetic variation, or ecological suitability alteration. Therefore, it is important to carry out risk analysis of spatial and temporal intersection of human and important host animals for traceability tracking of unknown epidemic infections, field environmental health management and early warning. Bats carry a variety of dangerous pathogens. In this paper, a random forest model was constructed to predict the suitable distribution area of bats as the target hosts, and spatial variables related to bats and human activities were integrated to establish a risk assessment model with spatial intersection of humans and bats, and to produce a risk distribution map; for the convenience of administrative management, a risk analysis at the township level as the management unit was conducted. The results show that, 1) The dominant variables affecting bat fitness are average annual precipitation, annual temperature fluctuation range, monthly mean diurnal temperature difference, seasonal variation of temperature, seasonal variation of rainfall and mean temperature of the coldest quarter. 2) The random forest predicted the high fitness distribution area of bats was 9.796 5×10⁴ km², accounting for 24.86% of the total area of Yunnan Province, mainly distributed in southern part of Yunnan Province. 3) The risk assessment of epidemic infection found 45 townships belonging to the high risk area of epidemic infection, with an area of about 0.534 6×10⁴ km² and an affected population of about 2.87 million, mainly distributed in the southern, southwestern and central-eastern parts of Yunnan Province.

Key words: bats, suitable areas, random forest model, risk assessment modeling, spacial distribution