A survey of small mammals and their parasitic fleas in households of western Yunnan Province

Abstract

Objective To investigate and analyze proportion and distribution of small mammals and their parasitic fleas in households of western Yunnan Province and evaluate the risk of plague occurrence.Methods During the period from 2011 to 2012,800 households （20 households in each village） of 40 natural villages from 10 counties of western Yunnan Province were randomly selected and five live-traps per household were placed for three continuous nights to capture small mammals.Fleas from trapped small mammals were collected in laboratory.Small mammal density,flea infection,and flea index were calculated.Flea infections for small mammal species were compared using Chi square test.Results A total of 421 small mammals were captured,which belonged to 2 orders 2 families 6 genera and 9 species.General small mammal density was 3.51%（421/12 000）.The number of Rattus tanezumi was 278,which accounted for 66.03%.The highest density of Rattus tanezumi was 7.83% （94/ 1 200） in Mangshi.But Rattus tanezumi was not captured in Deqin County.A total of 992 fleas,which belonged to 3 families 5 genera and 5 species,were collected from 170 small mammals.General flea infection was 40.38% （170/421）.General flea index was 2.36 （992/421）.Among 992 fleas,Leptopsylla segnis and Xenopsylla cheopis accounted for 47.78% （474/992） and 43.25% （429/992）,respectively.Xenopsylla cheopis flea index for Rattus tanezumi was 1.27 （353/278）.Flea infection of Rattus tanezumi （53.6%,149/278） was highest,and Xenopsylla c heopis infection of Rattus tanezumi（35.6%,99/278） was highest.Conclusions In households of western Yunnan Province,Rattus tanezumi is predominant species,Leptopsylla segnis and Xenopsylla cheopis are dominant parasitic fleas and they are also dominant parasitic flea of Rattus tanezumi.The risk of plague occurrence still exists in Mangshi,Yunxian and Gengma counties with previous plague experience. Key words: Small mammal; Parasitic flea; Household; Western Yunnan Province