ABSTRACT
Objective To analyze the factors related to the household abundance of rodents in rodent-borne disease foci in the western part of Yunnan province.Methods From July 2011 to October 2012,800 households (20 households in 1 village) were randomly selected in 40 natural villages of 10 counties in western Yunnan where rodent borne disease was endemic to conduct a study on relationship between rodent abundance and environmental factors.Five cages were placed in each household for 3 consecutive nights to capture rodents.The rodent species were identified based on their morphological characteristics.The data on potential factors related to rodent abundance were collected through questionnaires and field observation.A dataset was established by using EpiData software and the analysis was performed with hurdle regression model under R software.Results A total of 421 rodents were captured in 800 households,belonging to 9 species,6 genera,2 families,2 orders.Rattus tanezumi was the predominant species (66.03％).The final hurdle regression model showed that the probability of capturing rodents in the households where family member had high education level and the garbage was placed outside declined by 50％-68％ ; The probability of capturing rodents in the households of Dai and Yi ethnic groups increased by 2.16-2.87 times; The probability of capturing rodents in the households where rodents were observed or vegetables grown near houses increased by 1.54-1.59 times; In the households where many rodents were believed to exist,the probability of capturing rodents and the number of rodents captured increased by 1.59 and 1.84 times respectively.The number of rodents captured in the houses with cement or tile floor increased by 3.62 times.Conclusion The household abundance of rodents in the area in western Yunnan,where the rodent-borne disease survey was conducted,seemed to be closely related to the social economy status,human intervention and ecological environment.To control the abundance of rodents effectively,it is necessary to take these factors into consideration.
ABSTRACT
<p><b>OBJECTIVE</b>To create the fingerprint library of Yunnan Yersinia pestis by pulse field gel electrophoresis(PFGE)with Fse I enzyme digestion method and to study its epidemiological significance.</p><p><b>METHODS</b>We used rare cutting restriction enzyme Fse? to digest Yunnan Yersinia pestis strains that were isolated from foci including Rattus flavipectus Plague Focus,Apodemus chevrieri-Eothenomys miletus Plague Focus and Yulong Plague Focus. Fingerprints to Bionumerics software were used for cluster analysis.</p><p><b>RESULTS</b>30 tested strains were divided into 16 genotypes with the similarity value as 79.8%-100.0% . 16 genotypes wee formed into 4 clusters, with one consisted of only EV76 while the other three belonged to Rattus flavipectus,Apodemus chevrieri- Eothenomys miletus and Yulong clusters, respectively.</p><p><b>CONCLUSIONS</b>PFGE genotypes of Yunnan Yersinia pestis accorded with its ecotypes and biovars, with clustered regional features. The strains isolated from Yulong showed an unique PFGE type, indicating a new clone group was identified.</p>