Predictors for abundance of Rattus tanezumi in households of commensal rodent plague foci

Abstract

To explore the predictors on the abundance of Rattus (R.) tanezumi in households of commensal rodent plague foci. Thirty natural villages that experienced previous plague cases in Lianghe county, Yunnan province, were selected followed by random selection of 20 households in each village through computer technique. Live traps were set in households to capture small mammals which were then identified to species in the field according to their morphological features. Data on potential factors for abundance of R. tanezumi were collected through questionnaires and field observation and were coded and computerized using EpiData software and further analyzed by hurdle regression model under R software. A total of 166 rodents (133 R. tanezumi and 33 Suncus murinus) were captured. from final multilevel hurdle regression model showed that the likelihood of R. tanezumi captures increased by 1.67- to 2.76-fold in households belonged to Dai ethnic families that stored foodstuff in metal pail, often raising dogs, and having adjacent houses. The number of R. tanezumi captures increased by 2.18-fold in the villages where over 80% of the households would raise chickens. In the villages with communal latrine, the likelihood and the number of R. tanezumi capture increased 1.93-fold and 2.38-fold, respectively. While the likelihood of R. tanezumi captures would reduce by 45% - 61% in those households where there were cats and cattle being raised and maize grown in the village. The number of R. tanezumi captures would reduce by 63% in the households where there were outside toilet. The abundance of R. tanezumi seemed to be closely related to the ecological environment factors. Programs on plague control and prevention should relate to ecological factors that influencing the abundance of R. tanezumi.