Detection of Kobe-type and Otsu-typeBabesia microtiin wild rodents in China's Yunnan province

Abstract

SUMMARYBabesiosis is an emerging tick-transmitted zoonosis prevalent in large parts of the world. This study was designed to determine the rates ofBabesia microtiinfection among small rodents in Yunnan province, where human cases of babesiosis have been reported. Currently, distribution ofBabesiain its endemic regions is largely unknown. In this study, we cataloged 1672 small wild rodents, comprising 4 orders, from nine areas in western Yunnan province between 2009 and 2011.Babesia microtiDNA was detected by polymerase chain reaction in 4·3% (72/1672) of the rodents analyzed. The most frequently infected rodent species includedApodemus chevrieriandNiviventer fulvescens. Rodents from forests and shrublands had significantly higherBabesiainfection rates. Genetic comparisons revealed thatBabesiawas most similar to the Kobe- and Otsu-type strains identified in Japan. A variety of rodent species might be involved in the enzootic maintenance and transmission ofB. microti, supporting the need for further serological investigations in humans.