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

Abstract

Babesiosis is an emerging tick-transmitted zoonosis prevalent in large parts of the world. This study was designed to determine the rates of Babesia microti infection among small rodents in Yunnan province, where human cases of babesiosis have been reported. Currently, distribution of Babesia in 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 microti DNA was detected by polymerase chain reaction in 4·3% (72/1672) of the rodents analyzed. The most frequently infected rodent species included Apodemus chevrieri and Niviventer fulvescens. Rodents from forests and shrublands had significantly higher Babesia infection rates. Genetic comparisons revealed that Babesia was 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 of B. microti, supporting the need for further serological investigations in humans.

High prevalence of Babesia microti in small mammals in Beijing

“…Additionally, further consideration should be given for any patient exposures to certain ecological habitat types-specifically broad-leaved forest, shrub, and cropland-as this study has shown that such exposure is considered to be an important risk factor (Tables 3 and 4). Ecological habitat type of forest was also found to be an important risk factor for B. microti infection in other studies in Yunnan [26,27] and in Southeast Asia [28]. Thus, these findings show that forests, the natural habitat for ticks, likely represent areas of high risk for transmission of B. microti to humans, and as such, people either working in or traveling to the forest, should utilize adequate protection.…”

“…To our best knowledge, the greater long-tailed hamster (Tscherskia triton), has not been reported for B. microti infection before, while the other seven species involved in this study were reported in previous studies to serve as probable reservoir hosts for B. microti [11,26,[31][32][33][34]. Our findings indicate the potential role of Tscherskia triton, with such a high infection rate of 33.3% (Table 2), for maintaining an enzootic cycle of B. microti, but further detailed studies are needed to confirm whether it is a reservoir host, an occasional host, or even an enhancing host.…”

“…Hence, the identification of U.S.-type in this study revealed the genetic diversity of B. microti in small mammals in Beijing, as well as that in China as a whole. Previously, the most highly recorded genotype of B. microti was the Kobe-type, including those recorded from Yunnan [26,27], Zhejiang, Fujian, and Taiwan [30,31]. Babesia microti of Ostu-type was also detected from Yunnan province [26,27].…”

“…Previously, the most highly recorded genotype of B. microti was the Kobe-type, including those recorded from Yunnan [26,27], Zhejiang, Fujian, and Taiwan [30,31]. Babesia microti of Ostu-type was also detected from Yunnan province [26,27]. U.S.-type B. microti was only reported from rodents from Xinjiang [16].…”

Molecular Detection and Identification of Babesia spp., and Trypanosoma spp. in One-humped Camel (Camelus dromedarius) in Halayeb and Shalateen, Egypt

“…which is efficiently affected humans through ticks infestation [7]. Babesia microti has been identified in rodents and can efficiently affect human [8,9]. Camel babesiosis is an acute to chronic infectious disease that is distributed all over the world [2].…”