Isolation of Yersinia pestis phage from the Lianghe plague foci of Domestic rats and its epidemiological significance
ZHANG Hai-peng1, ZHONG You-hong1, DUAN Cun-juan1, GUO Mu1, DUAN Biao1, LI Wei2, WANG Peng1, WU He-song1
1.Yunnan Provincial Key Laboratory for Zoonosis Control and Prevention, Yunnan Institute for Endemic Disease Control and Prevention, Dali 671000,China; 2.State Key Laboratory For Infectious Disease Prevention and Control, Institute for Communicable Disease Prevention and Control, Chinese Center for Disease Control and Prevention, Beijing 102206, China
Abstract：To investigate whether the host animals of the plague foci in Lianghe County carry the Yersinia pestis phage, and to explore its epidemiological significance. In 2017, samples from four epidemic towns were collected in Lianghe plague foci. Vaccine strain of EV76 were used as feeding bacteria, and used double-layer plate method were used to isolate Yersinia pestis phages. At the same time, some phages were selected for electron microscopy scanning. 29 of Yersinia pestis phages were isolated from 338 samples (234 of Rattus flavipectus, 43 of Suncus murinus and 61 of the remaining), with total isolation rate of 8.58%(29/338). Among them, 19 were isolated from Rattus flavipectus, with a separation rate of 8.12%(19/234), and 8 were isolated from Suncus murinus, with a separation rate of 18.6%(8/43). The Yersinia pestis phages were isolated in all 4 villages, and the highest rate was 16.13% (5/31) in Zhedao Town. The plaque of the phages is divided into three appearance of big (≥2.0 mm), middle (≥1.0 mm,≤2.0 mm) and small (≤1.0 mm). Two phages are identified as the Myoviridae family. The Yersinia pestis phages are common in the plague foci in Lianghe County, and Rattus flavipectus is the main carrier. These Yersinia pestis phages are polymorphic phages of the Myoviridae family, and it is worth further study.
2020, Vol. 36 
