Investigation of composition and distribution of wild rodents and their ecto-parasites populations in southwestern Zhejiang

Objective To understand the species and geographical distribution of wild rodents and their ecto-parasites populations in the southwest of Zhejiang Province, the data base was established for the formulation prevention and control strategies of plague and other infectious disease in line with local characteristics. Methods From 2018 to 2019, according to the national plague surveillance program, the investigation, sampling, classification and identification of rodents and their ecto-parasite populations, and the serologic and etiologic detection of plague were carried out in six plague surveillance areas in southwestern Zhejiang. Results A total of 989 wild rodents of 10 species, 4 genera and 2 families were captured, with a capture rate of 5.15%, the Apodemus agrarius was the predominant species, and 398 wild rodents carried the ecto-parasites, the total infection rate was 40.24%, and the total parasitic index was 6.05. Moreover, a total of 2409 ecto- parasites belonging to 30 species, 18 genera and 8 families were found, among them, there were 211 fleas belonging to 6 species, 5 genera, 3 families, the flea infection rate was 6.47% and the flea index was 3.30, the predominant species was Neopsylla specialis minpiensis; there were 446 ticks belonging to 5 species, 4 genera and 1 family, the tick infection rate was 16.28% and the tick index was 2.77, the predominant species was Rhipicephalus sanguineus; there were 951 gamasid mites belonging to 9 species, 5 genera and 1 family, the gamasid mites infection rate was 22.24%, and the gamasid mites index was 4.32, the predominant species was Echinolaelaps echidninus; there were 341 chigger mites belonging to 1 family, 2 genera and 3 species, the infection rate of chigger mites was 7.28% and the chigger mites index was 4.74, and the predominant species was Leptotrombidium delicense and there were 460 sucking lice belonging to 7 species, 2 families, 2 genera, the sucking lice infection rate was 9.30%, the sucking lice index was 5.00, and the predominant species was Niviventer hoplopleura. Conclusion Wild rodents are distributed widely in southwestern Zhejiang and their ecto-parasites are various, due to the high parasite infection rate and parasite index in the host, it is recommended to continue the relevant surveillance comprehensively. Except for fleas, it is suggested that the ecological investigation and pathogen detection of ticks, gamasid mites and sucking lice and other ecto-parasites should be strengthened systematically.