Ectoparasites of Chevrier's field mouse, Apodemus chevrieri, in a focus of plague in southwest China.

Chevrier's field mouse, Apodemus chevrieri Milne-Edwards (Rodentia: Muridae), has been identified as the main wild reservoir of plague in the sylvatic plague focus of Yunnan Province, southwest China. Here, the ectoparasite communities of A. chevrieri and the potential medical and veterinary importance of these ectoparasites are described. A high proportion (66%) of 321 mice were found to be infested with ectoparasites. A total of 81 species of ectoparasite, including 48 species of chigger mite, 25 species of mesostigmatid (gamasid) mite, six species of flea and two species of sucking louse were collected. Most species of ectoparasite were relatively uncommon, but a few were abundant. Within this ectoparasite complex, 16 species have previously been reported to be vectors of human disease agents. Apodemus chevrieri would appear therefore to be a natural reservoir for plague bacilli and epidemic haemorrhagic fever (Korean haemorrhagic fever) viruses.