Xenopsylla

The rat flea; a genus of fleas parasitic on the rat and involved in the transmission of bubonic plague. The species X. cheopis serves as a potent vector of Yersinia pestis, largely because its gut becomes “blocked” by a mass of Y. pestis cells that prevents the flea from feeding normally, so that it is inclined to attack humans and other hosts; it is an important source of infection in traditional epidemic areas such as India. X. astia and X. braziliensis are also efficient vectors of plague. [xeno- + G. psylla, flea]

* * *

Xen·op·syl·la .zen-äp-'sil-ə n a genus of fleas of the family Pulicidae including several (as the oriental rat flea) that are important as vectors of plague

* * *

n.

a genus of tropical and subtropical fleas, with some 40 species. The rat flea, X. cheopis, occasionally attacks humans and can transmit plague from an infected rat population; it also transmits murine typhus and two tapeworms, Hymenolepis and H. diminuta.

* * *

Xen·op·syl·la (zen″op-silґə) [xeno- + Gr. psylla flea] a genus of fleas that infest primarily rats; many species transmit disease-producing microorganisms.