A genus of fleas. The common rat flea of temperate regions, N. fasciatus, will, in the absence of rats, bite man and may therefore transmit plague or murine typhus from an infected rat population. The rat flea is also an intermediate host for the larval stage of two tapeworms, Hymenolepis diminuta and H. nana.
A genus of fleas belonging to the order Siphonaptera.