Attention should be directed to the probable rôle of the rat as a disseminating agent of the relapsing fever of Panama and presumably of Central America, Mexico, Colombia and Venezuela.
In a set of very convincing experiments, Bates, Dunn and St. John1 have recently demonstrated by human experimentation that the tick Ornithodorus talaje Guérin, 1849 is the natural transmitting agent of the relapsing fever of Panama.
Epidemiologic testimony and the argument from analogy with O. moubata and Spirochaeta duttoni had been presented2 some time before the actual demonstration of the tick O. talaje as the definitive host and carrier of the spirochete had been made.
My own observations on O. talaje date back to 1905, when nymphs of this species were first taken from rats (Mus rattus) caught in buildings on Ancon Hospital grounds. Adults of the species were collected in August, 1910, in the Panaman village of