Henry Foley and the discovery in 1908 of the role played by the louse in the transmission of relapsing fever

The author recalls the very fine clinical, epidemiological and experimental work undertaken since 1907 at Beni Ounif de Figuig, south of Oran near the algerian-moroccan border which led Henry Foley and Edmond Sergent to suspect and later demonstrate the exclusive role played by the louse (Pediculus corporis or more precisely P. vestimenti) in the transmission of relapsing fever of which they studied an important epidemic occurring there between 1907-1910. This discovery led them to incriminate also the louse in the transmission of exanthematic typhus of which the epidemiology is practically similar. On the occasion of a tunisian epidemic of relapsing fever Charles Nicolle resumed Sergent's and Foley's work which he contested without any justification. Trying to attribute to himself all the merit of the discovery of the role of the louse in the transmission of relapsing fever, Charles Nicolle quotes Sergent's and Foley's works contesting them with a certain bad faith. In 1912 he mentions only Sergent's and Foley's 1910 works (posterior of only one year to his confirmation of the role of the louse in the transmission of exanthematic typhus) and ignores totally their 1908 preliminary paper. One must therefore give full credit to Henry Foley associated with Edmond Sergent for this essential discovery of the role of the louse in human pathology in which they occupy the first place.