[Edmond Sergent's discoveries on the vectorial transmission of agents of human and animal infectious diseases].

Edmond SERGENT has been head of the Institut Pasteur in Algeria from 1910 to 1963. During these years, he carried out an impressive scientific production and studied a lot of agents responsible for human, animal and plant diseases. In the field of vectorial transmission of infectious diseases, he made two essential discoveries: the transmission of cosmopolitan relapsing fever by human body louse in 1908, a year before Charles NICOLLE discovered the transmission of the classical exanthematic typhus by the same insect, and the transmission of cutaneous leishmaniasis by the phlebotomine sandfly. Moreover he made other discoveries in similar fields, such as the transmission of dromedary trypanosomiasis by Tabanids and later by stomoxys calcitrans, or the transmission of the pigeon Haemoproteus by Lynchia maura. Finally he described the transmission of Theileria dispar (now T. annulata) by the tick Hyalomma mauritanicum (1928).