Immune protection of birds against a stock of Trypanosoma brucei.

Domestic chickens (Gallus domesticus) infected with a stock of Trypanosoma brucei exhibited a chronic infection that was spontaneously terminated by self-cure. They were then found to be immune to challenge with derivatives of the same trypanosome stock. It is suggested that the ability of birds to cure the infection and retain immunity is due to the particularly efficient nature of their immune responses. These results encourage the view that it may be possible to design effective trypanosome vaccines for use in mammals.