They are infected with trypanosomes, a kind of attenuated worm that circulates in the blood, but fortunately not the variety that causes sleeping sickness.

So the donkey and the Somali mule that generations of fly have rendered tolerant to the trypanosome are the most reliable of our beasts of burden.

The wild game, more especially the water buck and the buffalo whose blood is teeming with these trypanosomes, but who, from generations of infection, have acquired an immunity from these parasites, keep these flies infected.

From worms he went to Protozoa-Trypanosomes, sleeping sickness, host tsetse-flyshowed life history comparatively, propagated in secondary host or encysting in primary hostsimilarly malarial germs spread by Anopheles mosquitoesall very interesting.

Atkinson has found a trypanosome in the fishit has been stained, photographed and drawnan interesting discovery having regard to the few species that have been found.

A trypanosome is the cause of 'sleeping sickness.'

Its connection with the trypanosome-bearing insects was as yet unsuspected, and, to me, its symptoms were absolutely unknown.