It is well known that trypanosomes may be absent for long periods from the peripheral blood of an animal or of a person suffering from an infection by trypanosomes, and that although no treatment has been given. It also frequently happens that the parasites may reappear, after a more or less lengthy absence, in the blood of persons or of animals who have apparently been cured by appropriate treatment of an infection by trypanosomes. It is important to collect instances of such disappearances and recurrences of the parasites in order that an opinion may be formed as to the length of time during which a recurrence is possible in cases of apparent recovery from trypanosomiasis or apparent cure.
II. HUMAN TRYPANOSOMIASIS
The following observations prove that symptoms may be absent for long periods from persons who are infected with trypanosomes, and that those infected may die from