parasitological examinations of the cerebrospinal fluid of 20 vervet monkeys ( cercopithecus aethiops ) , that had been infected with trypanosoma rhodesiense , revealed that the csf was regularly infested with trypanosomes in the early phase of the disease , at the earliest on the 13th day , in most of the animals in the 3rd or 4th week , after infection .
C0012634
disease
C0009450
infection