TRYPANOSOMIASIS EXPEDITION TO THE CONGO 83 
this time the appetite was poor, and the animal seemed to be failing. From April 15 
to 22 parasites were present in fair numbers again, but are now once more scanty. 
No rise of temperature was associated with this temporary increase. Slight 
diminution of haemoglobin and red cells has been observed. The animal is now in 
better condition than it was a month ago. 
Strain derived from the Blood of Trypanosome Fever Cases in Uganda 
Rats. — Incubation from twentv-four to thirty-one days. Duration from one to 
four months. This strain was an attentuated one and has died out. Parasites were 
rarely present, and onlv in verv small numbers. 
Comparison of Symptoms in Animals inoculated with the above 
different Strains 
It will be seen that our results have been practically the same whatever the 
strain used. In rats and mice the same chronic disease, periodicity in appearance of 
parasites, and absence of symptoms are in all cases observed as were described by 
Dutton and Todd. M. Brumpt and M. Wurtz have described' very marked 
symptoms in mice and rats inoculated from Congo sleeping sickness cases — e.g., 
progressive emaciation, intermittent paralvsis or the posterior quarters, oedema 01 
the perineum, and sometimes acute nervous affections. We have observed none of 
these symptoms ; occasionally we have noted slight oedema post-mortem, but never in 
sufficient degree to be detected before death. In guinea-pigs there is with all strains 
the same lengthy incubation period. In those infected up to the present (with 
Gunjur and Congo blood strains) there is the same more or less chronic disease, 
characterized by loss of weight and constant presence of parasites in the blood. In 
rabbits we have produced with all strains the same chronic disease with fairly constant 
presence of parasites, loss of weight and anaemia. In cats the disease is the same 
with all strains, with rise of temperature on appearance of parasites, fairly constant 
presence of parasites, and absence of other symptoms so far as we have yet observed. 
In dogs and puppies there are no differences to be noted. Incubation periods are the 
same, and whatever strain be used there is the same constant presence of parasites in 
the blood, with loss of weight and anaemia. In goats and donkeys no differences 
have been observed between the strains used. In monkeys infection is readily 
produced with all strains, even with very small doses, and parasites are fairly constantly 
present in the blood, often in considerable numbers. Similar symptoms are observed 
with the different strains — viz., slight loss of weight, anaemia, rise of temperature, 
especially with the first appearance of parasites in the blood, and occasionally localized 
oedema. We have observed no marked tendency to sleep in our monkeys ; when a 
1. Brumpt et Wurtz : Mala.de duSommeil Experimentale, etc., Comptes Rendus de la Socie'te de i?/o/og«, tome lvi, 1904, No. 12, 
Avril ler pp. 567-73. 
