380 REPORT OF THE HARVARD AFRICAN EXPEDITION 
prevailed in the upper Ogowe region in Gabon, where thirty per cent of the in- 
habitants were infected. In the Chad colony the infections were estimated at 
seven per cent of 1,500,000 inhabitants, with an average yearly death rate of 
25,000. In the Cameroons, Tamon and Jamot found that of 100,000 natives 
examined through several years, 30,000 were infected, the percentage of infected 
in the different districts varying from eight to forty-eight per cent. 
In a more recent report of Jamot,! for the Cameroons, it is pointed out that 
from October 1926 to November 1928, 81,063 new cases of infection were seen, 
which makes a total of 115,354 people infected with trypanosomes for a popula- 
tion of 663,971 inhabitants, or an average of 17.46 for 100 inhabitants. On the 
other hand, infection with trypanosomiasis among white people in Africa is very 
rare. Van den Branden 2 (1928) in reporting upon the first medical cruise of the 
hospital ship ‘‘ Belgique”? upon the Congo River between Leopoldville and Kwa- 
mouth, found only one European infected in this region. In all, 3,778 natives were 
examined in 52 villages and 168 new cases of trypanosomiasis were discovered; 
620 cases were also found undergoing treatment. Also, in many parts of Africa 
where sleeping sickness was formerly said to prevail, it is no longer a serious 
problem. Thus Van Hoof, who has made an epidemological inquiry regarding 
the diseases of the Budama district and the Kavirondo north of Lake Victoria 
which involved the examination of more than 45,000 natives, concluded from a 
careful village to village inquiry that sleeping sickness played a distinctly minor 
part in the general mortality as compared with infant mortality, which was still 
the chief obstacle in the development of the races. 
We observed no cases of sleeping sickness in our journey from Yakusu north- 
ward to Lake Edward. The plains of Ruchuru and the Ruindi south of the Lake, 
and the lower country at the northern end as well, are ‘“‘closed”’ because try- 
panosomiasis formerly prevailed there, and it was necessary to obtain special 
permission to enter these closed localities. In the vicinity of the Ruchuru River 
there were many small villages and no cases of trypanosomiasis were recognized 
in them, although no general search was made for it. There is no hospital at 
Ruchuru. The diseases regarded as most common there were malaria and tick 
fever. 
While we were on the plains, between February 2nd and early March, there 
was practically no rain and tsetse flies were seen rarely, except upon game which 
we shot. We left the plains on April 25, after there had been more or less rain 
for six weeks, and tsetse flies were still not abundant. Captain Catchpole, an 
English hunter, said that before the dry season there had been swarms of tsetse 
flies among the bushes along the banks of Lake Edward. Trypanosomes were not 
found in any of the wild game shot in these regions, though blood specimens were 
always taken. 
At New Beni (Bungulu) at the edge of the Semliki Valley, prisoners were 
shown us as suspected cases of trypanosomiasis. Gland palpation and puncture 
were performed and blood smears were also examined and all were negative. 
1 Jamot: Bull. Soc. Path. Exot. (1929), XXII, 481. 
2 Van den Branden: Ann. Soc. Belge Méd. Trop. (1928), VIII, 197. 
