1910. | Reservoir of the Virus of Sleeping Sickness. 325 
ditions, each antelope was kept under observation for a week or two before 
any experiments were undertaken. During this time they were well fed 
and comfortably housed in reed kraals erected in a fly-proof house. Some 
of the antelope, especially the “oribi” and “entalaganya,” died during the 
first fortnight. ‘The 11 survivors were the subjects of these experiments. 
Nine of these buck were kept under daily observation for four months 
after becoming infected with Trypanosoma gambiense. They remained 
apparently in perfect health. 
The remaining two antelope were reed-buck. One, Experiment 2429, 
lived, and appeared very healthy, for 93 days after its infection. It then 
accidentally broke its leg and had to be killed. A post-mortem examination 
was made, and no evidence of trypanosomiasis was found. The other buck, 
Experiment 2445, arrived at the laboratory in a poor state of health, and 
died 12 days after its infection. There was no sign of trypanosomiasis at the 
post-mortem examination. 
It is therefore evident that antelope infected with the virus of Sleeping 
Sickness may live in apparently perfect health for at least four months, 
and this, though they be kept under conditions less favourable than would 
occur in nature, the constant handling and fly feedings to which these buck 
were subject being borne in mind. 
5. Are Antelope Living in the Fly-Areu Naturaliy Infected with Sleeping 
Sickness ? 
Positive evidence on the last query would complete the chain of evidence 
that antelope living in the fly-areas may act as a reservoir of the virus 
of Sleeping Sickness. So far it has only been proved that they are 
“potential ” hosts. 
The only method by which this query can be investigated is by capturing 
game in the fly-area and then— 
1. Injecting its blood into animals susceptible to Trypanosoma gambiense 
infection. 
2. Feeding cages of clean laboratory-bred Glossina palpalis on the newly- 
killed buck and subsequently endeavouring to infect animals susceptible to 
Trypanosoma gambiense with these flies. (The Commission know by 
observation that Glossina palpalis will feed readily on animals newly 
killed.) 
Those who know the local conditions will appreciate the difficulty of 
carrying out these methods of investigation. It would be necessary for 
large drives of the buck to be organised in the Hy-areas. Several hundred 
2B 2 
