PROPHYLAXIS IN INTESTINAL PROTOZOAL DISEASES 261 



African tick fever is carried by one of the Argasine 

 ticks, Ornithodorns moubata. It bites mainly at night and 

 only persons who are at rest ; and so the usual time of 

 infection is during the hours of sleep. In a bed well 

 raised from the ground and not in contact with the walls, 

 there is little probability of infection unless these ticks are 

 present in the bedding. All bedding should be carried 

 in a tin box and not deposited on the ground of a rest 

 house or native hut at any time, and the ticks will not 

 gain access to the bedding. As the ticks of the second 

 and third generation are infective, it is well to act as if all 

 the ticks of this species were infective. 



Dry dust is the preferential haunt of these ticks. In a 

 well-kept, well-built European house they should not be 

 present. 



Indian relapsing fever is probably carried by Pediculi. 

 Cleanliness of body, hair and clothing is the best pre- 

 ventive. 



Prophylaxis as regards intestinal protozoa requires 

 suitable measures for the destruction and disposal of 

 excreta, good uncontaminated water supply and protec- 

 tion of the collecting area, roof or otherwise, from dust. 

 Food, milk, &c., must also be protected from dust, even 

 after it has been cooked or boiled. 



