50 



30,000 inhabitants, where half the children and many of the 

 adults are infected, as in Freetown, the cost of providing 

 the requisite medical staff and the drug itself (quinine) 

 would be very great.* (4) Under British law it is im- 

 possible to force people to take any prophylactic drug, 

 and we may be sure that nine-tenths of the people in 

 any British colony would absolutely refuse quinine. (5) 

 Quinine does not cure yellow fever or destroy filariae ; 

 hence this method would protect against only one out of 

 the three mosquito-borne diseases. 



Segregation of Etiropeans is the last measure recom- 

 mended, and is evidently an excellent one as regards all 

 diseases. The good health enjoyed by the British in most 

 Indian stations is probably largely due to the fact that 

 they live apart from the natives in separate cantonments. 

 Unfortunately segregation will in many cases necessitate 

 the construction of fresh settlements at a large cost ; it will 

 protect only the persons who are segregated ; and then 

 only if such persons absolutely refrain from going into 

 other parts of the town.f It will often be very difficult for 

 business men to adopt this measure. 



If we study these remarks carefully we shall scarcely 

 fail to be convinced that for large towns, at least, the 

 extirpation of mosquitoes is the measure which presents by 

 far the greatest advantages. It is, indeed, probably the 

 only one which will be ultimately found practicable for 

 reducing mosquito-borne disease on a large scale in towns ; 

 and, in fact, the good effect of drainage against malaria has 

 been known for generations. The other methods are more 



* I am informed that in Lagos the annual quinine bill alone will amount 

 to ^500 a year. 



f- In West Africa it is probable that many of the worst infections are 

 acquired by Europeans in the houses of natives. Verbum sat sapienti. 



