The Prevention of Malaria in Hong Kong, by J. M. 

 YOUNG, M.B., F.R.C.S.Ed.* 



The prevalence of malaria in the island of Hong Kong has not 

 only been demonstrated by finding the various types (both benign and 

 malignant) of the malarial parasite in the blood of patients, but also 

 by whole districts mapped out as notoriously unhealthy, houses after 

 being built standing uninhabited, whole terraces unletable, and having 

 to be pulled down, because of the amount of fever from which the 

 inhabitants suffered. For six months under the military and civil 

 authorities I made extensive experiments over considerable areas, with 

 the object of finding out the cause and making suggestions as to the 

 prevention of malaria. 



Alike from adult mosquitoes secured and examined and from 

 larvae collected from various breeding pools and developed in captivity 

 two distinct varieties of Anopheles are abundant Anopheles costalis 

 and Anopheles sinensis^ and nearly a dozen distinct species of Culex^ 

 the proportion of Anopheles varying in different localities. 



The localisation of the various Anopheles breeding pools around 

 twenty selected districts where malaria had distinctly and repeatedly 

 manifested itself gives some important information as to the range 

 of an infected area from a given nidus. From these I have chosen 

 six, of which I give full details and measured distances, with rough 

 sketch maps. 



i. THE MILITARY SANATORIUM. 



An isolated building, with accommodation for two companies and 

 officers' quarters, situated on the hillside above Hong Kong City. 

 The history of this building is most instructive. Three years ago, 

 owing to the prevalence of malarial fever of a most malignant type 

 (80 per cent, of the last company sent there being down with malaria) 

 the building had to be closed. This valuable property had assumed 

 a most deserted appearance, the trees, shrubs, and grass having 

 grown up all over the hillside. 



* British Medical Journal, 1901, vol. II., page 683. 





