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HoKNE (Capt. J. H.)- Malaria in Wynaad. — Proc. Third All-India 

 Sanitary Conf., Lucknow, January 19th-27th, 1914, iv, pp. 71-74. 

 Suppmt. to Ind. Jl. Med. Research. [Received 6th November 

 1914.] 



The Wynaad has long been regarded as one of the worst fever areas 

 in Southern India, and recently certain tea companies have made a 

 serious effort to grapple with the malaria problem and have sought 

 financial aid from the Government for an antimalarial scheme. With 

 this in view, an investigation was carried out in May and June 1913. 

 A description of the prevailing conditions is given. The country 

 consists largely of a succession of low hills covered with grass or jungle 

 or planted with tea. Between them is a network of swamp, for the 

 most part overgrown w4th jungle and gradually emerging in definite 

 streams. Besides these streams, there are others coming from the 

 hills which are well stocked with various species of small fish in the 

 lower parts of their course. The rainfall is heavy and constant, 

 averaging 100 inches per annum. The maximum hot weather tem- 

 perature seldom exceeds 85° F., and in the cold weather the Wynaad 

 is the sanatorium of Malabar. The fever season lasts from March 

 to May — ^-fchat is, in the hot months — and the prevalence of fever 

 previous to the monsoon is noteworthy and has led some observers 

 to doubt its malarial nature. The disease is said to have diminished 

 in the south-east, where the ground is more open within the last 40 or 

 50 years, but in other parts it breaks out in epidemics and causes 

 serious labour difficulties. The population consists of aboriginal jun;?le 

 tribes, permanently resident, and of traders and their families who 

 reside in villages on the main roads and constantly change 

 their residence. Ten thousand coolies are estimated to be employed 

 in May and June. The adult Anopheles were difficult to obtain, chiefly 

 owing to the nature of the house interiors. The principal species 

 found were A. listoni, A. wiUmori, A. jeyporensis, A. culicifacies and 

 A. rossi. 



Anopheline larvae swarmed, the following eleven species being bred 

 from them : — A. macuUpalpis, A. jamesi, A. kanvari, A. maculatus, 

 A. willmori, A. listoni, A.jeyporensis, A. rossi, A. borbirosfris, A. aitkeni 

 and A. lencosphyrus (elegans). A. maculipalpis and tvillmori were the 

 most abundant and were found breeding chiefly in surface drains and 

 streams in swamps. A. listoni was also common, its chief breeding 

 places being swamps and hill-streams. A. jeyporensis was found in 

 only two places, both weedy pools, one of them a spring in an open 

 field. A. leucosphyrus and A. aitkeni were also scarce ; the former 

 was taken in a shady surface- well in the jungle, the latter in streams. 

 Among CuLiciNAE, Stegomyia scutellaris and Taeniorhynchus were most 

 in evidence. Culex mimeticus was frequently found breeding in swamps. 

 OchJerotatxs {Hulecoeteomyia) pseudotaeniatus, closely resembling Stego- 

 myia fasciata in markings, habits and type of breeding place, was also 

 occasionally taken. 



From tables given of the result of the examination of spleens of 

 children it would appear that the jungle tribes are much more seriously 

 affected than others. 



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