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THE AGRICULTURAL NEWS. 



August 11, 1917. 



"the first year of life, gastro-intestinal diseases increase 

 in destructive power, which, in a large measure, is due 

 to contaminated milk and improper methods of feeding. 

 The consequent enormous loss of life is of grave concern 

 to the West Indies, the development of many of the 

 islands being retarded by an insufficient labour supply. 

 The best manner to solve this problem is to reduce the 

 ravages of disease, especially when it can be controlled 

 effectively by personal and combined action. 



Many deaths caused by the transmission of germs 

 l)y flies are preventible by the expedient of so reducing 

 the prevalence of the fly as to render it unimportant as 

 a factor in causing disease. Experience has, however, 

 shown again and again, that it is useless to expect to 

 meet this problem successfully by attempting to kill 

 individual flies, as will be readily understood from a 

 study of the life-history of the fly. The egg of a fly, 

 laid in garbage, hatches in a few hours under 

 favourable conditions into a grub, which in five days 

 turns into a chrysalis, and in another five days the fly 

 appears. One female fly will lay one hundred and 

 twenty eggs at a sitting and in a few weeks can have 

 millions of descendants. As the extermination of flies 

 by individual destruction is out of the question and as 

 flies are essentially the product of filth and dirt, the 

 most effective mode, therefore, of dealing with them is 

 the removal of the sources necessary to their existence- 



In towns supplied with pipe-borne water and 

 -with a proper sewerage system, typhoid fever should, 

 if the sanitaryauthciriiies are alive to the importance 

 of their duties, be derivable solely from outside causes, 

 •such as contaminated inilk from the countrj% the 

 Yeiurn of persons from less sanitary districts, and lack of 

 care in the disposal of the sources of infection from 

 those who have contracted typhoid fever from the first 

 ^wo causes. Although several West Indian towns have 

 ■sewerage system and most have the tap system for 

 their water-supply, the inhabitants cf the islands may 

 be regarded as living strictly under agricultural 

 conditions. The danger of the germs of the disease 

 being conveyed to food supplies by flies is manifest, 

 when it is considered how many favourable breeding 

 places they can find i>i manure heaps and stables, 

 besides having ample opporiimities for development in 

 .the defective sanitary arrangements of many houses. 



With regard to manure heaps, precautions should 

 be taken to prevent their existence longer than is 

 absolutely necessary. As much as possible they should 

 be removed far away I'rom dwellings or they should be 

 covered with a few inches of earth or sprinkled with 

 some antiseptic solution. There is no gain to the 

 jplanter to allow pen manure to be exposed to the atmos- 



phere. On many estates the manure is allowed to lie 

 about until a very large part of it is 1 ist. It is calcu- 

 lated that exposure to the air results in a short time 

 in a loss of half its value. Cleanliness in the stables 

 is also a large factor in the health of horses and 

 consequently in their working etficiency. Were syste- 

 matic measures taken in the West Indies to remove, as 

 far as practicable, these fertile breeding places, 

 the number of flies would be sensibly diminished, 

 and the result would add not only to the comfort 

 but also definitely to the health and safety of their 

 inhabitants. 



It is naturally out of the question to suppose that 

 flies will be entirely exterminated by the partial removal 

 of their breeding places on estates, and efforts must 

 therefore be made by every person to keep houses and 

 yards scrupulously clean. Dust receptacles should be 

 emptied regularly and no refuse should be allowed to 

 lie about, while it is important to screen food supplies 

 so as not to attract flies. In cases of sickness, stringent 

 precautions should be taken to disinfect all deposits. 

 Fly-poisons for out-door and indoor use (especiall}' in 

 hospitals) are frequently necessary. In Mesopotamia, 

 the method of poisoning flies by exposure of sodium 

 iirsenite with sugar yielded good results, and in hot 

 climates wh* re flies come readily to sugar solutions, their 

 use as an outside poison is especially effective. As 

 however, there are obvious disadvantages, owing to their 

 poisonous properties, in using arsenic solutions, import- 

 ant investigations, the results of which will shortly be 

 made known, are being conducted at the Imperial 

 College of Science and Technology of London to find 

 substitutes equally serviceable. So far as laboratory tests 

 can help, these show that there are substances other than 

 arsenic which can kill flies. Fluorides and iodates 

 used at 1 per cent, in sugar solution and not in any 

 way dangerous or offensive, have been proved to be 

 excellent for indoor use. In hospitals, particularly, 

 the small quantity required makes even the salicylates 

 possible as useful fly poisons, an ounce of salicylate to 

 five pints of water poisoning flies for some time 

 throughout even large hospitals. The fluorides are in 

 use as indoor fly-poisons in the Imperial College of 

 Science, where they destroy successfully flies that 

 escape to the lavatories from the fly rooms. 



The dangers from flics are too obvious to be 

 disregarded. Medical men are convinced that general 

 measures, combined with individual effort, against flies 

 would result in a great reduction of disease and 

 mortality. The effort is, therefore, well worth making^ 

 and it will be made if the people of these islands come 

 to realize the danger and take t.he measures necessary to 



