300 



NA TURE 



[July 26, 1906 



do not fj^et malaria, yellow fever, &c., from the water 

 of pooLs or marshes. 



The author in this report emphasises the necessity 

 for the knowledge of these facts, for, as he points 

 out, it is useless to expect an intelligent carrying-out 

 of prophylactic measures by those ignorant of the 

 present state of our knowledge, or bv those who have 



fact, in any col- 



:.— Operations in yellow fever prophylaxis 



outhouse completely closed with paper. 



a " conscientious belief " that malaria is due to 

 marshes and yellow fever to digging the soil. 



The Stegomyia fasciata is essentially a domestic 

 mosquito, i.e. it frequents houses, it breeds in 

 domestic utensils, pots, cisterns, tubs, tins, cala 

 bashes, boats, flower-pots, &c., ir 

 lection of water about a house. 



The destruction of larvae is, 

 therefore, a comparatively simple 

 matter, and if the water were 

 emptied out, thousands of potential 

 mosquitoes would be at once de- 

 stroyed. Where it is impossible to 

 empty any collection of water, then 

 the simple device of covering the 

 receptacle with suitable gauze has 

 the same effect. So that the de- 

 struction of larvae of Stegomyia can 

 readily be effected if only people 

 will or can be compelled to do it ! 



We may e.xpress some doubt, 

 however, as to what would happen 

 supposing Stegomyia suddenly by 

 some governor's edict found all 

 their breeding tubs emptied of 

 water or covered over. Would 

 they be content to die, or would 

 they now breed in ditches, canals, 

 slowly-flowing streams, &c., as 

 -\nophelinEe do? We think they 



would choose the latter course, and this point is 

 not solely of academical interest, for the most 

 vigorous campaign against tubs and cisterns might 

 liave been carried out, and yet the Stegomyia 

 might now be enforced to breed in drains, canals, 

 &-C., and if these existed in the midst of the 



town it is conceivable that the condition of things 

 might be no better than before. For the doing away 

 with canals, &c., implies drainage and re-levelling, 

 and is a far more expensive matter than mosquito- 

 destroying in back-yards. But no considerations of 

 this kind should restrain us from doing our utmost 

 absolutely to free a town of its tub-bred larvae, and 

 that this is possible is shown by experience at Havana 

 and New Orleans. 



Not only must the larvae be proceeded against, bul 

 also all adult mosquitoes, and that this is not the 

 impossible task it might at first sight appear has 

 also been shown by the Americans. 



By very simple means, by pasting up a house with 

 sheets of paper, and by the use of a suitable fumi- 

 gating mixture (camphor and carbolic acid), not only 

 rooms, but outhouses and sheds can be expeditiously 

 and completely freed from mosquitoes. 



By these means the epidemic of yellow fever in 

 New Orleans of 1905 was rapidly brought to an end. 

 The history of the epidemic shows what can be done 

 li\ systematised effort supported by the intelligent 

 cooperation of the whole of a city. 



The present very able and comprehensive report 

 sets out at length the conditions prevailing in British 

 Honduras, showing how in Belize, the capital, and 

 other towns all those conditions exist which in the 

 light of our present knowledge should not exist. 

 StL'go)nyia fasciata exists in profusion, and breeds 

 freely, and so far without hindrance, in water vats, 

 tanks, wells, barrels, tins, and a multitude of other 

 receptacles. 



In considering the origin of the outbreak of the 

 disease in British Honduras, the author adopts the 

 view that the disease was imported, and does not 

 discuss another possibility. It is well known, how- 

 ever, that among the native population in yellow- 

 fever areas the children suffer from extremely mild 

 attacks of fever, and, indeed, many of these cases 

 are not recognised as such. By this means an en- 

 demic supply of yellow fever may always exist, and 

 it may be only at some years' interval that the disease 

 breaks out again in epidemic form. 



.'\part from this, however, the outbreak of the 

 epidemic is minutely traced, and the difficulty of 



Fig. 2. — House in 



detection of early cases, and the resulting fatality 

 under such conditions, emphasised. 



The necessity for efficient sanitary survey, especially 

 in the matter of breeding-places, is pointed out. 



Finally, we have a complete account of the influence 

 on shipping and disturbance of trade of such an out- 



NO. I 91 7, VOL. 74] 



