71

A.—s

Filariasis : This mosquito-borne disease is the one which comes most prominently under our nonce in the islands of the South Pacific, and is due to the filaria parasite, a worm-like organism which infests the blood-vessels. This disease is exceedingly prevalent in these islands, and produces conditions ranging from general indisposition of a vague character to the definite condition known as elephantiasis. Men and women may frequently be seen with lower limbs utterly shapeless and somewhat resembling an elephant's foot, the foot having almost disappeared in a mass of dropsical tissue. Operation is the only means of affording relief, but the swelling may form in other parts. The mosquito is entirely responsible for this condition. The parasites in those affected with the disease, even though they do not show any symptoms, are found in huge numbers in the bloodvessels of the skin. The mosquito sucks up this blood, and the parasites penetrating the stomachwalls of the mosquito undergo development in its tissues, and are exuded through its proboscis when it bites its human victim, thus injecting the parasites into a fresh subject. Yellow Fever is not known at present in these islands, but the variety of mosquito which is known to make a habit of carrying this disease, when it gets the chance, is found in large numbers, so that should a case be imported there is every prospect of its spreading. Dengue, on the other hand, is an acute febrile disease very common in the islands, and this is also a mosquito-borne disease. The mosquito, therefore, forms a very important factor in tropical hygiene. The Fly. —There are a large number of varieties of flies found in these islands, and they are one of the greatest pests of these parts and are responsible for carrying many diseases. The fly is particularly prone to settle on ulcerating sores, faecal matter, and decomposing material of every description. It is responsible for carrying trachoma, a very troublesome disease of the eyelids, yaws, and various other diseases, including the Ankylostoma duodenalis (hookworm). Hookworm. —This is a small intestinal parasite whose habitat is the upper bowel. It is a smalNworm with a mouth armed with hook-like teeth, which it fastens into the mucous lining of the bowel, where it firmly anchors itself. It sucks blood, with which it is very wasteful, only extracting the portion that it requires for its sustenance and passing the remainder into the bowel. It produces anaemia of a very severe type, which can only be cured by killing the worm. There is a male and a female worm. The female discharges eggs wholesale. These eggs are passed into the bowel and thus escape from the body. The eggs mature in the f.iecai matter and the embryo passes into the earth where the faecal matter is deposited. The earth itself becomes infected and the infected earth may pass into streams. Muddy water, therefore, is frequently found to contain the embryo hookworm, and it gains access to the body by the drinking of muddy water, by eating earth-soiled articles of food, or the contamination of food through the hands of dirty cooks, or by flies which, alighting on worm-infected human excreta, carry the parasite to food. Another means by which the hookworm gains access to the body is through the skin, especially through the soft tender skin between the toes and fingers. It is necessary, therefore, when working on the land in the tropics to protect the hands, and no one should ever go barefooted in these countries. Children also have a habit of eating earth, and this, of course, is obviously a very dangerous practice. From these facts it is obvious that the disposal of faecal matter is one of importance. The Natives of these islands are very careless with regard to this matter and freely soil the earth in the neighbourhood of their settlements with their deposits. It is necessary that they should be educated in the matter of the proper disposal of faecal matter, and be taught the use of properly constructed fly- and mosquito-protected privies. Naturally the same applies to the white settlements. Wherever possible underground sewerage is desirable, and also a clean, pure water-supply. Yaws (known in Tonga as " tona," in Samoa as " falda Zona." —This disease is very common amongst the Natives, and in its secondary stage produces sores scattered over the body. In some respects it resembles syphilis, and has been looked upon as being a form a syphilis, but it is now generally recognised that it is a separate disease though responding to similar treatment. It is caused by close contact, or carried by flies or other insects. Consumption. —This disease is obviously on the increase, and is due in large measure to the adoption of European methods of dress and housing. The Native in his normal state does not wear clothes other than a loin cloth. Perspiration evaporates as soon as it is formed and he suffers no chill. When, however, he gets into European clothes, to which he is not accustomed, these become saturated with perspiration, remain wet, and he contracts a chill. Also his secretions, instead of being got rid of, are held in contact with his body. Clothing for the Native is not necessary in these warm latitudes, and he is far better without it. He has also adopted European materials in the construction of his houses without at the same time adopting the European model of modern times which allows for efficient and free ventilation. In the ordinary way a Native hut if not open at the sides is walled with reeds through which the air freely passes. In many cases he has built similarly shaped houses with impervious wooden wallsand an iron roof. He does not get the ventilation to which he is normally accustomed. The Native also is inclined to crowd in the houses, and conditions of crowding and ill ventilation predispose to and facilite the spread of consumption. The Native has not learned the dangers also of dealing with his expectoration, and freely spits whenever it is convenient to do so. This is a disease, therefore, to which we shall need to give special attention and which will probably require sanatorium facilities. . . , . . . Leprosy —There are a considerable number of leprosy cases m these islands, but it is not, as common'as generally believed. There are cases in Tonga, and it also exists in Samoa. There are two forms of leprosy, the anaesthetic and the nodular. These may, however, be combined. Leprosy is due to a minute rod-like organism very similar in appearance to the_ tuberculosis bacillus with which it has many points in common. Under the miscroscope it is impossible to