Leeches.
Persons travelling in India, Ceylon, the Far East generally, and the Philippine Islands, are likely to make the acquaintance of the Asiatic leech, which is a very troublesome and indeed dangerous species of vermin. It is very small, only about an inch long, and of the thickness of a knitting-needle. It is able to penetrate through the interstices in clothing, and when in vast numbers it is a foe difficult to combat. The bites of these leeches are painless and much blood may be lost before their presence is discovered. It is very difficult to obtain any kind of boot or puttee which will keep these creatures at bay, and the traveller in these countries should be provided with a solution of salt or weak acid which, on application, causes the leeches to loose their hold. It is a mistake to try and drag them off the skin, as parts of their biting apparatus are apt to be left behind and set up inflammation and suppuration. Tincture of iodine should be applied to the site of a leech bite. In forest regions where these leeches abound protective measures must be taken at night, the best being the use of a properly adjusted mosquito net of very fine mesh.
The tropical water leech is found in the Azores, the Canary Islands, Africa, Palestine, Syria, Armenia and Turkestan. It may reach a length of four inches, and if swallowed with drinking water usually fastens on the mucous membrane of the mouth or throat. As a preventive measure drinking water should be passed through a piece of muslin or similar form of sieve.
Leishmaniasis.
This condition is named after Sir William Leishman, who discovered the parasite producing it. There is a general and febrile form of the disease and also a form attacking the skin and mucous membrane of the mouth and nose, which is considered under Skin Diseases.
The systemic form of the disease is commonly known as kala-azar, which signifies “black sickness.” It is common in certain parts of India, notably Assam, but is found also throughout the Far East, and it occurs in Arabia, in the Anglo-Egyptian Sudan and in the Mediterranean area. A case has also been described in South America, in parts of which it is possibly more common than is generally supposed.
Cause.—The parasite, which lives in the blood and tissues, is known, but its exact method of transmission to man is still in the realm of uncertainty.
Symptoms.—The disease begins in an indefinite manner and then assumes the form of a continued fever, associated with enlargement of the spleen and liver and progressive emaciation. Bleeding from the nose is not uncommon, and in Europeans the peculiar earthy-grey colour of the skin is very striking. The disease lasts for months and even years and is very frequently fatal.
Prophylaxis.—As we do not know how the disease is spread it is not easy to recommend preventive measures, and all that can be said is that every care should be taken to isolate the sick, to live under healthy conditions and to avoid contact with vermin of all kinds. As dogs may possibly be carriers of the disease they should be destroyed if proved infected.