J R Army Med Corps: first published as 10.1136/jramc-02-01-10 on 1 January 1904. Downloaded from 64 SURRA. THIS short notice of surra is written in order to induce R.A.M.C. officers living in surra districts to assist in filling up a few gaps in our knowledge of this disease. It is true that surra is not a human disease, but it is none the less of very great importance from an Army point of view; as a force which has to operate in a surra district may lose the greater part, if not all, its transport and riding animals, with disastrous results .. Surra generally occurs in hot climates and in low-lying, damp localities, hence a large number of sick men may be expected coincidently with the appearance of surra, and the question of trans­ port is certain to furnish a good deal of anxiety for the medical officer. In this way surra may closely concern us. Moreover, Leishman's recent observations on the spleens of men dying of Dum Dum fever suggest the possibility of another trypanosome Protected by copyright. disease, in addition to sleeping sickness, occurring in man, so that any fresh information as to the method of spread of trypanosome diseases in general will be of value. \ The disease is a parasitic one caused by the Trypanosoma Evansi. The characteristics of the disease are, progressive wasting and muscular weakness, associated with irregular fever. The disease has been known in India for centuries, but its actual cause was only discovered in 1880 by Evans, a veterinary surgeon. Distribution.-The information available as to the distribution of surra is not very extensive, and later researches will probably http://militaryhealth.bmj.com/ show that its epidemic distribution is much more extensive than is indicated here. The dise'ase usually appears during the rainy season and disappears gradually with the advent of the cold, dry weather. The places in which surra is reported to occur annually are mostly situated close to swamps, or alongside rivers, and are liable to inundations during the rains. The accompanying map shows roughly the area in which it has been reported to occur, although it probably has a much wider distribution. Lingard says it is confined to a belt lying between 18° and 34° N. Lat. on September 30, 2021 by guest. Susceptible Animals.-The horse and mule are most susceptible to surra, the dog coming next-these three practically always suc­ cumbing to the disease. '1'he camel is supposed to live for three years after being infected, while the ox generally recovers after some five or six months. J R Army Med Corps: first published as 10.1136/jramc-02-01-10 on 1 January 1904. Downloaded from Surra 65 Infecting Agent. - Lieut.-Col. Bruce, F.R.S., R.A.M.C., has shown that two other trypanosome diseases,- viz., nagana and sieep­ ing sickness, are transmitted by means of a tsetse fly, the parasite undergoing no change in the insect, but merely being carried from an infected to a healthy animal. As nagana closely resembles surra in its clinical course, and the two parasites are very similar in appearance, it does not seem unreasonable to suppose that the in- Distribution of Surra in India and Burmah. Protected by copyright. J. http://militaryhealth.bmj.com/ 10 Endemic Area.s-..... -. Endemic Centres + Occa.sional outbreaks 0 70 80 fecting agent is also similar. Up to the present no tsetse fly has been found in India. Rogers made some experiments to see if the on September 30, 2021 by guest. infection is carried by the common horse fly, but the results of his work rather negative this. Now, one point we wish to clear up is," What is the infecting .agent in Surra?" In rats the Trypanosoma Lewisii is said to be 5 J R Army Med Corps: first published as 10.1136/jramc-02-01-10 on 1 January 1904. Downloaded from 66 Surra carried by rat fleas; in Nagana the Trypanosoma is carried by the Glossi'l.la morsitans; in Sleeping Sickness the Trypanosoma Gambiense (?) is transmitted by Glossina Palpalis; in Dourine the T'rypanosolna Rougeti is said to be conveyed in the act of coitus. How is Trypanosoma Evansi carried from the infected to the healthy animal? We would be greatly obliged to any R.A.M.C. officer living in a surra district who would try to clear up this point. In searching for the carrying agent we would suggest that some such line as the following might be tried :- In a surra district try to make out what blood-sucking insects are present. In nagana there would be no difficulty in determining which fly is to blame, as the tsetse fly is found in great numbers in the fly-belt and not outside it. Now, having a suspicion that a certain fly carries the infection, catch and imprison as many as possible in small cages made of wood, mosquito netting and glass. The following drawing represents a cage suitable for this purpose, and a useful size is 6 x 3i x 3i in. As will be seen from the drawing five-sides are covered with mosquito netting, and one end Protected by copyright. is occupied by a sliding glass door. Through the glass doo't' the flies can be readily examined. GLASS http://militaryhealth.bmj.com/ A useful box for taking into the field in which to place the newly-caught flies may be made something like the following draw­ ing. It is best to make these catching boxes the same size as the cages to facilitate the transference of the flies. It will be seen from the drawing that both ends and two of the sides are of wood, one end is perforated by a hole !-in. in diameter and plugged by a cork. It is through this hole, of course, that the flies are introduced after being caught. The other end is a sliding door fixed by a screw on September 30, 2021 by guest. in order that it will not accidentally fall out, and to prevent a native <;arrier playing with it. When changing the flies from the catching box to the cage, place the two boxes with the door ends facing each other, and round the two an indiarubber band; raise the two doors J R Army Med Corps: first published as 10.1136/jramc-02-01-10 on 1 January 1904. Downloaded from Surra 67 but do not pull them quite out, and with a little noise of hitting the box with your hand the flies will move into the cage. The flies are most easily caught by means of a small butterfly net with a diameter of 4 to 5 inches, and having a short handle. Having secured the flies, do not let them feed for a couple of days. Then apply the cages to a diseased surra animal, and make a note of how many flies feed. Keep each cageful of flies unfed for various periods, say eight hours, twenty-four hours, forty-eight hours, after which let the flies feed on separate healthy animals, pro­ bably dogs would be most easily obtained. The dog's blood must, of course, be previously examined and found to be free from trypano­ somes. The animal experimented on should also be in a healthy district away from a surra locality, so as to avoid the chance of infection reaching it by other channels. In Zululand we kept our animals on the top of a hill and sent down to the low country at the foot for the flies. Protected by copyright. WOODEN DOOR The temperature of the animal must be taken twice a day, and the blood examined frequently for trypanosomes, especially when any rise of temperature takes place. http://militaryhealth.bmj.com/ Any blood-sucking insects sent to the editor will be examined and named, and it may be remarked that as blood-sucking flies other than mosquitoes are becoming daily of more importance, it would be doing valuable work if our officers stationed all over India would collect and send here any specimens which occur in their neighbourhood. A list of such flies could be given in the Journal with the donor's name opposite. Flies when caught may be placed in cigarette or other tins, with a little cotton-wool to prevent damage in transit, and some powdered naphthaline to on September 30, 2021 by guest. preserve them. • .