SEnoTHERAPv.—Serotherapy has not as yet shown results warranting any con clusion as to its real merits. While Yer sin's serum, according to Arnold (Med. News, Jan. 1, '98), reduced the mortality of severe cases from SO or 90 to 50 per cent. and that of mild cases from 50 to 10 per cent., other observers, Clemow (London Lancet, May 6, '99), for in stance, do not credit it with beneficial powers. This serum is prepared as fol lows: The subcutaneous injection into horses of a fresh plague-bacillus culture upon agar giving rise to a severe local swelling, ephemeral fever, and an abscess, Yersin resorts to venous inoculation, and thus avoids the abscess-formation. Vio lent reaction follows these injections until, after repeated and stronger doses, immunization is accomplished. Three weeks after the last injection a serum is obtained by venesection that may be used therapeutically. It is important to re member, however, that this serum does not long retain its activity (E. Roux).
Prophylaxis.—The prophylactic meas ures indicated consist, first, of vigorous efforts calculated to antagonize unhy gienic conditions, and, second, of pre ventive inoculations. J. M. Atkinson concludes that, the occurrence of plague being favored by the absence of sunshine and general insanitary conditions, such as obstruction to the free access of light and air to domestic dwellings, the steps to be taken to retard the progress of the disease are (a) general cleanliness and the free admission of light and air to domestic dwellings; (b) the immediate isolation of the sick and those who have been in close contact with the disease; (c) the careful and systematic disinfection of all premises in which cases occur and of latrines.
As to the best methods of disinfection, an exhaustive investigation led Abel (Centralb. f. Bakt., Apr. 24, '97) to con clude that moist heat—i.e., steam—was the most efficacious. Of chemical re agents, the best were 1-in-1000 sublimate in carbol-sulphuric acid, lysol, and chlo ride of lime in 1-per-cent. solution. Car bolic acid proved useless in less than 5 per-cent. strength.
Schultz (Archives des Scien. Biol. de l'Inst. limper. de Med. Exper. a St. Petersbourg, tome vi, No. 5, '9S) found that perchloride of mercury has a most powerful action in destroying the plague bacillus, but its strength depends on the medium in which the bacilli are con tained. To disinfect clothes, etc., they must be thoroughly soaked with the chloride solution, which fact does away with its practical usefulness to a large extent. The addition of hydrochloric acid increases its disinfecting action. Though formalin in solution is 20 times less powerful than perchloride of cury, in the form of gas it becomes a most reliable disinfectant, and is deemed the best for furniture, clothes, etc., espe
cially as it injures them in no way.
Experiments showing that the dura tion of vitality of the plague bacillus in the bodies of buried animals continues from twenty-two to thirty days. Yokote (Centralb. f. Bakt., xxiii, p. 1030, '93).
Cases of plague should be immediately isolated; the sputum, urine, and excreta should be received in vessels containing mercuric chloride of the strength of 1 part in 500, while a solution of half this strength should be used for soaking soiled clothes, disinfecting cups, spoons, etc., and washing the physicians' and at tendants' hands. No infected matter should be thrown into the drains on ac count.of the likelihood of infecting rats in the sewers. If patients die, they should be wrapped in sheets soaked in strong bichloride solution, and the body be surrounded in the coffin by carbolized sawdust. W. J. Simpson (Brit. Med. Jour., Sept. 16, '99).
The prophylactic fluid of Haffkine has been extensively used, apparently with encouraging results. In its preparation a luxurious crop of plague organisms is cultivated by adding to the nutritive media abundant quantities of fat exposed to free aeration. The fat used is clarified butter, which is suspended on the surface of the nutritious fluids. When the fluid is filled with a rich jungle of stalactites, the growth is shaken off from the drops of butter and brought down to the bot tom of the liquid, leaving the butter on the surface free to produce a second crop of growth. In the course of a month, half a dozen successive crops are thus ob tained, which fill the liquid, when shaken, with an opaque, milky emulsion. The micro-organisms in this fluid are killed by exposing them for one hour to a tem perature of 70° C. In a quiet position in test-tubes two different substances are then obtained: a thick white sediment and a perfectly limpid fluid. injected subcutaneously into animals they pro duce: (1) the sediment,—a local inflam mation, and a nodule at the seat of in oculation, accompanied by little fever or general effect; and (2) the fluid,—a siderable rise of temperature, and a eral affection, with no noticeable local effects. (Haffkin e.) The injection of 3 cubic centimetres of prophylactic seems to be sufficient to fect the desired protection. It cannot arrest symptoms already started or that show themselves within a few hours, but the time necessary for it to produce the protective effect is very short.