DISINFECTION OF MUCOUS MEMBRANES.

The disinfection of mucous membranes is far more difficult than that of the external integument. Simple irrigation with a disinfectant will not yield the desired result― quite apart from the danger of intoxication. Vigorous brushing, however, and alcohol and ether are naturally not applicable here in the same degree as upon the external integument. The greatest stress is, therefore, to be placed upon mechanical removal of the germs, and this may be effected by brushing and rubbing with the fingers or with swabs of cotton or of gauze. Irrigation of the loosened mucus and debris may be practised with simple warm water, or with nonirritant solutions (weak solutions of boric acid, potassium permanganate, aluminum sulphate, physiologic salt-solution, infusion of chamomile, etc.).

DISINFECTION OF INSTRUMENTS AND DRESSINGS. Metallic instruments are boiled for five minutes in water, preferably after addition of one per cent. of soda, whereby rusting is avoided. Cotton, gauze bandages, and the like are sterilized in the steam-chest or the dry chamber.

DISINFECTION OF FECES AND CESSPOOLS.

Lime is best adapted for disinfection of the stools. In the bed-pan in which the infectious stool (especially in cases of typhoid fever and of cholera) is received, so much milk of lime is previously introduced as will just cover the bottom of the vessel. After defecation an amount of milk of lime is added equal to the bulk of the feces, and the mixture is vigorously agitated and permitted to stand for an hour. The mixture must be highly alkaline (Pfuhl). The milk of lime should always be freshly prepared: To unslaked lime in stone jars or wooden pails so much water is added as will be taken up. The slaked lime is diluted with four times the amount of water.

If chlorinated lime be employed, it must be added in an amount equal to one per cent. of the mixture of urine and feces. It may be added in the form of powder or of a paste

consisting of about twenty grams of chlorinated lime and 100 of water. After thorough admixture the stool need stand for only fifteen minutes.

For the disinfection of cesspools Pfuhl likewise recommends milk of lime. When the tun-system is used, 3 grams = 6 cu. cm. of pulverulent slaked lime, or, better, 30 cu. cm. of milk of lime, and in the case of pits 2 grams 4 cu. cm. of pulverulent lime, or, better, 20 cu. cm. of milk of lime should be allowed daily for each person. The seat as well as the funnel-shaped basin and the discharge-pipe must be thoroughly irrigated with the disinfecting solution. If, in addition to feces, which may be estimated at 400 cu. cm. for each person daily, also the total amount of urine is thrown into the receptacle, the mass of material to be disinfected may be estimated at between 1500 and 2000 cu. cm., and four or five times as much of the disinfectant should be employed for each person. Under these conditions also disinfection is attained only when the privy-contents exhibit a distinctly alkaline reaction.

Of other disinfectants for water-closets, carbolic acid, sulphocarbolic acid, lysol, and saprol, may be mentioned. These must be introduced in solution, and in an amount equal to two per cent. of the material to be disinfected; about eight grams daily may, therefore, be estimated for each person. All of these substances are more expensive than milk of lime, without possessing especial advantages. For hospitals it may be recommended that the entire fecal accumulation be boiled in a suitable vessel with addition of deodorizing substances (potassium permanganate).

DISINFECTION OF BATH-WATER, WASH-WATER, ETC.

Bath-water, when contaminated by patients, is disinfected by means of milk of lime (six liters to a bath of 300 liters) or of carbolic acid. Mercuric chlorid is to be avoided when metallic tubs are used.

Wash-water is freed from typhoid-bacilli and cholerabacilli, according to Pfuhl, within an hour if 1.5 to one thousand of calcium hydroxid be added, and if constant agitation is maintained.

Koch permitted milk of lime to be introduced into the drainage-fluid at Nietleben until the fluid appearing in the

main discharge-conduit at the lower end of the irrigationfield presented a marked alkaline reaction.

For the disinfection of water-conduits dilute milk of lime, carbolic acid, or a mineral acid, is employed. At Nietleben Koch disinfected the service by means of carbolic acid, permitting three per cent. carbolic acid to be driven from the pumping well into all divisions of the service, and to remain in the conduits for twenty-four hours. Then the pipes were irrigated with wholesome water. This procedure is attended with the objection that the water retains for a considerable time the taste of carbolic acid. On the other hand, however, it does not carry with it the danger of obstruction of the conduits that attends the employment of milk of lime.

DISINFECTION OF URINE.

The urine is usually disinfected in common with the feces. It is generally not so infective as the stools. If it is to be disinfected alone, this may be accomplished by addition of milk of lime, carbolic acid, or mercuric chlorid.

water.

DISINFECTION OF SPUTUM.

The sputum must be received and preserved in a moist condition, preferably in sputum-cups containing a layer of So long as the sputum is contained within such cups it is relatively harmless. A greater danger resides in the conversion into dust and into spray of sputum evacuated into handkerchiefs, upon floors, etc. On emptying the vessel the sputum must be disinfected. Crude carbolic

acid (from 5 to 10 per cent.) or mercuric chlorid (1 or 2: 1000) would be suited for this purpose if the disinfectant penetrated the sputum. Generally, however, the albumin on the outer surface of the mass of sputum is coagulated, and the bacilli contained within do not come in contact with the antiseptic at all. For this reason the sputum must at least be thoroughly rubbed up in the disinfecting solution, and remain therein for a long time. Lysol (10 per cent.) and crude solutol (from 5 to 10 per cent.) do not coagulate the sputum, and are therefore better adapted for disinfection. It is further useful to disinfect the sputa by heat. If

they are not too abundant and are at the same time viscid, they can be simply burned in a stove. Otherwise they are introduced, together with the sputum-cup, into a specially constructed disinfector, resembling the steam-chest (Kirchner), in which they are exposed for half an hour to the action of steam at a temperature of 100° C. (212° F.). The apparatus has the disadvantage that a number of the cups will be broken, and in families it can not often be provided. Under such circumstances the sputa can be poured into a pot and boiled for half an hour in water. Usually, however, one will have to be satisfied with simply emptying them into the water-closets, where the pathogenic germs are simultaneously destroyed, in part with the disinfection. of the feces and in part by the process of putrefaction. The sputum-cups should be sterilized by means of hot water and carbolic acid, and preferably likewise boiled.

DISINFECTION OF BODY-CLOTHING AND BED-LINEN.

Uncontaminated linen is boiled for half an hour in petroleum soap-water (two bucketfuls of water-about thirty liters to 250 grams of soft soap and two spoonfuls of petroleum; then, after removal of the soap-water, rinsed in cold. water; next washed with soap in clean hot water; then again rinsed in cold water, permitted to remain over night in clean water, and finally dried in the open air. Instead of this procedure the linen may also be disinfected in the steam disinfecting apparatus.

Contaminated linen requires removal of feces, mucus, or pus before application of heat, as otherwise burned spots will appear. Such linen must immediately after removal be placed in a sheet moistened with mercuric chlorid, 1 : 2000, then in strong, moist sacks, and sent away for disinfection. The sacks, unopened, are introduced into the disinfecting fluid, three per cent. soft-soap solution, in which the linen is treated for three hours at a temperature of 50° C. (122° F.), and then remains for an additional forty-eight hours during the process of cooling; or mercuric-chlorid salt solution (of 0.5 to one thousand mercuric chlorid and 6 to one thousand sodium chlorid). After disinfection in this way the linen is further treated in the same manner as uncontaminated linen.

DISINFECTION OF BEDS AND CLOTHING.

Articles of clothing and beds are best disinfected in suitable apparatus in live steam. If such an apparatus is not available, exposure to air and sun must be resorted to or rubbing with three per cent. carbolic acid. To purify articles by exposure to air, they must be hung for days in a dry room and exposed as uniformly as possible upon all sides to the rays of the sun. Even then the disinfection is not trustworthy. The bedstead, articles of leather, and the like, are rubbed off with five per cent. carbolic acid. For the disinfection of clothing formalin (a forty per cent. solution of formaldehyd) has been warmly recommended. The clothing should be loosely packed in a chest, and between its layers are placed strips of goods saturated with formalin. From thirty to fifty grams of formalin are required for a suit of clothing. Disinfection is said to be completed within two hours, and the disagreeable odor may be removed by means of ammonia.

DISINFECTION OF ARTICLES OF FOOD.

The keeping clean of articles of food is especially a prophylactic measure. These should not be permitted to stand about in the sick-room, but they should be kept covered, Portions of food left unused by the patient are burned, as well as articles of food that are known to have been in

etc.

fected in other ways. Milk and other liquids are drunk only boiled, as should also be drinking-water in times of cholera-epidemic.

DISINFECTION OF THE SICK-ROOM.

A sick-room should not contain pictures, curtains, etc., in fact any superfluous articles that only serve as dust-collectors. After the termination of the illness the room of the patient, and possibly the entire dwelling, should remain undisturbed for about ten hours, to permit the dust to settle, and then it should be thoroughly disinfected. In some large cities this is undertaken by special establishments. Such disinfecting stations should be established everywhere, for