bacilli in their throats without manifesting any symptoms of the disease. Non-virulent varieties of the diphtheria bacillus are not infrequently found in the throats of healthy persons. Much attention has been given by bacteriologists to the question as to how long the bacillus may persist in the throats of convalescents from the disease. Drs. Park and Beebe,

FIG. 7.

Bacillus of diphtheria; magnified 1000 diameters.

of the New York Health Department, found in a series of 605 cases that the bacilli disappeared in three days in 304, in seven days in 176, in twelve days in 64, in fifteen days in 36, in three weeks in 12, in four weeks in 4, and in nine weeks in 2. This shows the necessity for expert opinion before one who has recovered from the disease is allowed to associate with susceptible children.

It is now recognised by physicians that "membranous croup" is due to the diphtheria bacillus, and is in fact a form of diphtheria, most common in very young children, in which the larynx and larger bronchial tubes are the seat of infection.

The total number of deaths reported from diphtheria in the last census year (1900) was 28,959. This amounted to 29 in every 1000 deaths from all causes. This is a very considerable gain upon the proportion shown by the census of 1890 (49.7 per 1000). The death-rate per 100,000 of the population was 45.2; in 1890 it was more than twice as great (97.8). This gain is no doubt largely due to the diminished mortality resulting from the specific treatment of the disease with diphtheria antitoxin. The death-rate is more than twice as great in cities as in rural districts. The District of Columbia has the highest rate (75.4); and the State of Vermont the lowest (18.3). It is evident that, in view of our previous statement that the mortality is greater in cities than in rural districts, it is not fair to compare the District of Columbia with States having a large rural population. As compared, however, with the average rate for cities (52.8) the record of the capital city of the nation is not creditable. It is due to the large coloured population of the city and the comparatively large death-rate among negroes as

compared to whites. This applies only to children under one year of age (345.7 per 100,000 coloured and 154.9 per 100,000 white); beyond this age the mortality is somewhat greater among white children.

For the prevention of diphtheria it will not only be necessary to disinfect the sputa of the sick and all articles liable to be soiled by it, but also to isolate infected individuals until all danger of their communicating the disease has passed. The measures recommended in the previous chapter for the disinfection of tuberculous sputum apply equally well for diphtheria. The diphtheria bacillus is promptly destroyed by a temperature of 140° Fahr. (60° C.) and by the various germicides heretofore mentioned. Boiling water, for all articles which can be sent to the laundry and for the disinfection of sputa in metal or porcelain receptacles, is the cheapest and most reliable disinfectant, but it will usually be necessary to use a solution of carbolic acid (three to five per cent.), or one of the other coal-tar products (lysol, creolin, tricresol), in the sick-room. Woollen clothing and other articles which would be injured by immersion in boiling water may be disinfected by steam or by formaldehyd gas.

The New York Health Department makes the following judicious recommendations with reference to the prevention of diphtheria:

"If possible, one attendant should take entire care of the sick person, and no one else besides the physician should be allowed to enter the sick-room. The attendant should have no communication with the rest of the family. The members of the

family should not receive or make visits during the illness.

"The discharges from the nose and throat must be received on handkerchiefs or cloths, which should be at once immersed in a carbolic solution (made by dissolving six ounces of pure carbolic acid in one gallon of hot water, which may be diluted with an equal quantity of water). All handkerchiefs, cloths, towels, napkins, bed linen, personal clothing, night-clothing, etc., that have come in contact in any way with the sick person, after use should be immediately immersed, without removal from the room, in the above solution. These should be soaked for two or three hours, and then boiled in water or soapsuds for one hour.

"In diphtheria and scarlet-fever, great care should be taken in making applications to the throat or nose, that the discharges from them in the act of coughing are not thrown into the face or on the clothing of the person making the applications, as in this way the disease is likely to be caught.

"The hands of the attendant should always be thoroughly disinfected by washing in the carbolic solution, and then in soapsuds, after making applications to the throat or nose, and before eating.

"Surfaces of any kind soiled by the discharges should be immediately flooded with the carbolic solution.

"Plates, cups, glasses, knives, forks, spoons, etc. used by the sick person for eating and drinking must be kept for his especial use, and under no circumstances removed from the room or mixed with similar utensils used by others, but must be washed in the room in the carbolic solution and then in hot soapsuds. After use the soapsuds should be thrown into the water-closet and the vessel which contained it should be washed in the carbolic solution.

"The room occupied by the sick person should be thoroughly aired several times daily, and swept frequently" (we think it better to wipe floors with cloths wet with a disinfecting solution),

"after scattering wet newspapers, sawdust, or tea-leaves on the floor to prevent the dust from rising. After sweeping, the dust upon the woodwork and furniture should be removed with damp cloths. The sweepings should be burned and the cloths soaked in the carbolic solution. In cold weather the sick person should be protected from draughts of air by a sheet or blankets thrown over his bed while the room is being aired.

"When the contagious nature of the disease is recognised within a short time after the beginning of the illness, after the approval of the Health Department Inspector, it is advised that all articles of furniture not necessary for immediate use in the care of the sick person, especially upholstered furniture, carpets, and curtains, should be removed from the sick-room.

66

When the patient has recovered from any one of these diseases the entire body should be bathed and the hair washed with hot soapsuds, and the patient should be dressed in clean clothes (which have not been in the room during the sickness) and removed from the room. Then the Health Department should be immediately notified, and disinfectors will be sent to disinfect the room, bedding, clothing, etc., and under no conditions should it be again entered or occupied until it has been thoroughly disinfected. Nothing used in the room during the sickness should be removed until this has been done."

Where the parents have not ample means to provide for the services of a trained attendant, and a suitable room for the isolation of the patient, it will be much better for the sick person, and for all concerned, to send the patient to a contagious-disease hospital, when this is practicable. The diphtheria bacillus resists desiccation for a long time and rooms or clothing soiled with material containing this deadly disease germ remain dangerous for months if they have not been properly disinfected.