232 BACTERIA, YEASTS, AND MOLDS 



In a few diseases characterized by coughing the germs are 

 distributed by air from the mouths of the patients. The 

 most noticeable of these are consumption (Fig. j"]), whoop- 

 ing cough, and very likely measles at certain stages. The 

 air coughed from the mouth in these cases contains small 

 particles of moisture which float around for some time, 

 and these particles are likely to be laden with disease 

 germs. As long as this water is floating the air may be 

 dangerous to another person breathing it. In these cases 

 also the danger is practically confined to the immediate 

 vicinity of the patients, for these particles 

 of moisture do not float very long but soon 

 sink to the ground or come in contact with 

 the walls of the room. Danger is confined 

 to within a few feet of the patient, a dis- 

 tance as great as that of the next room 

 of tubercu^olis"^ being usually sufficient to free the air from 

 such floating microorganisms. The only 

 way to avoid such dangers is to insist upon plenty of fresh 

 air in the sick room, and to air the rest of the house 

 frequently and thoroughly. 



Tuberculosis (Fig. T]), or consumption, has a special 

 source of danger in the sputum of the patient. This 

 material is filled with the dangerous bacilli. As long as 

 it is kept moist they have little chance of distribution ; but 

 if the sputum is voided on the floor or where it can dry, 

 the dried material will blow around as dust, still contain- 

 ing active bacilli. The sputum of consumptive patients 

 should be received in old cloths which can be burned, 

 thus destroying all danger, or in special cups which can 

 be sterilized by disinfectants. 



