514 THE POPULAR SCIENCE MONTHLY. 



the disease is diphtheria. Some of the material from the sus- 

 pected person's throat is obtained by rubbing the latter with a 

 rod having a piece of sterilized cotton wound around its end, and 

 then the cotton is rubbed over a sterilized mixture of blood- 

 serum contained in a closed test-tube, so as to transfer any micro- 

 organisms from the cotton to the serum. The test-tube is placed 

 in an incubating oven and within twenty-four hours the charac- 

 ter of the growth of micro-organisms may be decided. In one 

 year Dr. Park and his assistant, Mr. A. Beebe, made bacterio- 

 logical examinations of 5,611 cases of suspected diphtheria, and 

 the bacilli of true diphtheria were only found in 3,255 cases, or 

 fifty-eight per cent, twenty-seven per cent of the cases being 

 pseudo-diphtheria, and fifteen per cent being of a doubtful char- 

 acter. This seems to prove conclusively that every case sus- 

 pected of being diphtheria must be examined bacteriologically by 

 an expert. 



The affected person should be regarded as infectious from the 

 moment the diphtheria bacilli are found to be present upon the 

 mucous membranes, and, while the bacilli usually disappear with 

 or soon after the disappearance of the local signs, yet in some 

 cases they may remain in an active and virulent state for weeks 

 and even months after the patient has apparently recovered. 

 Therefore no patient should be discharged as recovered until at 

 least two or three bacteriological examinations, made at different 

 times, have failed to reveal the presence of the Klebs-Loeffler 

 bacillus in the secretions of the air passages. 



Diphtheria is most rapidly communicated by direct contact 

 between the sick and healthy persons. Coughing, sneezing, spit- 

 ting, kissing, holding the patient's hands, the use of utensils in 

 contact with the patient, drink or food in the sick-room, and 

 clothing, books, and toys may be the media for carrying the ba- 

 cilli. From this it may be appreciated that the diphtheria patient 

 must be isolated either in a separate room in the house or in an 

 isolation ward, and that there must be thorough disinfection of 

 all articles in contact with the patient, as well as a local antibacil- 

 lary treatment of the nose and throat to remove the bacilli and 

 thus limit the possibility of their dissemination. 



When diphtheria is prevalent the best prophylactic measures 

 are cleanliness, dryness, ventilation, and proper light in dwelling 

 rooms ; cleanliness of the nose and mouth that may be secured by 

 thorough daily irrigation with a one-per-cent solution of common 

 salt or a two-and-half-per-cent solution of common baking soda, 

 used as hot as can be borne, with careful brushing of the teeth 

 and medical care of the tonsils if enlarged or diseased ; and, finally, 

 cold ablutions of the neck. 



The difficulty heretofore referred to of distinguishing, by the 



