TYPHOID BACILLUS ?nl 
agglutinins may persist for several years. ^ The amount of agglutina- 
tion present, as indicated by the degree of dilution which will still 
clump typhoid bacilli, has no known relationship to the severity of the 
attack. An occasional mild case of typhoid may be accompanied by 
the appearance of agglutinins of great potency; severe attacks may 
exliibit little or no agglutinin in the blood. Occasionally, agglutinins 
are not demonstrable in the blood serum of undoubted cases of typhoid 
fever. This has been found to be the case by Moreschi- in several 
cases of chronic leukemia. Moreschi'' has made the interesting observa- 
tion that even the vaccination of these leukemics with killed cultures 
of typhoid bacilli may not lead to the development of agglutinins. In 
icterus an agglutination is not infrequently encountered even if the 
serum is highly diluted. It is very probable that at least some of these 
cases are typhoid carriers, having typhoid bacilli in the gall-bladder. 
They may be ambulatory cases. It has been claimed by some observers 
that the agglutination seen in icteric patients is due to bile in the blood 
stream. This, however, has not been proved. A negative agglutina- 
tion, when the clinical symptoms suggest typhoid fever, should indicate 
the possibility of a paratyphoid infection. Sometimes the serum of a 
typhoid patient will agglutinate a culture of B. paratyphosus as well. 
It must be remembered that vaccination with typhoid bacilli will 
result in the production of specific agglutinins. The vaccinal history 
of the patient should alw^ays be elicited. 
Ophthalmo /?eaf^io?2. — Chantemesse^ has found that an ojihthalmo 
reaction may be elicited in typhoid patients similar to that produced 
by the introduction of tuberculin in the eye of the tuberculous patient. 
Broth culures of typhoid bacilli are precipitated with alcohol; the 
precipitate is dried and pulverized; 5V "^S- o^ ^^^^ powder is dissolved 
in a few drops of sterile saline solution and introduced into the eye. 
A transient redness with a flow of tears occurs in normal individuals; 
a severe reaction (even accompanied by a serofibrinous exudate in 
unusual cases), which reaches its maximum intensity within twelve 
hours, is elicited in typhoid patients, and, occasionally, in individuals 
who have recovered from the disease. The diagnostic value of the 
reaction is as yet undeterm ned. 
Dissemination and Prophylaxis.— The disease typhoid fever occurs 
only by transmission of typhoid bacilli directly or indirectly from 
preexisting cases. The disease is acquired only by the ingest on of 
the specific organisms, and infection by any other channel than the 
alimentary canal has not so far been satisfactorily demonstratefl. 
Prophylactic measures, therefore, should begin with the isolation 
of the patient and disinfection of all excreta and a 1 utensils wh ch 
1 An initial negative reaction (first week) followed by a positive reaction is conclusive. 
It rules out the possbility of persistent agglutinins from previous cases, and those due 
to protective vaccination. 
2 Ztschr. f. Immunitatforschr., orig., 1914, 21, 410. ^ Loc. cit. 
IV Internat. Cong. Demog. and Hyg., Berlin, September 26, 1907. 
