674 PATHOGENIC MICROORGANISMS 



mild intestinal disease, without, or with very slight febrile manifesta- 

 tions, and the investigations of many bacteriologists, as well as our own, 

 show that a considerable percentage of these people were actually 

 infected with organisms of the typhoid, paratyphoid, and dysentery 

 groups. 



As to the relative importance of the typhoid carrier in the morbidity 

 of typhoid fever, it is very difficult to adduce accurate data. It is 

 pretty safe to say that the carrier is growing relatively more important, 

 will in the future probably be the chief source of typhoid morbidity 

 in well sanitated communities, and is the only stumbling block which 

 will probably prevent the complete eventual eradication of the disease. 

 Of recent years, as water, milk, and food supplies are coming more and 

 more directly under the vigilant eyes of health authorities, the estimates 

 of the percentage of cases due to carriers, as contrasted with other 

 sources of infection, is growing larger and larger. 



PATHOLOGICAL CONSEQUENCES OF THE CARRIER STATE. Perhaps 

 the most common sequelum of the chronic carrier state is cholelith- 

 iasis. According to Exner and Heyworski 94 typhoid bacilli have a 

 particular property of decomposing the bile salts, giving rise to a pre- 

 cipitation of cholesterin, and Dorr 95 experimentally produced small 

 concretions in the gall bladder of infected animals. Typhoid bacilli 

 have often been found in gall stones. Furthermore, obstruction of the 

 bile and stagnation due to inflammatory processes may be indirectly 

 responsible for stone formation. 



It is probable that typhoid carriers possess an especially high 

 resistance to second attacks, higher even than that of the ordinary 

 individual who recovers without developing the carrier state. Kuster 

 reports that of 800 chronic carriers observed in the military hospital at 

 Cologne during two and one-half years, not a single clinical disturbance 

 attributable to the typhoid bacillus could be determined. The occur- 

 rence of cystitis, pyelitis and renal stones in typhoid carriers is not par- 

 ticularly common. 



Occasionally, typhoid carriers may possess -agglutinins and other 

 antibodies in the blood higher than normal. Lentz examined a number 

 of chronic carriers and found positive Widals in 10 out of 11; however, 

 only in dilutions of 1 : 20. Gaethgens 96 found both agglutinins and 

 opsonins higher in chronic carriers than in normal people, but Schone 97 



94 Exner and Heyworski, Wien. klin. Woch., 1908, 7. 



95 Don', cited from Klistcr, loc. cit. 



96 Gaethgens, Deut. med. Woch., 1907, 1337. 



97 Schone, Munch, med. Woch., 1908, 1063. 



