878 THE ALCALIGENES— DYSENTERY— TYPHOID GROUP 
have been in contact with the patient. The organism may occur in 
the fecal discharges of patients before chnical symptoms develop, 
in patients recently recovered from the disease, in carriers (which 
number about 2 per cent of all cases diagnosed), and probably in 
a relatively few individuals in whom the organism may gain a tem- 
porary foothold without producing symptoms. The bacilli may be 
transmitted to others by the hands of those who care for the patients, 
and the hands of carriers. Fecal matter containing typhoid bacilli 
may be transferred by flies, by water, through milk, and perhaps by 
vegetables which are eaten uncooked. The water in which typhoid 
patients have bathed is frequently grossly contaminated with the 
organisms. Rarely, wells and water supplies are contaminated by 
urinary typhoid carriers, in which event the colon bacillus, which is 
ordinarily relied upon for evidence of contamination, may be absent. 
A thorough disinfection of excreta including urine will prevent spread 
of the disease from known cases. 
THE PARATYPHOID GROUP. 
There is a group of closely related bacilli which exhibit cultural 
and pathogenic characters intermediate between those of the typhoid, 
dysentery and colon groups of bacteria respectively. These organ- 
isms are variously known as the hog cholera. Salmonella, Gartner, 
enteritidis, intermediate, paracolon or paratyphoid group. 
Smith and Salmon^ isolated the type organism of the group from 
the intestinal contents of swine infected with hog cholera. They 
named their organism the hog cholera bacillus.'- Three years later 
Gartner^ described an organism, B. enteritidis, recovered by him 
both from the spleen and blood of a fatal case of meat-poisoning, and 
from the suspected meat (beef) itself. Numerous epidemics of meat 
poisoning'' have been studied bacteriologically during the years fol- 
lowing Gartner's discovery, and very similar, if not identical, bacilli 
have been recovered from many of the patients. 
In 1893 Smith and Moore* made the important observation that 
organisms culturally indistinguishable from the hog cholera bacillus 
could be isolated not infrequently from the intestinal contents of 
normal cattle, swine, sheep, cats and dogs. The significance of this 
discovery from the view-point of meat poisoning was not understood 
at that time. 
> Ann. Rep. United States Bur. Animal Indus., 1885, vol. 2. 
2 A year earlier Klein (Virchow's Arch., 1884, 95, 468) obtained a bacillus from dis- 
eased swine which he regarded as the causative factor of hog cholera, but his organism 
produced spores, which at once distinguished it from the paratyphoid tji^e. Neither 
the Klein bacillus nor the Smith-Salmon bacillus causes hog cholera; a filterable virus is 
the probable infecting agent. 
' Correspondz.-Blatt des allgem. arztl. Vereins von Thiiringen, 1888, No. 9. 
■• Not to be confused with botulismus (see B. botulinus). 
* Additional investigations concerning swine diseases, Washington, D. C, 1893. 
