During the course of epidemiologic investigations of typhoid fever the importance of the variability of clinical manifestations, the frequent failure of physicians to establish a diagnosis satisfactory to themselves, and the large percentage of cases in which positive agglutination reactions with the Bacillus typhosus were absent, particularly in water-borne epidemics, led to the observations herewith presented. It is the purpose of this paper to offer as a contribution the facts developed by serologic studies in certain epidemics to which I was assigned in charge under the direction of Dr. Samuel G. Dixon, Pennsylvania State Commissioner of Health.
By means of careful observations of the biochemistry and the agglutination properties of micro-organisms of the typho-colon type, it has been found that certain forms have characteristics which group them together; further, that their pathogenicity bears a somewhat definite relation to the grouping. For the purpose of study and
HUNT CJ. PARATYPHOID FEVER: A SEROLOGIC STUDY IN RELATION TO THE EPIDEMIOLOGY. Arch Intern Med (Chic). 1913;XII(1):64-80. doi:10.1001/archinte.1913.00070010067006