Tracing Typhoid Carriers by means of Sewage.

The classical method of detecting and tracing typhoid carriers is by investi gation of probable cases followed by analysis of individual fecal or rectal swab specimens. These procedures are complicated, time consuming and, more important, they require extensive con tact with large numbers of people. A simplified, impersonal screening pro cedure for narrowing down the sus pected area in which the carrier will probably be found would, therefore, be desirable. Moore (1), in 1948, developed such a procedure based on the analysis of flowing sewage at various points in a sewer system. Although Moore's method has often been used successfully in locating carriers of enteric diseases in English communities, its use in the United States has been limited. It is the purpose of this paper to describe a field study in which Moore's method was used to locate a typhoid carrier and to make some general remarks on the utility of the procedure.