February, '09] JOURNAL OF ECONOMIC ENTOMOLOGY 41 



five of which the typhoid bacillus was isolated. She further found 

 that many discharges from typhoid patients were left exposed in 

 privies or yards, and concluded that flies might be an important ad- 

 junct in the dissemination of this infection. ]\Iore recently, Dr. 

 Daniel D. Jackson, investigating in 1907 the pollution of New York 

 harbor, found that by far the greater number of cases occurred A\-ithin 

 a few blocks of the water front, the outbreak being most severe in 

 the immediate vicinity of sewer outlets. He gives a series of charts 

 showing an almost exact coincidence between the abundance of house- 

 flies and the occurrence of typhoid fever when the dates are set back 

 two months to correspond to the time at which the disease was con- 

 tracted. The bacilli of typhoid fever were found by Ficker in the 

 dejecta of house-flies 23 days after feeding, while Hamer records the 

 presence of this bacillus in flies during a period of two weeks. Most 

 signiflcant of all, it should be noted that competent physicians in po- 

 sition to make extended observations upon this disease and the meth- 

 ods by which it may become disseminated, are most strongly of the 

 opinion that under certain conditions at least, the fly is a most impor- 

 tant factor. Epidemics spread by flies, according to Dr. Veeder, tend 

 to follow the directions of prevailing warm winds. He considers flies 

 the chief medium of conveyance in villages and camps where shallow, 

 open closets are used, thus affording the insects free access to in- 

 fected material, and where it is possible to eliminate water and milk 

 as the sources of infection. Drs. Sedgwick and Winslow,. writing in 

 1903, state that "the three great means for the transmission of ty- 

 phoid fever are fingers, food and flies, ' ' the authors holding the last to 

 be the most important. 



The possibilities of transmitting typhoid fever are appalling to 

 the layman when it is remembered that the germs of this disease 

 may be in the system several weeks before diagnosis is possible, 

 continue in numbers six to eight weeks after apparent recovery, and 

 in exceptional cases may be discharged from the system during a 

 period of several years. There are authentic records of a patient 

 distributing these germs for seventeen years and being the incipient 

 cause of thirteen cases during fourteen years of that period. Fur- 

 thermore. Dr. ]\I. A. Veeder of Lyons cites a case ■ where typhoid 

 fever was perpetuated from year to year in a locality, ascribing it to 

 a physician recommending the burial of all tj^phoid excreta and the 

 execution of this direction by a favorite nurse. It is well known 

 that soil infected by these germs may be the origin of new cases, and 

 Dr. Veeder significantly observes that the annual recurrence of ty- 

 phoid fever in the above mentioned locality ceased wdth the death 



