[A waterborne outbreak of typhoid fever associated with a small drinking water supply system in Fuji city].

Fifteen cases of typhoid fever occurred in "HARADA" district Fuji City in Shizuoka Prefecture during the period of 1983 to 1985. Epidemiological and bacteriological investigations were carried out on the samples from a small water supply system, and drains of apartment houses in 1985. Water from a small river in the neighboring water supply system, and faecal specimens from people living in close proximity were investigated. The results obtained were as follows: 1) Salmonella typhi were isolated from 3/3 patients (1 pupil and 2 employees) in 1983, 3/5 patients (3 employees) in 1984, and from 4/7 patients (1 kindergartner, 1 pupil and 2 junior high school boys) in 1985. Phage type of these isolates were the same type "D1". 2) In the bacteriological survey on environment, S. typhi (phage type D1) were isolated from water of the water source of "HARADA" water supply in Fuji City with membrane filter methods, and from the sand source "HARADA" water supply with enrichment culture methods. Also, with an examination that tested 3,670 inhabitants, it was found that a carrier (phage type D1) was living near the "HARADA" water supply. 3) In the three selective media for the isolation of S. typhi, Bismuth sulfite agar (Difco) was the most sensitive, and detected 13 samples (61.9%) out of 21, from water source and sewage.