A broccoli salad that had been served at a school lunch was blamed for causing an outbreak of Salmonellosis that involved more than 1,500 students and teachers at nine schools in Iwamizawa City, Hokkaido Prefecture, Japan. The identical strain of Salmonella was isolated from ill persons and from the broccoli salad. The salad was made at the city's joint school meal cooking center and served to the involved schools.