Salmonella in Commercially Produced Dried Dog Food: Possible Relationship to a Human Infection Caused by Salmonella enteritidis Serotype Havana

Abstract

Identification of Salmonella enteritidis serotype Havana, isolated from a 2'1>-month old female, engendered efforts to ttace the source of infection. The inquiry led to examination of commercially prepared dehydrated dog foods. Twenty-five samples, representing four different manufacturers plus two retail store brands, were examined. Each of 11 samples, produced by one manufacturer, contained one or more Salmonella serotypes. Eight of them contained S. enteritidis serotype Havana. Isolates of serotype Havana from the index case and her mother had antibiotic susceptibility patterns essentially identical to those of nine of 10 serotype Havana isolates recovered from one sample of dog food. The possibility that the human isolates were related to the dog food isolates could not be eliminated. Salmonella enteritidis serotype havana had not been encountered by the Milwaukee Health Department laboratory before December, 197 5. Therefore, recovery of this serotype from a stool specimen of an infant girl, at a Milwaukee hospital, triggered a series of events which led to presentation of this report. The child, approximately 2% months old, had developed a gastrointestinal illness December 6, 1975 and was admitted to a hospital on December 13, 1975. She recovered sufficiently to be returned to her home 2 weeks later. Follow-up cultures, prepared from the child's stooi specimens January 13, 1976 and March 8, 1976, were positive for S. enteritidis serotype Havana. Upon interviewing the child's mother on December 29, 1975, it was learned that a canine household pet had become ill November 28, 1975. The dog had refused food for 6 days and was observed to be suffering from "gagging". He was treated at a veterinary clinic for "digestive disruption", a stool specimen was not cultured at that time. However, a specimen collected from the dog January 13, 1976 was found to be positive for S. enteritidis serotype Newington. The child's mother, although asymptomatic, was found to have a stool culture positive for S. enteritidis serotype Havan on February 4, 1976; ssecond specimen was negative one month later. A 3-year-old sibling, and the chnild's father, each had stool cultures negative for