The Rôle of Staphylococci in Food Poisoning.

Abstract

In food poisoning of the gastrointestinal type attention has been previously focused chiefly on the Salmonella (paratyphoid-enteritidis) group of bacilli. Some European observers have been unwilling to attribute etiological significance to any other organisms. During the past few years, however, material from a number of well defined food poisoning outbreaks, apparently of bacterial origin, has been subjected to thorough bacterial examination in our laboratories without being found to contain any paratyphoid bacilli. I have consequently become convinced that in a considerable number of cases some other bacterial factor is involved. A recent outbreak in Chicago in which a yellow staphylococcus was found by Dack and other workers 1 in this laboratory to be the probable causal agent has led me to carry out some observations on other staphylococcus strains.

With the aid of human volunteers the sterile filtrates of 6 staphylococci have been tested. From 5 to 10 cc. of sterile broth filtrates of these organisms taken by mouth has caused in a few hours the train of food poisoning symptoms commonly met with: dizziness, loss of appetite, nausea, vomiting and diarrhea. These staphylococci are of diverse origin and are not of uniform cultural character. Three of these were isolated from normal human throats, one from a case of septicemia in man and 2 from food implicated in “food poisoning” outbreaks. With the amounts of filtrate used not all volunteers were affected, but out of 34 taking approximately the same quantity 26 became definitely ill with characteristic symptoms. Eleven control subjects taking the same food at the same time without addition of filtrates remained well, but one reported the occurrence of food poisoning symptoms. Since this individual had been made quite ill with filtrates the previous week, the second attack may have been due to suggestion or to association with those who were ill.