A total of 22 people fell ill with Staphylococcal food poisoning after an undisclosed military unit luncheon in July 2012, according to information made available in the latest Morbidity and Mortality Weekly Report from the U.S. Centers for Disease Control and Prevention.
The newly revealed outbreak serves as a reminder of the importance of properly cooling and heating food, as it likely resulted from holding cooked food at room temperature, allowing for easy growth of bacteria.
The incident started when 13 people sought medical care two to three hours after the lunch. Attendees had eaten a number of items, but epidemiological analysis soon implicated the outbreak vehicle as perlo, a southern dish featuring chicken, sausage and rice.
Investigators took stool samples from three of the patients, all of whom tested positive for Staphylococcus intoxication. Laboratory testing on samples of the four main dishes at the luncheon revealed Staphylococcal enterotoxin in the perlo dish, while none appeared in the other foods.
As it turns out, after heated preparation in a stock pot, the cooked perlo was left to sit in an unheated oven overnight for approximately eight hours. The next day, it was transferred to a slow cooker and reheated for approximately one hour.
Of the 22 patients, 19 experienced with nausea, 17 came down with diarrhea, 17 with abdominal pain, 15 with vomiting, 13 with headaches and four with fevered chills.
According to CDC, Staphylococcus intoxication begins with a rapid onset of nausea, along with violent vomiting, abdominal cramping and diarrhea. Onset usually occurs around three hours after ingestion, and the illness typically lasts 24-48 hours.
Staphylococcus bacteria reproduce between the temperatures of 43 to 118 degrees F (6 to 48 C). The bacteria produce enterotoxin at a range of 50 to 115 F (10 to 46 C).
Cooked food sitting within those temperatures has the potential to allow Staphylococcus bacteria in the environment to produce toxin within it. Food handlers carrying Staphylococcus aureus in the noses or on their hands are the main source of contamination in food.
The likely cause of the outbreak occurred when the food worker preparing the perlo handled cooked chicken with their bare hands. By allowing the dish to sit at room temperature for several hours, the food handlers provided ample time for the bacteria to produce harmful levels of toxin.
“Once toxins are produced, they are retained through subsequent food preparation and storage processes and digestive tract ingestion,” the report read. “Measures to prevent the proliferation of the S. aureus organism therefore are critical.”
Food handlers can prevent Staphylococcus illnesses through clean food preparation and immediately storing foods at temperatures below 41 degrees F (5 C).
“In this outbreak, as in many others, poor food handling practices and inadequate refrigeration of foods were identified as the main contributing factors,” the report concluded.© Food Safety News