1. Of the 65 people attending a retirement picnic, 37 patients ranging in age from 6 to 78 years acquired symptoms of classical community-acquired food poisoning. Gastroenteritis can be caused by bacterial enterotoxins or exotoxins.  In this case, the causative agent was determined to be Salmonella species, serotype epidermitidis. which produces enterotoxins.

2.  Symptoms consisted mainly of acute abdominal cramps, diarrhea and vomiting. Only three elderly patients were admitted to the hospital for overnight observation and treatment for mild dehydration.

3. The diagnosis is made by isolating the causative agent from the patient's stool. New laboratory techniques make this possible within 24 hours.  A fecal white blood count determines if the organism is invasive.  Serum electrolytes and hematocrit help determine the degree of dehydration.

4. Treatment of Salmonella food poisoning consists of managing the main symptoms (vomiting and diarrhea), and when indicated, replacement of fluids and electrolytes. Hospitalization is only required when patients exhibit severe symptoms, or have an underlying condition (e.g. poor renal function or gastrointestinal disease) which could worsen the illness. Antibiotics are not indicated except in severe cases when the bacteria spreads to the bloodstream or other body sites.

5. Even though public health agency personnel conducted through examination of the company which provided the picnic foods, the source of the Salmonella could not be confirmed by standard examination procedures.  Suspected foods were sliced sandwich meats (turkey and roast beef) and the potato salad.  Salmonella is prevalent in nature, found in meats, dairy products, especially eggs (poultry carry Salmonella in their intestinal tracts), and reptiles such as lizards and turtles.  

"Every year, approximately 40,000 cases of salmonellosis are reported in the United States. Because many milder cases are not diagnosed or reported, the actual number of infections may be twenty or more times greater. Salmonellosis is more common in the summer than winter.

Children are the most likely to get Salmonellosis. Young children, the elderly, and the immunocompromised are the most likely to have severe infections. It is estimated that approximately 1,000 persons die each year with acute salmonellosis. "  Taken from the CDC

Public health agencies, county state and federal all have distinct guidelines for consumers and food vendors. State agencies require food handlers permits and facilities preparing and serving food are regularly inspected for compliance to established guidelines. In spite of this, there are tens of thousands of cases of bacterial food poisoning each year, many unreported.

6. Prevention of food poisoning in general requires careful attention during food processing and preparation.  Un-refrigerated foods such as salads prepared with dairy products such as mayonnaise should be avoided. Meats, especially cold meats that have been allowed to sit in warms environments are also a common source. Unwashed vegetables can also be a source of Salmonella.

7. Public health personnel have the responsibility to investigate any public outbreak of disease.  In this case they investigated the catering company which they could shut down if they found they were at fault.  They also must follow all of the cases involved and inform others who may have been at the picnic and may be at risk. 

The emergency and family physicians treated the dehydration, ordered necessary laboratory tests, and prescribed antibiotics to those patients with severe infections, hospitalizing patients when necessary.

Nursing personnel monitored severe cases, administered lactated ringers to alleviate dehydration and other medications.

Medical laboratory personnel cultured the patients' stool samples, identified the Salmonella, and tested for appropriate antibiotics.