Group A: one species with 40 antigenic types (S. pyogenes).

Group D: five species (S. faecalis, S. faecium, S. durans, S. avium, and S. bovis).

Group D: May produce a clinical syndrome similar to staphylococcal intoxication.

Group D: Diarrhea, abdominal cramps, nausea, vomiting, fever, chills, dizziness in 2-36 hours. Following ingestion of suspect food, the infectious dose is probably high (greater than 107 organisms).

Group D: Culturing of stool samples, blood, and suspect food.

Group D: Food sources include sausage, evaporated milk, cheese, meat croquettes, meat pie, pudding, raw milk, and pasteurized milk. Entrance into the food chain is due to underprocessing and/or poor and unsanitary food preparation.

Group D: Diarrheal illness is poorly characterized, but is acute and self-limiting.

Group A: Outbreaks of septic sore throat and scarlet fever were numerous before the advent of milk pasteurization. Salad bars have been suggested as possible sources of infection. Most current outbreaks have involved complex foods (i.e., salads) which were infected by a food handler with septic sore throat. One ill food handler may subsequently infect hundreds of individuals.

Group D: Outbreaks are not common and are usually the result of preparing, storing, or handling food in an unsanitary manner.

During December 1995-February 1996, four cases of a bacteremic illness (three accompanied by cellulitis and the fourth with infective endocarditis, meningitis, and probable septic arthritis) were identified among patients at a hospital in Ontario. Streptococcus iniae, a fish pathogen not previously reported as a cause of illness in humans (1-3), was isolated from all four patients.

In the period October 17, 1985-January 9, 1986, 44 episodes of pyoderma occurred among 32 workers in an Oregon meat-packing plant. Most of the 44 reports involved impetigo-like lesions on the hand, wrist, and forearm, but six episodes of cellulitis and two of lymphangitis were also reported. The same epidemic strain of Group-A, -B hemolytic Streptococcus (GAS) isolated from skin lesions was also isolated from meat in the plant.

Two large outbreaks of foodborne group A streptococcal pharyngitis have been reported to CDC during 1984. The Puerto Rico Department of Health was notified of the outbreak on August 8. Because of the high attack rate and the clustering of cases, the outbreak was presumed to be foodborne. Another outbreak occurred among participants from seven states at a meeting held at a Kansas City, Missouri, hotel from May 31, to June 1, 1984. Clustering of cases and a high attack rate suggested a foodborne source.

Between July 25 and September 9, 1983, 16 cases of invasive group C streptococcal infection were identified in northern New Mexico. The group C streptococcus was isolated from the blood of 15 patients and the pericardial fluid of one patient. The organism isolated from 14 of the patients has been identified as a group C B-hemolytic streptococcus--species Streptococcus zooepidemicus; the species of the remaining two isolates have not yet been determined. Initial questionnaires identified eating "queso blanco," a homemade white cheese, as the only risk factor associated with illness.