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Streptococcus
spp.
Characteristics
into Groups A, B, C, D, F, and G. Groups A define Streptococcocal
bacteria and D can be transmitted to humans via food.
Group
A: one species with 40 antigenic types ( S. pyogenes ).
Group
A can cause septic sore throat (strep throat) and scarlet fever
as well as other pyogenic and septicemic infections. Sore and red
throat, pain on swallowing, tonsillitis, high fever, headache, nausea,
vomiting, malaise, rhinorrhea; occasionally a rash occurs, onset
1-3 days .Group A is diagnosed by culturing of nasal and throat
swabs, pus, sputum, blood, suspect food, environmental samples.
Food
sources include milk, ice cream, eggs, steamed lobster, ground ham,
potato salad, egg salad, custard, rice pudding, and shrimp salad
.
In
infections food was allowed to stand at room temperature for several
hours between preparation and consumption. Food contamination is
the result of poor hygiene, ill food handlers, or the use of unpasteurized
milk.
Outbreaks
of strep throat and scarlet fever were common before milk pasteurisation.
Salad bars have also been sources of infection. Most current outbreaks
involve complex foods (i.e., salads) that are infected by a food
handler with strep throat, which may subsequently infect hundreds
of individuals.
Group
D: five species ( S. faecalis , S. faecium , S.
durans , S. avium , and S. bovis ).
May produce a clinical syndrome similar to staphylococcal intoxication
Following ingestion of infected food cause diarrhea, abdominal cramps,
nausea, vomiting, fever, chills, and dizziness in 2-36 hours. Group
D is diagnosed by culturing of stool samples, blood, and suspect
food
Infected
foods include sausage, evaporated milk, cheese, meat croquettes,
meat pie, pudding, raw milk, and pasteurised milk.
Food
contamination is due to under processing and/or poor and unsanitary
food preparation. Outbreaks are usually
the result of preparing, storing, or handling food in an unsanitary
manner.
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