[A food-borne outbreak of group A streptococcal pharyngitis].

In August 1988, following a luncheon, an explosive epidemic of pharyngitis due to group A streptococci (M type 11, T type 3/13/B3264 and opacity factor positive) occurred among the staff of an institution in Ankara. Epidemiological investigation indicated that the outbreak was food-borne. A salad prepared by bean with boiled egg was incriminated as the vehicle of transmission. Group A streptococci were isolated from the throats of 37 (63.8 percent) of 58 persons with pharyngitis. High levels of antistreptolysin O titers were observed in serum samples from 39 (81.2 percent) of 48 persons with pharyngitis. Secondary transmission had accounted for only 3.8% of cases.