The occurrence of scarlet fever without a rash during epidemic.

Abstract

During the winter of 1924-25 an epidemic of scarlet fever and acute streptococcus pharyngitis occurred among the nurses at Presbyterian Hospital, New York City. Early in the epidemic the entire nursing staff was tested for susceptibility to scarlet fever by means of intracutaneous toxin injections. Following this series of skin tests cultures were obtained from all throats showing an angina. Practically all of the cases of pharyngitis and tonsilitis showed hemolytic streptococci. The strains of hemolytic streptococci recovered from these cases were tested for agglutination with scarlatinal immune sera and with sera prepared with two of the throat strains proven not to be scarlatinal strains. Filtrates were prepared from cultures of all these strains and tested for the presence of toxin by means of cutaneous reactions in Dick positive individuals. The presence of toxin was determined by heat lability (100 degrees C. for 2 hours), and by neutralization with scarlatinal antitoxic sera. Twenty-three strains of hemolytic streptococci were studied. Six strains, which were obtained from cases of clinical scarlet fever, produced a heat labile toxin which was neutralized by anti-scarlatinal sera. Five of the strains were agglutinated by two scarlatinal immune sera, and the sixth, although it did not agglutinate, absorbed the agglutinin from these sera for other scarlatinal strains. This strain was apparently physically incapable of agglutination, yet was similar antigenically to the other scarlatinal strains. These strains (six) include all the strains from clinical scarlet fever.