One hundred and sixty patients with symptoms suggestive of pharyngitis were prospectively studied. The responsible agent in 24% of the cases was streptococcus B haemolyticus group A (EGA) with a clear predominance of female (64%) over male (36%) patients. The greatest number of infections by S. Pyogenes was observed in the age group between 5 and 9 years. No positive cases were found in children less than 3 years old. Utilizing the quick latex agglutination test and comparing the results to those obtained with conventional cultures, a diagnostic fiability of 91% was reached, with 94% specificity, 82% sensibility, 82% PPV, and 94% NPV. These results together with the simplicity and convenience of the technique confirm the usefulness of this diagnostic method. No clinical symptom can be significantly related to streptococcus B haemolyticus pharyngitis. The diagnosis based on the clinical picture has turned out inefficient.