Two methods of typing group A hemolytic streptococci have been described: slide agglutination and anti-M precipitin tests. The first, developed by Griffith (1), is more extensively used. I t has the distinct advantages of requiring small amounts of serum and culture, and of a quick reaction time when all conditions are favorable. It has certain disadvantages: The granular growth of some strains of streptococci is so marked that much subculturing is necessary before they are suitable for testing, and many days or weeks may elapse before the final result is available. Cross reactions are not uncommon, and make it impossible to differentiate certain types unless specially prepared sera are used which have been absorbed with regard to the antigenic relationships among types. This is due, in part, to the presence in group A streptococci of two antigens related to type specificity, so called M and T, which in a given microorganism do not always correspond (2, 3). Antibodies for one or both of these antigens have been used for the identification of types by the agglutination method. It is no~v evident that several types contain common or closely related T antigens, but that members of each type elaborate a distinct type-specific M substance (4). So far, we have only once encountered the antigenic combination consisting of two types with a common M substance and distinct T antigens. Probably a thorough understanding of the usual antigenic make-up of each type will eventually result in more satisfactory slide agglutination tests.Anti-M precipitin typing is more precise in that a single antigen-antibody system is involved, and there is relatively little crossing among types when

Disease is the accomplice of war. To the uninitiated, at first glance, it seems that the chief wastage of man power in armies is produced by weapons of the enemy; to the initiated, on the other hand, it is well known that the wounds produced by bacteria are as fruitful a source of disability as those caused by bullets. One reason for this attitude on the part of the casual observer is that the injuries of battle are more spectacular than those of disease. They are more unusual, both in their mode of production, and in the manner in which they respond to treatment. The care of the wounded often yields striking results. The humanitarian instincts, aroused by the fact that the injuries were received as a direct result of sacrifice, properly lead to the building up of an intricate organization for the care of the wounded. The problems must be solved largely in the actual presence of war.

No abstract

While investigating the antistreptolysin content of patients' sera according to Todd's method (1-3), we found that the hemolytic titer of one given streptolysin might vary considerably within a short period. The purposes of this communication are: first, to show that although the hemolytic titer of such a streptolysin does vary, its power of combining with antistreptolysin is constant under certain conditions; and second, to discuss the effect of this phenomenon upon the standardization of streptolysins which are to be used in testing sera for antistreptolysins.Neill and Mallory (4) demonstrated that streptolysin may exist in at least two forms: (a) reduced and hemolytic, and (b) oxidized and non-hemolytic. They further showed that these two forms are easily reversible, one to the other, by oxidation and reduction. Such a reversibility would readily explain variations in hemolytic titer because the degree of hemolysis depends upon the amount of the reduced (hemolytic) form alone; such a reversibility, nevertheless, might not change the total streptolysin present in a given lot of hemolytic broth. It seemed to us that this hypothesis predicates a constant combining capacity of streptolysin with antistreptolysin even though the hemolytic strength might vary. In order to test it the following experiments were performed.Large amounts of streptolysins Nos. 32, 33, and 35 were made. Each batch was divided into several different samples and each sample was subjected to different conditions, in order to obtain different hemolytic titers. In these experiments, the amount of hemolytic broth required to hemolyze completely 0.5 cc. of 5 per cent red blood ceils in 1 hour was determined; this is known as 1 ~r.H.D. (minimal 277 on

At present there is relatively little information concerning the type-specific aspects of immunity to group A streptococcal infections in man. It has been demonstrated that an individual may suffer several different group A streptococcal infections within a single year. Although relatively few patients have been followed over long periods of time with adequate bacteriological studies, we do not know of a single instance in which it has been shown that the same patient suffered more than one nasopharyngeal infection with the same type of streptococcus. It is also now well known that the great majority of late purulent complications (1-5), and invariably the relapses and intercurrent sore throats