48 An Introduction to Medical Mycology 



inflammation varying in degree from fine, branny scaling in some cases 

 to phlegmonous localizations in others. 



(a) Etiology.— During the past few years, a widespread epidemic of 

 scalp ringworm affected children throughout the United States. At this 

 time ( 1948 ) there is some evidence that it is slowly resolving, but in many 

 communities the problem is still acute. The predominant micro-organism 

 is Microsporum audouini. Except under epidemic conditions, tinea of the 

 scalp is usually due to one of two Microspora, M. audouini and M. lanosum. 

 In New York under ordinary conditions the incidence of these micro- 



TABLE 13.— Cause of Tinea Capitis As Found in New York City before 



AND DURING THE EPIDEMIC 



organisms is almost equal; they are the cause in about 80 per cent of all 

 cases (Table 13). The remainder of the infections are caused by a scatter- 

 ing of micro-organisms (Table 13). In California and in most parts of the 

 Western and Southern states, M. lanosum is the predominant organism. 

 No definite statement, however, is possible without cultural studies. Leh- 

 man, in San Antonio, Texas, has observed that a greater percentage of 

 infections were due to M. audouini, whereas Smith, in El Paso, reported 

 that he rarely encountered this organism and that in most of his cases 

 ringworm of the scalp was caused by M. lanosum. In the Midwestern and 

 Eastern states, M. audouini probably is the most frequent cause of tinea 

 capitis. In Europe, M. lanosum is uncommon; in most cases, ringworm of 

 the scalp is caused by M. audouini. The condition is more often observed 

 in cities than in the country and is seen chiefly among the poor, particularly 

 when there is overcrowding. It affects more boys than girls, the ratio being 

 about 3:1. Crocker stated that in 600 cases the disease was 6 per cent more 

 prevalent in boys. Beeson noted that 85 per cent of his patients were boys. 

 In Pardo-Castello's series, there was only one girl to 31 boys. However, 



