564 The Philippine Journal of Science 



OF FINDINGS 



Graham-Smith, :: tabulating the findings of several authors, 

 found that 2.6 per cent of persons who have not come in contact 

 with diphtheria cases harbor nonvirulent diphtheria bacilli, and 

 0.18 per cent harbor virulent bacilli. 



The number of cases that we have examined is fairly repre- 

 sentative of the entire population of Manila, although our find- 

 ings, 2.08 per cent of healthy individuals being carriers, are 

 necessarily low on account of our having examined only one 

 specimen from practically all the cases. These findings are 

 sufficient to establish the fact that there is a certain per- 

 centage of people in the population in Manila that harbor diph- 

 theria bacilli; and that the diphtheria bacilli found in normal 

 throats are usually nonvirulent, a small proportion being viru- 

 lent; that is, four, or 11 per cent, of the thirty-five isolated, or 

 about 0.22 per cent of the total number of people examined. 

 This is in striking contrast with the findings in cultures of 

 diphtheria bacilli isolated from clinical cases in San Lazaro Hos- 

 pital, practically all of which have been found to be virulent. 

 The nonvirulent bacilli isolated differ in no other respect, 

 morphologically and culturally, from those isolated from the 

 throats of patients suffering from the disease. 



The work in the Santa Clara Public School was started on 

 account of a case of diphtheria that occurred in one of the pupils. 

 Another pupil (M.M.), in an entirely different room from the 

 one that was first taken sick, was found to be a carrier of 

 virulent bacilli and later developed a mild clinical diphtheria. 

 All the carriers from the school were isolated at the San Lazaro 

 Hospital, at different periods, and given treatment until the 

 diphtheria bacilli disappeared. The work connected with the 

 taking of specimens and the detection and isolation of individual 

 carriers was done within a period of about forty days. No 

 other cases of diphtheria developed in the school or among 

 people with whom the two cases of diphtheria associated in their 

 homes, although a sufficient period of time had elapsed, before 

 the detection and isolation of the carriers, for the possible spread 

 of the disease. 



In the Government Orphanage at San Pedro Macati no case 

 of clinical diphtheria has developed since its establishment in 

 1917, although carriers were found in the institution at the first 



, G. S., The Bacteriology of Diph- 



