Semi-Centennial Volume. 31 



to man. Ehrlich worked hard to conquer it and did produce a drug, 

 atoxyl, which gave some hope of success. Some of the trypanosomes 

 became immune to the drug, however, and so the purpose of the treat- 

 ment is thwarted. The most hope at present seems to lie in preventive 

 measures such as isolation of the sick. The outlook on the whole seems 

 discouraging. We are all familiar with recent developments in the 

 bubonic plague. It has come too close for comfort, being fairly well 

 established in California. We know too of the rat-proofing of New 

 Orleans, and of the amount of work and heavy expense incident to such 

 a heroic measure. It is well to bestir ourselves. The "black death" 

 claimed twenty-five million people in 1348-1349. From 1898 to 1907 it 

 caused about six million deaths in British India. We all probably re- 

 member the epidemic of the pneumonic type of this disease in Man- 

 churia in 1910 and 1911. The mortality there was over 90 per cent. The 

 transmission of the ordinary type by the flea, aided by rats, was demon- 

 strated early in the century, 1906 and on. Again one of our number. 

 Professor Barber, is quoted as an authority in a report made while he 

 was in the Philippines (Tropical Medicine, 1913, VIII, 241). Through 

 preventive measures such as the destruction of rodents, etc., and the use 

 of Haffkine's prophylactic, there is a possibility of control. Haffkine's 

 treatment is estimated to reduce the chances of infection four-fifths and 

 increase the chances of recovery two and one-half times. 



Again we are probably very familiar with tuberculosis, the great 

 white plague, its occurrence, effects, treatment, etc. We may not know 

 that the deaths from it in Massachusetts declined from 500 per 100,000 

 in 1855 to about 210 in 1906. The tubercle germ was discovered in 1882 

 and much work has been done with it since, especially by Robert Koch. 

 The germ has been demonstrated in nearly every organ of the body. 

 It is fairly certain that most people are, or have at some time been, 

 infected. From this we see that methods of attacking it should be 

 largely the building up of the resisting powers of the body and thus 

 prevent its encroachment upon the unaffected tissue. Early diagnosis 

 also helps. Sanatoria, where the sick may receive proper treatment 

 white uninfected dependents are cared for at home, are being erected by 

 some states and other institutions. The state can well afford this if 

 any appreciable amelioration results. It is estimated that tuberculosis 

 costs the United States from 150 million to 200 million dollars annually 

 in money. In 1900 it caused about one-ninth of all deaths. Infection 

 by man from the bovine type is supposed to be higher in children and 

 nearly negligible in adults. 



Leprosy has, like tuberculosis, been long known among men. It was 

 quite prevalent in Bible times. The present situation is quite hopeful. 

 Treatment is limited largely to isolation and betterment of living condi- 

 tions about as in tuberculosis. Cures are probably rare. By mild rules 

 of segregation Norway has reduced the number of cases from 2,870 in 

 1856 to 577 in 1900. Like many other diseases it can probably be 

 readily stamped out through the application of known principles of 

 procedure. 



The great mortality among infants during the hotter months has 

 long been noted. Much has been done to lessen this through the ob- 



