UTILIZATION OF ANTIBIOTICS 



115 



It is the last group with which we are con- 

 cerned here. 



It has been said that much greater 

 progress has been made in the treatment of 

 infectious diseases during the last 15 or 20 

 years than in all previous medical history. 

 The first real progress in combatting infec- 

 tious diseases was made during the latter 

 part of the last century with the discovery of 

 immune sera and antitoxins. This was fol- 

 lowed by the work of Paul Ehrlich and others 

 on the great potentialities of the arsenicals 

 as chemotherapeutic agents, resulting in the 

 discovery of salvarsan in 1910. A quarter of 

 a century later came the sulfonamides, 

 broader in scope and of much wider appHca- 

 tion. They were soon followed by discovery 

 of the antibiotics, of which penicillin and 

 streptomycin were the first two most strik- 

 ing examples. 



The mere listing of the various uses of 

 antibiotics is sufficient to emphasize their 

 broad application. 



I. Treatment of infectious diseases. 

 A. Infectious diseases of man. 



1. Diseases caused by gram-posi- 

 tive bacteria; penicillin, chlor- 

 amphenicol, tetracyclines, eryth- 

 romycin, and \'ari()us others are 

 used. 



2. Diseases caused by gram-nega- 

 tive bacteria (gastrointestinal in- 

 fections, tularemia, plague, chol- 

 era, and numerous others); 

 streptomycin, neomycin, chlor- 

 amphenicol, tetracyclines, and 

 certain others are effective. 



3. Various forms of tuberculosis; 

 streptomycin and certain other 

 antibiotics have found particular 

 application. 



4. Diseases caused by rickettsiae 

 and the psittacosis-lymphogran- 

 uloma group of organisms; the 

 tetracyclines, chloramphenicol, 

 and erythromycin are used. 



5. Diseases that can be treated ef- 

 fectively by combinations of 

 antibiotics with synthetic com- 

 pounds. 



B. Numerous animal diseases that af- 

 flict poultry, swine, dogs, cats, and 

 other domesticated animals. 



C. Plant diseases caused by bacteria 

 and certain fungi. 



1. Fireblights and other bacterial 

 diseases of trees. 



2. Bacterial diseases of vegetables, 

 such as string beans and peppers. 



3. Bacterial diseases of flowers, such 

 as carnations. 



4. Diseases caused by fungi, such as 

 the blue mold of tobacco. 



II. Treatment of diseases, noninfectious in 

 nature, notably neoplasms. 

 III. Preservation of valual)le biological 

 products. 



A. Virus preparations. 



1. Poliovirus. 



2. Poultry vaccines 



B. Human and animal semen. 



C. Foodstuffs, notably fish and poul- 

 try. 



I\\ Animal feeding. 



More than 30 antibiotics are now avail- 

 able for the treatment of various infectious 

 diseases caused by bacteria, fungi, protozoa 

 (amoebae, trichomonads, etc.), rickettsiae, 

 the psittacosis-lymphogranuloma group, and 

 certain worms. Some are more effective than 

 others. Some are best used orally, others by 

 injection, still others by surface application. 

 The development of resistance against one 

 necessitates the use of others, l^ndesirable 

 reactions caused by a particular antibiotic 

 through one method of administration, as in 

 the case of neomycin used parenterally, sug- 

 gest other methods of administration, as oral 

 or topical for neomycin. 



Animal experiments cannot always be 

 considered as true representations of the 

 chemotherapeutic potentialities of a given 



