INFECTION AND IMMUNITY. 41 



A similar hypersensitiveness has been observed in 

 some human beings to the horse serum in diphtheria 

 antitoxin, and the symptoms of serum sickness have 

 been attributed to it (see Diphtheria). The reactions 

 following the use of tuberculin and mallein are also 

 believed to be due to anaphylaxis. 



