560 INFECTION AND IMMUNITY. 



this is indicated by the distribution of the 111 

 cases observed by Councilman. Mallory and 

 Wright in Boston, the city being somewhat dif- 

 fusely infected with very little tendency of the dis- 

 ease to occur in groups of individuals or in several 

 members of a family. 



The desirability of avoiding contact with the 

 infected is evident; special prophylactic meas- 

 ures are not known. In the presence of an epi- 

 demic the treatment of rhinitis with local antisep- 

 tics would suggest itself. 



Children and young people are particularly sus- 



bilityand ,.,, 1.1 -, j j- i_- 



immunity, ceptible to both epidemic and sporadic infections 

 with the meningococcus. Exposure incident to the 

 cold and variable weather of the winter and spring, 

 in which seasons the disease prevails, may be in- 

 fluential in lowering resistance. Second attacks 

 are rare, Councilman, Mallory and Wright col- 

 lecting only five such examples from the literature. 

 Lipierre immunized animals with cultures and 

 with a toxin, the latter being a glycerin extract of 

 old cultures. Their resistance to infection was 

 said to be increased, and the serum of highly im- 

 munized animals was antitoxic, preventive and 

 curative for other animals. Corroborative work 

 is lacking. According to Davis, the serum in 

 cases of epidemic meningitis shows an increased 

 bactericidal power for the coccus on the thirteenth 

 day of the disease; the agglutinins which develop 

 probably persist for some time, but are little above 

 Normal human serum is distinctly bactericidal 

 toward the meningococcus. This property is 

 increased in sera of meningitis cases, and is dimin- 

 ished,, but not entirely destroyed, by heating to 60 

 C. for thirty minutes. Cerebrospinal fluid acts in 

 much the same way as heated serum. Normal 



