MENINGOCOCCUS 171 



Agglutinins. An agglutination reaction towards the specific 

 strain of meningococci causing the disease is often given if death 

 does not occur within the first few days. A positive reaction may 

 appear by the fourth day in a dilution of 1 to 50 ; at a later stage 

 it may even occur in as great a dilution as 1 to 400. A certain 

 number of strains, however, do not give the reaction, and for this 

 reason the test is unreliable and practically never used for diagnosis. 



An antiserum has been prepared by injecting horses with a 

 mixture of several strains of meningococci. A serum prepared 

 by Flexner and Jobling has been extensively used both in Amer- 

 ica and Europe and has given very satisfactory results; the use 

 of such an antimeningococcic serum has reduced the mortality 

 from 70 to 30 per cent and has greatly diminished the tendency 

 to chronic lesions in those who survive. 



To administer the antiserum a lumbar puncture is made in 

 about the third or fourth lumbar space, the cerebrospinal fluid 

 is allowed to flow until only about three or four drops come per 

 minute, and then the serum, which has been previously warmed 

 to body temperature, is allowed to flow in by gravity. The 

 average dose for a child is from 2 to 20 c.c. and for an adult from 

 20 to 40 c.c. More depends on the amount of fluid withdrawn 

 than the age of the patient. In severe cases the serum is injected 

 every twelve hours until there is an improvement; in milder 

 cases it is repeated each day for the first four days. Usually 

 from four to six injections are necessary although as many as 

 fifteen have been employed. 



Vaccines. As a prophylactic measure three injections at 

 weekly intervals of 250 millions, 500 millions, and 1 billion re- 

 spectively have been advocated. In cases where lumbar puncture 

 and serum treatment has had little effect an autogenous vaccine 

 is sometimes employed therapeutically. 



THE GONOCOCCUS 



Gonorrhea is one of the most widely disseminated of all 

 the infectious diseases. When it was first recognized is not 



