THE SERUM TREATMENT OF INFLUENZAL MENINGITIS 803 



the nose cannot be excluded, and should be considered a possibility. 

 However, all or nearly all cases of spontaneous influenzal meningitis in 

 human beings are the result of influenzal bacteremia, since the bacilli 

 have been cultivated in large numbers from the heart's blood before and 

 after death. The same is true of experimental influenzal meningitis in 

 the monkey. 



According to Flexner, 1 the cerebrospinal fluid removed by lumbar 

 puncture from human patients is always turbid, and deposits a yellowish 

 or whitish sediment on standing. "As the disease advances, the fluid 

 becomes more heavily charged with pus-cells, until toward the end, and 

 as late as the seventh day of illness, the puncture may yield merely a 

 viscid mass of purulent matter. The number of influenza bacilli pre- 

 sent in the fluid is usually large, and the bacilli lie chiefly extracellular, 

 among the pus-cells, although a variable but small number is usually 

 found ingested by the leukocytes. In morphology the bacilli vary 

 somewhat, and in this respect the observer may readily be deceived as 

 to the nature of the bacteria present. While some of the fluids contain 

 the typical, minute rods, others show quite irregular and knobbed or 

 even filamentous bacteria that have little resemblance to the influenza 

 bacillus as seen in recent cultivations. These bizarre or involution 

 forms, however, are met in old and exhausted cultures; and when they 

 are recultivated on a suitable hemoglobin medium, they yield the typical 

 minute rods." 



The cerebrospinal fluid removed from monkeys inoculated by sub- 

 dural injection with virulent cultures of the influenzal bacillus resembles 

 in all essential particulars the fluid removed from patients with spon- 

 taneous infections. 



The bacteriologic diagnosis can usually be made by microscopic 

 examination of stained smears of the fluid, but whenever possible, the 

 diagnosis should be confirmed by cultural methods. 



Anti-influenza Serum. After having satisfactorily demonstrated 

 experimental influenza meningitis in the monkey, Flexner and Wollstein 

 prepared an immune serum and showed that the experimental infection 

 could be controlled and cured by injecting the serum directly into the 

 seat of disease by intraspinal inoculation. The immune serum was 

 prepared by the ordinary methods, first a goat and then a horse being 

 injected with non- virulent and finally with virulent bacilli, covering a 

 period of many months, until their serums showed the presence of 

 agglutinins and bacteriotropins. The serum lacked bacteriolytic prop- 

 1 Jour. Amer. Med. Assoc., 1913, Ixi, 1872. 



