DISTRIBUTION OF BACILLI 423 



very grave. Regarding the presence of influenza bacilli in the 

 other pulmonary complications following influenza, much in- 

 formation is still required. Occasionally in the foci of sup- 

 purative softening in the lung the influenza bacilli have been 

 found in a practically pure condition. In cases of empyema the 

 organisms present would appear to be chiefly streptococci and 

 pneumococci; whilst in the gangrenous conditions, which 

 sometimes occur, a great variety of organisms has been found. 



Pfeiffer's observations on a large series of cases convinced 

 him that the organism was very rarely present in the blood 

 that in fact its occurrence there must be looked upon as 

 exceptional. The conclusions of other observers have, on the 

 whole, confirmed this statement, and it is probable that the 

 chief symptoms in the disease are due to toxins absorbed from 

 the respiratory tract (vide infra). The bacillus may be present 

 in some of the lesions complicating influenza. Pfeiffer found 

 it in inflammation of the middle ear, but in a case of meningitis 

 following influenza Fraenkel's diplococcus was present. In a 

 few cases of meningitis, however, the influenza bacillus has been 

 found, sometimes alone, sometimes along with pyogenic cocci 

 (Pfuhl and Walter, Cornil and Durante) ; Pfuhl considers that 

 in these the path of infection is usually a direct one through 

 the roof of the nasal cavity. This observer also found post 

 mortem, in a rapidly fatal case with profound general symptoms, 

 influenza bacilli in various organs, both within and outside of 

 the vessels. In a few cases also the bacilli have been found in 

 the brain and its membranes with little tissue change in the 

 parts around. 



Extensive observations on the bacteriology of the respiratory 

 system show that influenza-like bacilli may be present in a great 

 variety of conditions ; we have, in fact, once more to do with a 

 group of organisms with closely allied characters, of which 

 Pfeiffer's influenza bacillus was the first recognised example. 

 These "pseudo-influenza" bacilli have been obtained from the 

 fauces, bronchi, and lungs in inflammatory conditions, and also in 

 various specific fevers. To this group belongs the bacillus which 

 has been cultivated from cases of whooping-cough by Spengler, 

 Jochmann, Davis, and others, and which is present in considerable 

 numbers in a large proportion of cases of this disease. Wollstein 

 has obtained a marked agglutinative reaction on this organism 

 by the serum of whooping-cough patients, all the sera examined 

 giving a positive reaction in a dilution of at least 1 : 100 on all 

 the strains of the organism isolated ; on the other hand, clumping 

 was never obtained with a normal serum in a greater dilution 



