PERTUSSIS 417 



often complicate the influenzal attack. The organism also 

 occurs in bronchitis, broncho-pneumonia, and whooping- 

 cough. 



Although the typical influenza may be due to the B. influenzce, 

 many febrile conditions attended with pulmonary catarrh and 

 frequently termed " influenza " are not due to this organism. In 

 an epidemic simulating influenza occurring in Essex in 1905, the 

 examination was negative as regards streptococci, B. diphtherice 

 and B. influenzce, but the M. catarrhalis was present in number in 

 most cases (twenty-two out of twenty-four). This organism was 

 originally isolated by Seifert in a small epidemic of infectious 

 bronchitis, afterwards by Pfeiffer in cases of broncho-pneumonia in 

 young children (see p. 248). Two other Gram-negative cocci were 

 also isolated from three other cases (see Table, p. 248). 



Clinical Examination 



In cases of influenza, accompanied with bronchitis or pneumonia, 

 the influenza bacillus may be met with in large numbers in the 

 sputum, and their presence may aid in confirming the diagnosis. 

 Film preparations may be stained with carbol-methylene blue. 



Whooping-cough (Pertussis) l 



An influenza-like bacillus has been isolated by Koplik, Czaplewski 

 and Hensel, Davis and others in this disease, but the researches of 

 Bordet and Gengou have shown that it is distinct from the influenza 

 bacillus. 



The B. pertussis is a minute baciUus, very like the B. influenzce, 

 non-motile, non-sporing, and Gram-negative. It is scanty in the 

 bulk of the expectoration, but is abundant in the viscid exudate, 

 rich in leucocytes, coming from the depth of the bronchi, and voided 

 at the end of a paroxysm of coughing. 



It is best isolated on a medium consisting of defibrinated blood 

 (human or rabbit), thoroughly mixed with an equal volume of 3 per 

 cent, agar containing a little extract of potato made with 4 per 

 cent, aqueous glycerin. It forms on this a fairly thick whitish 

 streak, the subjacent blood being hsemolysed. It may also be 



1 See Bordet, Brit. Med. Journ., 1909, vol. ii, p. 1062. 



2? 



