Bacillus Influenzae is a minute, non-motile, non-liquefying, aerobic bacillus found in the discharge from the nose and bronchi of those affected by influenza. Is also sometimes found in the blood. Is very small, about 0.2 X 0.5 µ, are usually single, but may occur in chains of three or four.

Stains

Ordinary methods, but not by Gram's.

Culture

Grows poorly on artificial media. Will not grow at all on ordinary gelatin or agar-agar. Develops best upon media containing blood. Colonies appear as minute colorless bodies, looking like dewdrops. They do not coalesce. Is easily destroyed; 6o° C. for five minutes will kill it. Will not grow below 280 C.

Fig. 96. - Agglutination of the Typhoid Bacillus by a Specific Serum.