Haemophilus influenzae. Gram negative, non-motile, non-sporing rod of the genus Haemophilus in the Brucellacae family. Pfeiffer first found this bacillus in the sputum of patients with the Russian flu and, soon afterwards, also in the sputum of the victims of the Spanish flu. It was soon discovered, however, that the presence of the bacillus was a result of the disease, not its cause, which is a virus. It is found in the respiratory tract and causes acute respiratory infections, acute conjunctivitis, bacterial meningitis, and purulent meningitis.
- R. F. J. Pfeiffer:
Vorläufige Mittheilungen über den Erreger der Influenza.
Deutsche medicinische Wochenschrift, Berlin, 1892, 18: 28. Die Aetiologie der Influenza.
Zeitschrift für Hygiene und Infektionskrankheiten, 1893, 13: 357-386.