Haemophilus influenzae

Background

Microbiology

• Species of Gram-negative bacillus within the genus Haemophilus
• Deficient heme biosynthetic pathway leading to X-factor-dependent growth on media
• May be encapsulated; non-encapsulated strains are referred to as "nontypeable"
• The group includes Haemophilus influenzae, Haemophilus aegyptius, and Haemophilus haemolyticus

Test	Biotype
	I	II	III	IV	V	VI	VII	VIII
Indole	+	+	–	–	+	–	+	+
Urease	+	+	+	+	–	–	–	–
ODC	+	–	–	+	+	+	–	–