Laboratory diagnosis of Haemophilus influenzae

a. General considerations

Find more information about Infectious disease associated with Haemophilus spp and specimen for culture

b.   Culture and identification for Haemophilus spp

Direct Examination


Flow chart Haemophilus influenzae identification

Colony morphology on Chocolate Agar

 Note:    Growth is enhanced on chocolate agar and  satellitism  around Staphylococcus aureus is seen on blood agar.

Biochemical reactions for differentiation.

            Confirmatory tests for X and V factor requirements.

X and V Factor: Growth is seen around XV Factor only.

Note that if only X and V factor discs (without XV) are applied, place them at least 2 cm apart and H. influenzae will grow between the two discs.

Serological identification (serotyping) of Haemophilus influenzae

Slide agglutination test.

Anti-microbial sensitivity testing of H. influenzae in Chocolate Agar



 Antimicrobial susceptibility testing.