Haemophilus influenzae

Haemophilus influenzae is a gram-negative, coccobacillary, facultatively anaerobic pathogenic bacterium belonging to the Pasteurellaceae family. Haemophilus influenzae is a fastidious organism that can be isolated on chocolate agar as it contains essential nutirents required for the growth. Unencapsulated strains of Haemophilus influenzae are the most common cause of mucosal infections including otitis media, conjunctivitis, and bronchitis. The vaccine contains type B capsular polysaccharide and PRP (polyribosylribitol phosphate) conjugated to diphtheria toxoid and is given between 2 and 18 months of age. Treatment ususally includes amoxicillin +/− clavulanate for mucosal infections; ceftriaxone for meningitis; and rifampin prophylaxis for close contacts.