nfluenza (Also called H. influenzae) - Represents a group of bacteria that may cause different types of infections in infants and children. H. influenzae most commonly causes ear, eye, or sinus infections, and pneumonia.

Haemophilus is a genus of Gram-negative, pleomorphic, coccobacilli bacteria. While Haemophilus bacteria are typically small coccobacilli, they are categorized as pleomorphic bacteria because of the wide range of shapes they occasionally assume. The genus includes commensal organisms along with some significant pathogenic strains such as H. influenzae—a cause of septicemia and bacterial meningitis in young children—and H. ducreyi, the causative agent of chancroid.