Bacteria Genomes - HAEMOPHILUS INFLUENZAE

Haemophilus influenzae is a small, non-motile Gram-negative bacterium in the family Pasteurellaceae.

Naturally-acquired disease caused by Haemophilus influenzae seems to occur in humans only. It was first isolated by Pfeiffer during the influenza pandemic of 1890. It was mistakenly thought to be the cause of the disease influenza, and it was named accordingly.

Haemophilus influenzae is highly adapted to its human host. It is present in the nasopharynx of approximately 75 percent of healthy children and adults. It is rarely encountered in the oral cavity and it has not been detected in any other animal species.

In infants and young children (under 5 years of age), Haemophilus influenzae type b causes bacteremia and acute bacterial meningitis Occasionally, it causes epiglottitis (obstructive laryngitis), cellulitis, osteomyelitis, and joint infections. Nontypable H. influenzae causes ear infections (otitis media) and sinusitis in children. Initially H. influenzae invades the nasopharyngeal mucosa before spreading to the lower respiratory tract where the organism invades and destroys the mucous membranes producing bronchiolitis, peribronchiolitis, and/or interstitial lesions and is associated with respiratory tract infections (pneumonia).

In 1995, Haemophilus influenzae was the first free-living organism to have its entire chromosome sequenced.

References:

http://www.bact.wisc.edu/Bact330/lectureHflu