我s the Difference Between Haemophilus Influenzae and Haemophilus Parainfluenzae

Thekey difference between Haemophilus influenzae and Haemophilus parainfluenzaeis thatHaemophilus influenzaeis agammaproteobacteriumthat requires both hermin (factor X) and NAD+ (factor V) for its growth, whileHaemophilus parainfluenzaeis a gammaproteobacterium that requires only NAD+ (factor V) for its growth.

Haemophilusis a genus ofgram-negative, pleomorphic and coccobacilli bacteria. This genus belongs to the family Pasteurellaceae. These species inhabit the mucous membranes of the upper respiratory tract, mouth, vagina, and intestinal tract. All members of this genus are either aerobic orfacultative anaerobic. This genus has bothcommensal and pathogenicspecies. Some of the well-known species in this genus areHaemophilus influenzae,Haemophilus parainfluenzae,Haemophilusducreyi,Haemophilus haemolyticusandHaemophilus aegyptius.H. influenzaeandH. parainfluenzaeare two pathogenic species of this genus.

1.Overview and Key Difference
2.我s Haemophilus Influenzae
3.我s Haemophilus Parainfluenzae
4.Similarities – Haemophilus Influenzae and Haemophilus Parainfluenzae
5.Haemophilus Influenzae vs Haemophilus Parainfluenzae in Tabular Form
6.Summary – Haemophilus Influenzae vs Haemophilus Parainfluenzae

我s Haemophilus Influenzae?

Haemophilus influenzaeis a gammaproteobacterium that requires both hermin (factor X) and NAD+ (factor V) for its growth. It is a gram-negative, coccobacillary, facultative anaerobic bacterium.H. influenzae是一个famil capnophilic致病性细菌y Pasteurellaceae. This bacterium was described by Richard Pfeiffer in 1892 during an influenza pandemic. This bacterial species was the first free-living organism to have its entire genome sequenced. In 1930,H. influenzaewas divided into two types of strains: unencapsulated and encapsulated. Encapsulated strains were classified into six groups based on their capsular antigens: a, b, c, d, e, f. Encapsulated strains are also known as typable strains. Unencapsulated strains are termed as non-typable (NTHi) because they lack capsular serotypes. However, they can be classified through multilocus sequence typing.

Haemophilus Influenzae vs Haemophilus Parainfluenzae in Tabular Form

Figure 01: Haemophilus influenzae

H. influenzaetype b (Hib) is a lethal strain that causes bacteremia, pneumonia, epiglottitis, acute bacterial meningitis, cellulitis, osteomyelitis and infectious arthritis. Antibiotics such as cefotaxime, ceftriaxone, ampicillin, sulbactam, cephalosporin, macrolides, and fluoroquinolones are effective againstH. influenzae. Moreover, infections that are caused by encapsulated strains ofH. influenzaeare greatly reduced by the Hib vaccine.

我s Haemophilus Parainfluenzae?

Haemophilus parainfluenzaeis a gammaproteobacterium that requires only NAD+ (factor V) for its growth. It is also a gram-negative, facultatively anaerobic coccobacillus. It is a part of the HACEK group that causes 3% of infective endocarditis cases. HACEK organisms are a group of fastidious gram-negative bacteria. They are an unusual cause of infective endocarditis. HACEK group include different genera suchHaemophilus,Aggregatibacter,Cardiobacterium,EikenellaandKingella, etc. Moreover,H. parainfluenzaeis an opportunistic pathogen that has been associated with endocarditis, bronchitis, conjunctivitis, pneumonia, otitis, abscesses, and genital tract infections.H. parainfluenzaebiotypes I and II are capable of natural genetic transformation. Most of the isolates are sensitive to ampicillin. Moreover, some strains produce beta-lactamases.

Similarities Between Haemophilus Influenzae and Haemophilus Parainfluenzae

influenzaeandH. parainfluenzaeare two pathogenic species of the genusHaemophilus.
Both species are gammaproteobacteria.
They belong to the family Pasteurellaceae.
These bacteria are gram-negative, facultatively anaerobic, coccobacilli.
Both species are pathogenic.
They have a single chromosome.

Difference Between Haemophilus Influenzae and Haemophilus Parainfluenzae

H.influenzaeis a gammaproteobacterium that requires both hermin (factor X) and NAD+ (factor V) for its growth. In contrast,H. parainfluenzaeis a gammaproteobacterium that requires only NAD+ (factor V) for its growth. So, this is the key difference between Haemophilus influenzae and Haemophilus parainfluenzae. Furthermore,H. influenzaegrows on chocolate agar but not on blood agar, whileH. parainfluenzaegrows on blood agar.

The below infographic lists the differences between Haemophilus influenzae and Haemophilus parainfluenzae in tabular form for side by side comparison.

Summary – Haemophilus Influenzae vs Haemophilus Parainfluenzae

Haemophilusis a genus of gram negative, pleomorphic and coccobacilli bacteria. These bacteria are gammaproteobacteria. This genus has both commensal and pathogenic species.Haemophilus influenzaeandHaemophilus parainfluenzaeare two pathogenic species of the genus Haemophilus.Haemophilus influenzaerequires both hermin (factor X) and NAD+ (factor V) for its growth. ButHaemophilus parainfluenzaerequires only NAD+ (factor V) for its growth. Thus, this is the summary of the difference between Haemophilus influenzae and Haemophilus parainfluenzae.

Reference:

1. Musher, Daniel M. “Haemophilus Species.” Medical Microbiology. 4th Edition., U.S. National Library of Medicine, 1 Jan. 1996.
2. “HaemophilusParainfluenzae.” An Overview | ScienceDirect Topics.