Fusobacterium necrophorum

Fusobacterium necrophorum

Fusobacterium necrophorum
Scientific classification
Domain: Bacteria
Phylum: Fusobacteria
Order: Fusobacteriales
Family: Fusobacteriaceae
Genus: Fusobacterium
Species: F. necrophorum
(Flügge 1886) Moore and Holdeman 1969[1]

Fusobacterium necrophorum is a species of bacteria responsible for Lemierre's syndrome and other medical problems.


  • Biology 1
  • Pathogenicity 2
    • Treatment 2.1
    • Infection in animals 2.2
  • References 3
  • Further reading 4


F. necrophorum is a rod-shaped species of Gram-negative bacteria. It is an obligate anaerobe and is a common inhabitant of the alimentary tract within humans and animals.[2]


F. necrophorum is responsible for 10% of acute sore throats,[3] 21% of recurrent sore throats[4][5] and 23% of peritonsillar abscesses[6] with the remainder being caused by Group A streptococci or viruses. Other complications from F. necrophorum include meningitis, complicated by thrombosis of the internal jugular vein, thrombosis of the cerebral veins,[7] and infection of the urogenital and the gastrointestinal tracts.[8]

Although this infection is rare, researchers agree that this diagnosis should be considered in a septicaemic patient with thrombosis in an unusual site, and underlying malignancy should be excluded in cases of confirmed F. necrophorum occurring at sites caudal to the head.[9]

The above statistical analysis is dated, necessarily. A 2015 study of young adult students presenting to a single clinic in Alabama had F. necrophorum as the predominate causative organism for pharyngitis 21% of the time (and found in 9% of asymptomatic students).[10] In the same study, Group A Streptococcus was found in 10% of pharyngitis patients (1% of asymptomatic students).


F. necrophorum infection (also called F-throat[11]) usually responds to treatment with penicillin or metronidazole, but penicillin treatment for persistent pharyngitis appears anecdotally to have a higher relapse rate, although the reasons are unclear.

Infection in animals

This bacterium has been found to be associated with the foot disease thrush in horses. Thrush is a common fungal infection that occurs on the hoof of a horse, specifically in the region of the frog. F. necrophorum occurs naturally in the animal's environment, especially in wet, muddy, or unsanitary conditions, such as an unclean stall.[12] [13] Horses with deep clefts, or narrow or contracted heels are more at-risk to develop thrush.

F. necrophorum is also a cause for lameness in sheep. Its infection is commonly called scald. It can last for several years on land used by either sheep or cattle, and is found on most land of this type throughout the world. Due to its survival length in these areas, it is unrealistic to try to remove it. Sheep most often get scald due to breakage or weakness of the skin surrounding the hoof. This can occur due to strong footbaths, sandy soils, mild frostbite, or prolongened waterlogging of a field, and results in denaturing of the skin between the cleats.[14]

F. necrophorum is the cause of necrotic laryngitis ("calf diphtheria") in cattle.


  1. ^ J.P. Euzéby. "Fusobacterium". List of Prokaryotic names with Standing in Nomenclature. Retrieved 2012-05-09. 
  2. ^ Tan, Z. L.; Nagaraja, T. G.; Chengappa, M. M. "Fusobacterium necrophorum infections: Virulence factors, pathogenic mechanism and control measures". Veterinary Research Communications 20 (2): 113–140.  
  3. ^ Aliyu SH, Marriott RK, Curran MD; et al. (2004). "Real-time PCR investigation into the importance of Fusobacterium necrophorum as a cause of acute pharyngitis in general practice". J Med Microbiol 53 (Pt 10): 1029–35.  
  4. ^ Batty A, Wren MW. (2005). "Prevalence of Fusobacterium necrophorum and other upper respiratory tract pathogens isolated from throat swabs". Br J Biomed Sci 62 (2): 66–70.  
  5. ^ Batty A, Wren MW, Gal M. (2004). "Fusobacterium necrophorum as the cause of recurrent sore throat: comparison of isolates from persistent sore throat syndrome and Lemierre's disease". J Infect 51 (4): 299–306.  
  6. ^ Klug TE, Rusan M, Fuursted K, Ovesen T (2009). "Fusobacterium necrophorum: most prevalent pathogen in peritonsillar abscess in Denmark.". Clin Infect Dis 49 (10): 1467–1472.  
  7. ^ Larsen PD, Chartrand SA, Adickes M. (1997). "Fusobacterium necrophorum meningitis associated with cerebral vessel thrombosis.". Pediatr Infect Dis J 16 (3): 330–331.  
  8. ^ Hagelskjaer Kristensen L, Prag J. (200). "Human necrobacillosis, with emphasis on Lemierre's syndrome.". Clin Infect Dis 31 (2): 524–532.  
  9. ^ Redford ML, Ellis R, Rees CJ. (2005). "Fusobacterium necrophorum infection associated with portal vein thrombosis.". J Med Microbiol 54 (5): 993–995.  
  10. ^ Robert M. Centor, MD; T. Prescott Atkinson, MD, PhD; Amy E. Ratliff, MLS; Li Xiao, PhD; Donna M. Crabb, MT (ASCP); Carlos A. Estrada, MD, MS; Michael B. Faircloth, MD; Lisa Oestreich, DO; Jeremy Hatchett, MD; Walid Khalife, PhD; and Ken B. Waites, MD (2015). "The Clinical Presentation of Fusobacterium-Positive and Streptococcal-Positive Pharyngitis in a University Health Clinic: A Cross-sectional Study". Ann Intern Med 162 (4): 241–247.  
  11. ^ "Sore Throat Misdiagnosis Could Kill Teenagers".  
  12. ^ https://www.thehorse.com/articles/27319/the-lowdown-on-thrush
  13. ^ Ensminger, M. E. (1990). Horses and Horsemanship: Animal Agriculture Series (Sixth ed.). Danville, IL: Interstate Publishers. p. 62.  
  14. ^ http://www.defra.gov.uk/animalh/welfare/pdf/sheeplameness.pdf

Further reading