Fusobacterium

Fusobacterium is a genus of obligate anaerobic, Gram-negative, non-sporeforming bacteria belonging to Gracilicutes. Individual cells are slender, rod-shaped bacilli with pointed ends. Fusobacterium was discovered in 1900 by Courmont and Cade and is common in the flora of humans. Strains of Fusobacterium can cause several human diseases and infections, including periodontal diseases, Lemierre's syndrome, oral, head, and neck infections, as well as colorectal cancer and topical skin ulcers. It has also been tied to HIV infection and suboptimal immune recovery. Detection of Fusobacterium is typically through surgical retrieval of tissue as well as testing of fecal matter and blood given the patient is showing symptoms. Early detection is preferred and best to avoid further development. Although older sources state that Fusobacterium is part of the normal flora of the human oropharynx, the current consensus is that Fusobacterium should always be treated as a pathogen. Fusobacterium currently has 13 strains; the main one affecting humans is F. nucleatum while F. necrophorum follows as well as affecting animals, mainly cattle. Courmont and Cade discovered Fusobacterium in 1900. However, the first documented infection of Fusobacterium was in 1898 by Veillon and Zuber, which included a human systemic infection of a young child. However, the genus was not proposed until Knorr in 1923. Fusobacterium is not alien and is actually a normal part of every human's oral, gastrointestinal, and (female) genital flora which is why infections are not commonly seen. Fusobacterium is often associated with ulcerative colitis. Research of colon cancer has also shown an overrepresentation of Fusobacterium, both in feces of patients and tumor issue itself. Fusobacterium has also been seen increased in individuals infected with HIV as well as in individuals with suboptimal immune recovery as compared to patients who were not infected and had optimal responses. F. nucleatum is found in humans more so than any other species of Fusobacterium.