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The ENT microbiota

The ENT microbiota is an extremely diverse microbiota which is assumed to include at least 700 different species.

In the mouth, it is primarily found on the tongue, mucous  membranes, gums, and teeth, as well as in the saliva. Predominant phyla are Actinobacteria, Bacteroidetes, Firmicutes, Proteobacteria, and Synergistetes1 , and primary genera are Streptococcus, Veillonella, Granulicatella, Granulicatella, Actinomyces, Corynebacterium, etc2.

In the nasal cavity, Actinobacteria and Firmicutes are predominant, with the occasional presence of Proteobacteria: Corynebacteriaceae and Propionibacteriaceae are the dominant families3.

In the ear, it was long believed that the area was exempt from any microbiota (because it was sterile), but since then a relatively diverse population of bacteria has been observed in the middle ear, with a predominance of Pseudomonadaceae4 . Recent studies have also shown evidence of the presence of Alloiococcus otitis5,6 , Corynebacterium otitidis5,6 , and Turicella otitidis6 . Although these bacteria are found in middle ear infections, their role in healthy individuals has yet to be elucidated, but it seems as though the ear canal might be a reservoir of infection for the middle ear7 .

Dysbiosis and ENT diseases

An imbalance in the oral microbiota is at the root of diseases like cavities, gingivitis, and periodontitis, which are possible to prevent by fighting against the biofilm concentrating these pathogenic bacteria2. Nasal microbiota is being investigated to understand its possible involvement in sinusitis, while more studies are needed to fully identify the role of the bacteria present in the ear.

1 – Wade WG. Detection and culture of novel oral bacteria. Chap. 2 de Oral microbial ecology – current research and new perspectives. Caister Academic Press, Norfolk (2013)
2 – Zarco et al. The oral microbiome in health and disease and the potential impact on personalized dental medicine. Oral Diseases 2012 ; 18 : 109-120.
3 – Bassis C et al. The nasal cavity microbiota of healthy adults. Microbiome 2014. 2 :27.
4 – Liu CM et al. The otologic microbiome. Arch Otolaryngol Head Neck Surg 2011. 137(7) : 664-668.
5 – Franck DN et al. Culture-independent molecular analysis of microbial constituents of the healthy human outer ear. J Clin Microbiol. 2003 Jan;41(1):295-303.
6 – Stroman DW et al. Microbiology of normal external auditory canal. Laryngoscope. 2001 Nov ; 111(11 Pt 1) : 2054-9.
7 - Chan CL et al. Identification of the Bacterial Reservoirs for the Middle Ear Using Phylogenic Analysis. JAMA Otolaryngol Head Neck Surg. 2017 Feb 1;143(2):155-161.



Dysbiosis can cause multiple pathologies with repercussions on different organs.

Affecting the microbiota

There is 1 way to affect the equilibrium of microbiota.

  • Probiotics

    The WHO defines probiotics as “live microorganisms which, when administered in adequate amounts, confer a health benefit on the host”.

The various microbiota

Intestinal microbiota

The intestinal microbiota is an organ in its own right.
Better characterized thanks to metagenomics, it is gradually giving up its secrets. Highly diversified, it lives in close relationship with its host. Formed from birth, it is specific to each individual and fulfills different functions within the body: barrier effect, trophic, metabolic and immune functions, etc., as well as others that remain to be elucidated.


Vaginal microbiota

The vaginal microbiota is an ecosystem constituted of microorganisms, where the genus Lactobacillus predominates. Its equilibrium is fragile and changes in its composition cause infections.


ENT microbiota

The ENT microbiota is an extremely diverse microbiota which is assumed to include at least 700 different species.


Cutaneous microbiota

Cutaneous microbiota is extremely diverse. Its composition varies according to the cutaneous zone and between individuals, and its imbalance is associated with skin diseases.


Pulmonary microbiota

The pulmonary microbiota was unknown for a long time, since it was commonly accepted that healthy lungs are sterile. This paradigm was cast into doubt with the discovery of the various human microbiota.


Urinary microbiota

The urinary microbiota was discovered very recently and has only begun to be described. Imbalances in this flora may be associated with problems in the urinary tract.

Biocodex Microbiota Institute overview

The Biocodex Microbiota Institute: an international leader in microbiota