A subspecies of Bifidobacterium longum that occurs in the GASTROINTESTINAL TRACT of human infants and is used as a PROBIOTIC. It may also be used in the treatment of IRRITABLE BOWEL SYNDROME.

Synonyms: Bifidobacterium longum ssp. infantis, Bifidobacterium longum subspecies infantis, Bifidobacterium infantis, txid1682