Safety Assessment in Bifidobacteria

Bifidobacteria can be considered to be very safe to humans since no cases where a probiotic bifidobacterial product has caused an infection have been reported. Also bifidobacteria belonging to the resident microbiota of the oro-gastrointestinal tract very rarely cause infections. Oral bifidobacterial species should, however, be avoided in probiotic products, since these are considered to be oral pathogens and they have also occasionally caused infections. Probiotic Bifidobacterium strains should be chosen among the species that either have previously been commonly used in probiotic human products or represent the commonly detected species in the human gastrointestinal tract (GIT). In addition, safety assessment of a Bifidobacterium strain should involve at least diverse phenotypic characterisation of the strain (to indicate whether it is a typical representative of the species), antibiotic resistance pattern assessment (some strains might carry acquired resistance genes and these should be avoided), and assessment of side effects during human studies. Finally, an epidemiological surveillance of adverse incidents in consumers (post-market) should be performed at a later stage. Qualified Presumption of Safety (QPS) and its four pillars of safety assessment should be the basis of the safety evaluation of probiotics, although QPS is currently applied only to bacteria added to feed and used as biocontrol agents in EU.