Table 2.

Antiviral effects of Bifidobacterium spp.

Reference	Strain(s)	Outcomes and results	Discussion
Gagnon et al. [17]	B. thermophilum, B. thermacido-philum, B. longum, B. pseudolongum	• Inhibition of adherence of rotavirus to Caco-2 and HT-29 cells after pretreatment with B. thermophilum • Number of rotavirus, duration of diarrhea, and epithelial lesion decreased after treatment with B. thermophilum	Bifidobacteria contributed to the inhibition of rotavirus infections, and ultimately resulted in reduced transmission
Ishizuka et al. [18]	B. infantis, B. breve	• Controlled release of antiviral substances • Rotaviral infectivity of PIE cells decreased with B. infantis or B. breve pretreatment	It is possible to replace antiviral drugs with a bifidobacteria formula to inhibit rotavirus infections in animals
Vlasova et al. [19]	L. rhamnosus, B. animalis	• Virus shedding titer decreased • Viral diarrhea period reduced	Diarrhea of neonatal gnotobiotic pig by human rotavirus was mitigated
Muñoz et al. [20]	B. longum subsp. infantis	• Virus shedding decreased • Fecal sIgA increased	B. infantis showed an initial protective effect against infection with the murine rotavirus McN strain
Holscher et al. [21]	B. lactis	• Fecal anti-rotaviral and anti-polioviral IgA increased after vaccination	The lack of immunity in infants not breastfed or delivered by cesarean sectioning was mitigated by safely introducing immune-controlling bacteria through a Bb12 formula

IgA, immunoglobulin A; PIE, porcine intestinal epitheliocytes.