Table 1.

Probiotics associated with treatment of viral infections.

Probiotic	Condition	Concentration	Evidence	Ref
B. subtilis and S. faecium (Medilac-DS)	Pneumonia	1 × 109 CFU	In human trials, improved clinical symptoms and normalized inflammatory biomarker levels (hs-CRP) in patients with pneumonia	[16]
L. acidophilus DSM 32241, L. plantarum DSM 32244, L. helveticus DSM 32242, L. brevis DSM 27961, L. paracasei DSM 32243, B. lactis DSM 32246, B. lactis DSM 32,247, and S. thermophilus DSM 32345	COVID-19	2.4 × 1010 CFU	In human trials, improve clinical symptoms, such as remission of diarrhea, reduces mortality, and decreased the risk of developing respiratory failure	[17]
L. rhamnosus HN001, L. acidophilus DDS-1 and B. lactis Bb-12, and S. thermophilus	Upper respiratory tract infection	1010, 5 × 1010, and 107 CFU	Human trials, indicating a reduction in respiratory tract infections improved quality of life	[18,19]
L. lactis JCM 5805	Influenza and common cold	1011 CFU	In healthy young adults, decreased the incidence, reduced the number of days of symptoms associated with influenza and common cold through the activation of plasmacytoid dendritic cells and upregulation of IFN-related genes	[20]
L. delbrueckii subsp. bulgaricus OLL1073R-1	Influenza A virus subtype H3N2	1.8–3.5 × 108 CFU	In human elderly patients improved immunity, prevented infection with influenza A virus subtype H3N2 via the production of influenza A virus subtype of H3N2-bound salivary IgA	[21]
L. paracasei N1115	Acute upper respiratory tract infections	3.6 × 107 CFU	In human elderly and middle-aged patients reduced the risk of acute upper tract infections via T-cell natural immune defense stimulation	[22]
L.rhamnosus GG, live B. subtilis, E. faecalis, B. breve Yakult, L. casei Shirota	Ventilator assisted Pneumonia	2 × 109, 4.5 × 109 and 0.5 × 109, and 1 × 108 CFU	Human trials indicated substantially less incidence of ventilator-associated pneumonia	[15,23,24]