IL, interleukin(3) Probiotics(2) NK, natural killer(2) IFN-γ, Interferon-gamma(2) COVID-19(2) ACE2, angiotensin-converting enzyme 2(2) CRP, C-reactive protein(2) GCSF, Granulocyte colony-stimulating factor(2) Th1/2, T-helper cells type 1 and 2(2) SARS-CoV-2, Severe acute respiratory syndrome coronavirus 2(2) respiratory viral infection(2) Lactobacillus (2) OAS, Oligoadenylate synthetase(2) SARS-CoV-2(2) MERS-CoV, Middle East respiratory syndrome coronavirus(2) TNF, Tumor Necrosis Factor(2) IFV, influenza A virus(2) Influenza virus(2) WHO, World Health Organization(2) COVID-19, coronavirus disease(2) RVI, Respiratory virus infections(2) Bcl-2, B-cell lymphoma 2(1) observational prospective cohort study(1) MT, metallothionein(1) GMT(1) Th, T helper cell(1) OR(1) ACE2, Angiotensin-converting enzyme-2(1) influenza A virus(1) NK cells, Natural Killer cells(1)