RT Journal Article T1 Probiotic Effects against Virus Infections: New Weapons for an Old War A1 López Santamarina, Aroa A1 Lamas Freire, Alexandre A1 Mondragón Portocarrero, Alicia del Carmen A1 Cardelle Cobas, Alejandra A1 Regal López, Patricia A1 Rodríguez Ávila, José Antonio A1 Miranda López, José Manuel A1 Franco Abuín, Carlos Manuel A1 Cepeda Sáez, Alberto K1 Probiotic K1 Gut microbiota K1 Viral infection K1 Viruses K1 Influenza AB This review aimed to gather the available literature investigating the effects of probiotics against the most common viral infections using in vitro trials in cell lines and in vivo clinical trials in both experimental animals and humans. Probiotics were employed to prevent and reduce symptoms of infections caused by common viruses, especially respiratory tract viruses, but also for viral digestive infections (such as rotavirus, coronavirus, or norovirus) and other viral infections (such as viruses that cause hepatitis, human papillomavirus, human immunodeficiency virus, and herpes simplex virus). Different probiotics have been studied to see their possible effect against the abovementioned viruses, among which different Lactobacillus species, Bifidobacterium, Clostridium, Enterococcus, and Streptococcus can be highlighted. In many cases, mixtures of various probiotic strains were used. Although the results obtained did not show similar results, in most cases, probiotic supplementation improved both barrier and biochemical immune responses, decreased susceptibility to viral infections, and enhanced the effects of concomitant vaccines. Works collected in this review show a beneficial effect of probiotics in the prevention and treatment of different viral infections. We found interesting results related to the prevention of viral infections, reduction of the duration of diseases, and decrease of symptoms PB MDPI YR 2021 FD 2021 LK http://hdl.handle.net/10347/24173 UL http://hdl.handle.net/10347/24173 LA eng NO Lopez-Santamarina, A.; Lamas, A.; del Carmen Mondragón, A.; Cardelle-Cobas, A.; Regal, P.; Rodriguez-Avila, J.A.; Miranda, J.M.; Franco, C.M.; Cepeda, A. Probiotic Effects against Virus Infections: New Weapons for an Old War. Foods 2021, 10, 130 NO The authors thank the European Regional Development Funds (FEDER), grant ED431C 2018/05, and Programa Iberoamericano de Ciencia y Tecnología para el Desarrollo (CyTED), grant PCI2018-093245 for covering the cost of publication DS Minerva RD 3 may 2026