The role of microbiota in pathogenesis and development of viral infections

Abstract

Introduction and purpose
 The microbiota plays an important role in human metabolism, immune system, and development of many chronic diseases, cancers, and infectious diseases. The aim of the study is to present the role of gut microbiota in viral infections, including HBV, Herpesviridae, HIV, and SARS-CoV-2. The newest publications from the last 5 years available on the PubMed database were taken into account.
 A brief description of the state of knowledge
 The mechanism by which bacterias have an impact on viral infection is based on a synthesis of specific short-chain fatty acids (SCFAs) and modulation of cytokine release and immune system function by bacterias. Domination of Gardnerella vaginalis and lack of Lactobacillus in the vaginal microbiome increased the risk of HSV-2 infection in women. Inflammation of the genital tract can influence susceptibility to HIV infection, but probiotics via enhancement of the gut barrier integrity, change TH17/Treg ratio, can restore microbiome composition. LPS - component of the structure of Gram-negative bacteria can be a marker of HBV infection. In the airway microbiome of patients with COVID-19 opportunistic microorganisms were identified.
 Conclusions 
 Diet, intake of probiotics, fecal microbiota transplantation (FMT) are interventions that might be efficient methods in prophylaxis and treatment of viral diseases. Further studies are needed to evaluate the mechanism of action of microbiome in pathogenesis of infectious diseases.