Viral Infections, the Microbiome, and Probiotics

Abstract

Viral infections continue to cause considerable morbidity and mortality around the world. Recent rises in these infections are likely due to complex and multifactorial external drivers, including climate change, the increased mobility of people and goods and rapid demographic change to name but a few. In parallel with these external factors, we are gaining a better understanding of the internal factors associated with viral immunity. Increasingly the gastrointestinal (GI) microbiome has been shown to be a significant player in the host immune system, acting as a key regulator of immunity and host defense mechanisms. An increasing body of evidence indicates that disruption of the homeostasis between the GI microbiome and the host immune system can adversely impact viral immunity. This review aims to shed light on our understanding of how host-microbiota interactions shape the immune system, including early life factors, antibiotic exposure, immunosenescence, diet and inflammatory diseases. We also discuss the evidence base for how host commensal organisms and microbiome therapeutics can impact the prevention and/or treatment of viral infections, such as viral gastroenteritis, viral hepatitis, human immunodeficiency virus (HIV), human papilloma virus (HPV), viral upper respiratory tract infections (URTI), influenza and SARS CoV-2. The interplay between the gastrointestinal microbiome, invasive viruses and host physiology is complex and yet to be fully characterized, but increasingly the evidence shows that the microbiome can have an impact on viral disease outcomes. While the current evidence base is informative, further well designed human clinical trials will be needed to fully understand the array of immunological mechanisms underlying this intricate relationship.

In silico identification and experimental validation of cellular uptake by a new cell penetrating peptide P1 derived from MARCKS

“…Preventive and therapeutic vaccines have promising applications to prevent infection and treat cancer and other health issues globally (Harper et al, 2020 ). Although several vaccines against human papillomavirus (HPV), viral hepatitis, influenza, measles, varicella, rubella, mumps and rotavirus (Knuf et al, 2008 ) have been widely used to save millions of lives, vaccines for newly discovered pathogens like the respiratory virus COVID 19 are urgently needed (Du et al, 2018 ).…”

Efficacy and safety of novel probiotic formulation in adult Covid19 outpatients: a randomized, placebo-controlled clinical trial

“…Intestinal bacteria can potentially achieve distal effects on lung homeostasis through training of immune cells in the gut epithelium and their subsequent migration to the pulmonary epithelium, and/or through the permeation into the bloodstream of bacterial metabolites having distal immunomodulatory effects. 5,6…”

Physical Activity and Nutritional Influence on Immune Function: An Important Strategy to Improve Immunity and Health Status

“…In this context, conflicting reports showed the ineffectiveness of carbohydrate supplementation to minimize URTI risk . While animal models have shown that a carbohydraterich diet reduces the risk of herpes simplex virus 1 [HSV-1] infection and mortality (Harper et al, 2021), it has also been shown that carbohydrate intake after exercise debilitates human T cells' declining migration towards human rhinovirus-infected airway epithelial cells, as seen in vitro (Peake et al, 2017). Therefore, more research regarding the effectiveness of carbohydrate supplementation with clinical relevance in a case like URTI is required.…”

“…• Minimized exercise-induced increased circulating cytokines, redistribution of immune cells like neutrophils, monocytes, NK cells and lymphocytes (Nieman and Wentz, 2019). • Upper respiratory tract infections (URTI) recovery (Nieman and Mitmesser, 2017); reduction in risk of infection and mortality from viral infections like herpes simplex virus 1 [HSV-1] (Harper et al, 2021). Micronutrients including (antioxidant vitamins-vitamins C and E); vitamin D and multivitamin…”