BACKGROUND: Viral respiratory infections could result in perturbation of the gut microbiota due to a probable cross-talk between lungs and gut microbiota . This can affect the pulmonary health and the gastrointestinal system .
OBJECTIVE: This review aimed to discuss the impact of probiotics/ prebiotics and supplements on the prevention and treatment of respiratory infections, especially emerging pathogens .
METHODS: The data were searched were searched in PubMed, Scopus, Google Scholar, Google Patents, and The Lens-Patent using keywords of probiotics and viral respiratory infections in the title, abstract, and keywords . RESULT: Probiotics consumption could decrease the susceptibility to viral respiratory infections, such as COVID-19 and simultaneously enhance vaccine efficiency in infectious disease prevention through the immune system enhancement . Probiotics improve the gut microbiota and the immune system via regulating the innate system response and production of anti-inflammatory cytokines . Moreover, treatment with probiotics contributes to the intestinal homeostasis restitution under antibiotic pressure and decreasing the risk of secondary infections due to viral respiratory infections . Probiotics present varied performances in different conditions; thus, promoting their efficacy through combining with supplements (prebiotics, postbiotics, nutraceuticals, berberine, curcumin, lactoferrin, minerals, and vitamins) is important . Several supplements reported to enhance the probiotics' efficacy and their mechanisms as well as probiotics related patents are summarized in this review . Using nanotechnology and microencapsulation techniques can also improve probiotics efficiency .
CONCLUSION: Given the global challenge of COVID-19, probiotic/prebiotic and following nutritional guidelines should be regarded seriously . Additionally, their role as an adjuvant in vaccination for immune response augmentation needs attention.