Probiotics have shown an antiviral activity and several mechanisms have been demonstrated. In respiratory tract infections (RTIs), the majority of probiotics can inhibit the most important respiratory viruses by immunomodulatory mechanisms. There are over 200 different types of viruses, which cause RTIs in humans. Human rhinoviruses (HRV) are the largest group of respiratory viruses, comprising over 150 serotypes. In humans, the predominant illness caused by HRV is the acute upper RTI, also known as the common cold. The second most common viruses infecting humans are the human enteroviruses (HEV), which are associated with clinical manifestations ranging from mild respiratory symptoms to serious conditions. Influenza viruses, respiratory syncytial virus (RSV), and adenoviruses are also major causative agents of both upper and lower RTIs. In addition, many other viruses or virus groups cause RTIs, e.g., parainfluenza viruses and coronaviruses can cause a broad spectrum of respiratory diseases, ranging from mild upper RTIs to pneumonia. In recent years, with the rapid development of high-throughput molecular techniques, several new viruses associated with respiratory diseases, such as human bocavirus, human metapneumovirus, and the new coronaviruses HKU1 and NL63, have been identified as well. Recently, COVID-19 had cause huge effect worldwide. With this, to reduce the burden and severity of this pandemic, the use of probiotic in preventing of COVID-19 has been ongoing. Probiotics also had given out significant outcome in gastroenteritis infections where a study suggested that probiotics had be effective in alleviating the duration and severity of acute rotavirus gastroenteritis. Apart from this, for viruses that cause hepatitis, skin virus infections, human immunodeficiency virus (HIV), or HPV, probiotics could directly or indirectly, help reduce their symptoms or prevent infection.~Probiotics are known as a good natural non-drug, which was widely used to boost immune cells in host to fight against infection. Generally, probiotic effects are mediated through immune regulation, particularly through balance control of proinflammatory and anti-inflammatory cytokines. The immune response is initiated by innate immunity following exposure to foreign substances or tissue injury. Innate immunity exerts protective roles in host homeostasis in part by priming adaptive immune responses against persisting insults and inducing inflammation. However, the unbalanced immune response leads to severe inflammation and uncontrolled tissue damage and disease. Probiotics have been found to enhance the innate immunity and modulate pathogen-induced inflammation via toll-like receptor-regulated signaling pathways.
The purpose of this study is to evaluate the efficacy of oral administration of probiotic at 9 log colony forming unit (CFU)/day to reduce vaginal abundance of HPV in women compared to placebo via the use of vaginal self-swab.