The Potential Use of Probiotics in Coronavirus Disease (COVID-19)
The objective of this report is to assess current available evidence on the potential of probiotics in COVID-19 management based on the following:
- Efficacy: Focus on probiotics’ reported properties of 1: antiviral, 2: modulation of immune response, and 3: role as other supportive therapy or management of disease related complications; and their respective potential mechanism(s) of actions.
- Safety of probiotics
Electronic databases were searched using pre-determined terminologies such as ‘probiotics’, ‘antiviral’, immunomodulatory’, ‘immune response’, ‘mechanism of action’, and ‘safety’. All clinical and preclinical studies (both in vitro and in vivo) related to safety and efficacy or effectiveness of probiotics in treating viral diseases were included.
Results and discussion:
Based on literature search, evidence which consists of human trials, in vivo and in vitro studies showed antiviral effects of probiotics, as well as immunomodulatory effects contributing towards indirect antiviral effects. However, most efficacy studies investigated influenza and upper respiratory infections, which were not specific towards SARS-CoV-2 virus. Many factors can influence efficacy, including the type of probiotic strain (Lactobacillus spp. as the most studied species), mechanism of action (twelve possible mechanisms), and dosage. A recent study on current management of COVID-19 in Zhejiang, China reported probiotics being used as supportive treatment for intestinal microbial dysbiosis complications caused by SARS-CoV-2 virus.
Based on literature search, probiotics showed potential antiviral and immunomodulatory effects, though not specific towards SARS-CoV-2 virus. Further investigation is required to explore these potentials in COVID-19 management. Although probiotics are considered to be generally safe for human consumption, special safety considerations must be given to the critically-ill such as intensive care unit (ICU) patients, where there were reports on increased risk of bacteraemia. It is important that pathogenicity and infectivity, intrinsic properties, as well as virulence factors related to toxicity and metabolic activity of the microorganisms be clearly studied.