Abstract: HYPOTHESIS AND THEORY published: 11 July 2022 doi: 10.3389/fmicb.2022.952321 Microbiome-Based Hypothesis on Ivermectin’s Mechanism in COVID-19: Ivermectin Feeds Bifidobacteria to Boost Immunity Sabine Hazan* Progenabiome, LLC, Ventura, CA, United States Edited by: Mohammad Yousef Alikhani, Hamadan University of Medical Sciences, Iran Reviewed by: Amir Khodavirdipour, University of Tabriz, Iran Piyush Baindara, University of Missouri, United States *Correspondence: Sabine Hazan DrHazan@progenabiome.com Specialty section: This article was submitted to Infectious Agents and Disease, a section of the journal Frontiers in Microbiology Received: 25 May 2022 Accepted: 10 June 2022 Published: 11 July 2022 Citation: Hazan S (2022) Microbiome-Based Hypothesis on Ivermectin’s Mechanism in COVID-19: Ivermectin Feeds Bifidobacteria to Boost Immunity. Front. Microbiol. 13:952321. doi: 10.3389/fmicb.2022.952321 Ivermectin is an anti-parasitic agent that has gained attention as a potential COVID-19 therapeutic. It is a compound of the type Avermectin, which is a fermented by-product of Streptomyces avermitilis. Bifidobacterium is a member of the same phylum as Streptomyces spp., suggesting it may have a symbiotic relation with Streptomyces. Decreased Bifidobacterium levels are observed in COVID19 susceptibility states, including old age, autoimmune disorder, and obesity. We hypothesize that Ivermectin, as a by-product of Streptomyces fermentation, is capable of feeding Bifidobacterium, thereby possibly preventing against COVID-19 susceptibilities. Moreover, Bifidobacterium may be capable of boosting natural immunity, offering more direct COVID-19 protection. These data concord with our study, as well as others, that show Ivermectin protects against COVID-19. Keywords: microbiome, COVID-19, SARS-CoV-2, Bifidobacterium, TNF-α (tumor necrosis factor a), ivermectin