Microbiome protection against <i>Coccidioides</i>growth

Abstract During infection, the host utilizes multiple mechanisms to prevent colonization and dissemination. Protection begins at surface, often via commensal community found within our respiratory, skin, intestinal tract. Microbiota disruption reduces effectiveness of this protective barrier. Coccidioidomycosis, or Valley fever, is misdiagnosed as acquired bacterial pneumonia treated with antibiotics that alter microbiota density diversity. Commensal bacteria influence immune responses antibiotic treatment alters immunity. A soil microbial antagonist related Bacillus subtilis inhibits in vitro growth Coccidioides through a clear zone inhibition between fungi bacteria. Whether also unknown. To assess if has capabilities against Coccidioides, we performed two assays measured area. 50/50 assay was which were placed direct competition on agar plates. spike where grown 80% confluency, mimic an established vivo microbiome, before spiking Coccidioides. Our data indicate respiratory microbiome species inhibit growth. depletion allows greater growth, disc diffusion treatments performed. suggests commensals Antibiotic may kill creates niche for invasion. Supported by grant VFR-19-633952 from University California Office President.