Although detailed case series have not reported on antibiotic use among patients, broad-spectrum antibiotics are presumed to be used in 75% of COVID-19 patients admitted to ICU [49]. Since the human gut microbiome is a highly complicated structure of bacteria and fungi, although bacteria are the most diverse constituents, the administration of antibiotics results in perturbation of microbiome steady-state composition, which allows fungi to thrive, and may predispose the host to invasive fungal infections once the immune system becomes impaired [65,66].