Microbial detection in COVID-19 patients. (A) Box plot showing the expression levels (RPMs) of human mastadenovirus C, Klebsiella pneumoniae, Candida glabrata, and Toxoplasma gondii in healthy donors and COVID-19 patients. Each point represents the mean value of the RPM of a patient/healthy volunteer at all time points. (B–E) The IGV view showing cfRNA reads mapped to human mastadenovirus C genome (B), Klebsiella pneumoniae genome (C), Candida glabrata genome (D), and Toxoplasma gondii genome (E) in healthy donors and COVID-19 patients. (COV) All COVID-19 patients (including mild and severe COVID-19 patients), (control) all healthy donors. Asterisks indicate statistically significant differences; (***) P < 0.001.