COVID-19 Coronavirus: Is Infection along with Mycoplasma or Other Bacteria Linked to Progression to a Lethal Outcome?
Since we prepared this manuscript, there have been recent contributions, mostly brief preprint reports or letters that support our hypothesis. Charkraborty and Das  discussed the possibility that anaerobic bacteria, including Mycoplasma species, could be causing secondary infections in COVID-19 disease. They have proposed that such infections may be altering hemoglobin degradation and producing metabolites that affect hypoxia in progressing COVID-19 patients . Stricker and Fesler  suggested that patients who have COVID-19 disease should not progress to a fatal outcome, if their therapy includes combinations of antibiotics (including minocycline or doxycycline) used for tick-borne infections . As we discussed previously, Lyme disease patients often have mycoplasma co-infections that are sensitive to minocycline and doxycycline  .