Medanta Chairman Dr Naresh Trehan on May 21 informed that the key to controlling black fungus is the judicious use of steroids and good control of diabetes. Dr Trehan said, “The key to controlling black fungus is the judicious use of steroids and good control of diabetes.” “The first symptoms of COVID-associated Mucormycosis are pain/stuffiness in the nose, inflammation on cheek, fungus patch inside the mouth, swelling in the eyelid etc. It requires aggressive medical treatment,” he added.