Government has told doctors to look out for signs of mucormycosis or "black fungus" in Covid-19 patients. This comes as hospitals report a rise in cases of the rare but potentially fatal infection. Indian Council of Medical Research (ICMR) said at the weekend that doctors treating Covid-19 patients, diabetics & those with compromised immune systems should watch for early symptoms. The symptoms include sinus pain or nasal blockage on one side of the face, one-sided headache, swelling or numbness, toothache & loosening of teeth. The disease, which can lead to blackening or discolouration over the nose, blurred or double vision, chest pain, breathing difficulties & coughing blood, is strongly linked to diabetes. Covid-19 patients more susceptible to contracting the fungal infection include those who used steroids during their virus treatment & those who had prolonged stays in hospital ICUs, the ICMR added. Media reports have pointed to cases in Maharashtra & state capital Mumbai, and Gujarat. Watch the video to know more.