Indian doctors raised the alarm over a surge in cases of an extremely rare but deadly fungal infection affecting recovered Covid-19 patients. The mortality rate of those infected is estimated to be more than 50 per cent. At least 41 cases of what doctors are calling Covid-19-triggered mucormycosis were detected in Delhi and the western city of Ahmedabad, about 20 of them in December, hospital authorities say. There is growing concern over the use of cortisol steroids, commonly<strong> </strong>used around the world for Covid-19 patients to suppress the immune system. New Delhi’s Sir Ganga Ram hospital said 13 patients were admitted in the past 15 days, with five losing their eyesight or nose and jawbones, while five died. There were warnings of a possible rise in cases in the coming weeks. Before December, there were only five fungal infection cases that doctors think may have been linked to Covid-19. "We are continuously having more patients," Dr Manish Munjal, senior ENT surgeon at Delhi's Sir Ganga Ram Hospital, told <em>The National.</em> “By tomorrow maybe the count could be 20. We are seeing a trickle of one to two cases every day and in the next 10 to 12 days we see a possibility of more cases.” Mucormycosis, or black fungus, is caused by mucormycetes – fungal spores that are naturally present in soil and air. These can enter the human body through the respiratory tract, sinuses or skin. Although these fungi do not cause harm to most people, those with weak immune systems are highly vulnerable. If an infection gets out of control, the fungi invade tissue cells and can damage the gastrointestinal and respiratory tracts, sinuses and brain, leading to horrific symptoms including severe haemorrhaging. Experts say weakened immunity, lung damage and use of steroids for treating Covid-19 disease leaves recovered patients vulnerable to mucormycosis infection. The current wave of infections is showing a high prevalence among the elderly, those with diabetes and those whose immune systems are compromised. Doctors are linking the rise in infections to the widespread use of cortisol steroids to treat an excessive immune response in severe Covid-19 patients, known as a cytokine storm. While the body’s immune response can be deadly, suppressing it is not without cost. “Patients recover from Covid infections and go home, but the body is still too weak to counter other sorts of infections and one of the most dangerous ones is mucormycosis,” Dr Munjal said. “Due to this steroid treatment the Covid and the symptoms improve, but at the same time the body starts to get immune deficiency over a period of a week or two weeks. “Because this condition has a high mortality rate, above 50 per cent, it requires very early detection and aggressive management.” Experts said initial symptoms included persistent nose infection, facial numbness and fever. Many patients develop black lesions and grotesque injuries in infected areas including eyes, nasal and jaw bones, and the brain. Because of this risk, Indian doctors now face a dilemma. “We cannot do without steroids. That has to be given. However, when we have a vulnerable post transplant patient or diabetics, the immune system is already compromised. These are typically the patients who have lung complications because of Covid and are given higher doses of steroids,” said Dr Varun Rai, consultant ENT surgeon at Sir Ganga Ram Hospital. “Our aim of highlighting this is that a physician should also be on the lookout for these subtle signs where a patient may be at a risk of developing fungal infection. It is part awareness for the general population as well as the medical fraternity,” he said. One problem, said Dr Rai, is that once the infection takes hold, it can be incredibly hard to treat. The main treatment, Amphotericin B therapy, can itself be dangerous in large quantities. “Once there is a fungal infection, surgery is used for reducing the fungal load and the main treatment is Amphotericin B. “But the medicine affects the kidneys as well so can't be given a high dose otherwise kidneys are going to be shut down,” Dr Rai said. India has had 9.9 million confirmed cases of coronavirus and nearly 144,000 have died, a toll second only to that of the US. At least 9.4 million Covid-19 patients have recovered from the viral disease. But the latest fungal infection raises safety concerns for millions of them. "This fungus is not uncommon in Indian patients, mostly those suffering from diabetes, but we are witnessing a roughly fivefold spike due to the pandemic," said Dr Atul Patel, a director at the Vedanta Institute of Medical Sciences Ahmedabad<em>.</em> Dr Patel’s infectious diseases centre received 19 cases in the past three months, more than half of them in the past 15 days. “All of them remain under treatment that will likely last three to six months,” he said. “Some of them have damage to their eyes, jaws, kidneys, lungs, and one patient died.” Dr Patel said the patients were in a life-threatening condition until they were completely free of the fungus. Doctors say that increased testing for diagnosing fungal and bacterial co-infections in vulnerable Covid-19 patients should be undertaken to ensure better early management of the deadly infection. There is no explanation as to how so many Covid-19 patients in India have contracted the fungal infection. But doctors suspect that most of the cases were clustered, pointing towards a common source of infection, including the hospital environment. Dr Patel said a nationwide study between April 2016 and September 2017 found 474 cases of the rare infection, with a mortality rate of 52 per cent, which he believed would increase because of Covid-19. Most patients died within six weeks of infection, Dr Patel said. There is no India-specific or global data available on the fungal infection, but studies by the US Centres for Disease Control suggest a mucormycosis prevalence rate of 1.7 cases for every million people. The fungal infection is mostly found in transplant centres, the US authority said.