Hyderabad: Doctors say severe oxidative stress inside infected tissues was a key reason why black fungus disease (mucormycosis), which surged during COVID-19, caused rapid and widespread tissue destruction. Oxidative stress is a condition where harmful molecules called free radicals overwhelm the body’s natural defences and damage cells.Black fungus is a rare but deadly fungal infection that mainly affects people with weak immunity. India saw a sharp rise in cases in 2021, largely because many COVID-19 patients had uncontrolled diabetes and were treated with steroids.The most dangerous form begins in the sinuses and can quickly spread to the eyes and brain. Once the brain is affected, the risk of death can rise to 80%. In 2021, over 3,000 deaths in India were linked to COVID-related mucormycosis.In a study, doctors from LV Prasad Eye Institute (LVPEI), working with the University of Alabama in the US, examined eye and orbital tissues removed from 14 patients with severe infection, including 10 who had COVID-19. The samples were compared with healthy tissues. Around 93% of the patients had diabetes, highlighting a strong link between diabetes and the disease. COVID-19 viral proteins were found in 71% of the COVID-related cases, even in some patients who had recovered earlier. The study was published in the journal Medical Mycology.Doctors found extremely high oxidative stress in infected tissues, which damaged cells and triggered multiple cell-death processes, leading to rapid tissue destruction. These changes were seen in both COVID and non-COVID patients.“The findings show that while COVID-19, steroid use and diabetes increase the risk of infection, the severe tissue damage is mainly caused by the fungus itself. This could help develop treatments that not only kill the fungus but also reduce tissue damage and improve survival,” said Dr Sanhita Roy, head of ocular pharmacology research at LVPEI and author of the study.
