Why is the black fungus killing patients with COVID in India?
Mucormycosis, aka black fungus symptoms, diagnosis, treatment, and prevention are explained in this video.
Black fungus / Mucormycosis is a rare but dangerous infection. It’s caused by a group of molds known as Mucormycetes. These fungi can be found in decaying leaves, compost piles, and rotten wood. Molds require moisture and decaying organic (living) material to thrive. Mucormycetes release large numbers of spores that can go into the air. Infections occur more frequently in the summer and fall than in the winter and spring.
Black Fungus in COVID Patients
People can inhale fungal spores when they are near moist dead vegetation. Small hair-like structures called cilia can catch these spores in your airways and get into your lungs. If your immune system is weak or your cilia don’t work well, it is easier for the spores to get deep into the sinuses or other body tissues. Besides entering your body through your mouth, nose, and sinuses, the black fungus can also enter through a break in your skin, such as a cut or scrape.
What types of infection can mucormycosis cause?
The types of black fungus infections depend on where they enter your body:
Rhinocerebral mucormycosis is an infection of the sinuses that can occur when a person with a weakened immune system breathes in the fungal spores. Air enters the nose and may go into the sinuses, air chambers found in the facial bones. Sinuses are air pockets that serve to lighten the skull, provide resonance for speech, and moisturize and warm the air we breathe.
The infection can spread from the sinuses to the brain or the eyes. For example, people with diabetes who have poorly controlled blood sugar are more likely to develop a black fungal infection of the sinuses. Same for those who have had a kidney transplant.
Lung mucormycosis is most common in those with a very weakened immune system after having cancer treatment or an organ transplant.
Skin mucormycosis develops when the fungus enters the skin through a scrape or cut in the skin. This is the most common type of black fungus infection in people who have a healthy immune system.
Disseminated mucormycosis occurs when the infection spreads throughout the body via the bloodstream. The fungus invades the blood vessels, reducing blood flow to organs and tissues supplied by these damaged blood vessels. When blood flow is decreased, tissues cannot get oxygen and nutrients and start to die. Dying tissue turns black. Black fungus grows well on dying tissue. After passing through the blood, the fungus usually affects the brain, but it can also affect the spleen, heart, and skin.
How is mucormycosis associated with COVID?
An opportunistic infection takes advantage of you when your immune system is weak. So we use steroids like dexamethasone, aka decadron, to treat sicker people with COVID. When COVID gets into the lungs, meaning COVID pneumonia, the immune system is stirring up a crazy amount of inflammation there, which can do a lot of damage. So we try to minimize that inflammation with steroids. Sometimes, for very severe COVID pneumonia, we also give a drug called Tocilizumab, which also makes the immune system weaker.
Unfortunately, this can lead to black fungus infection. Not just because it suppresses the immune system. But also because steroids increase blood sugar levels. And fungal infections love sugar. Sugar is their go-to for nutrition. People with uncontrolled diabetes have higher blood sugar levels which help the fungus grow and flourish. Diabetes is extremely common in India. It is estimated that 15% of adults in India’s urban areas have it.
So why is this happening mainly in India?
One reason is related to the swelling number of COVID cases, in addition to the liberal use of steroids there. But there are likely other factors as well. For example, sometimes, there are mucormycosis outbreaks in hospital settings.
Doctor Mike Hansen, MD
Internal Medicine | Pulmonary Disease | Critical Care Medicine