What to Know About Black Fungus Disease

Black fungus disease, or mucormycosis, is a rare infection that develops after someone inhales or touches spores (reproductive cells in plants) from a type of mold known as mucromycetes. People with a weakened immune system and those who have recently recovered from COVID-19 are more susceptible to this illness.

This article will explore what black fungus disease is, the symptoms you can expect, treatment options, and its link to COVID-19.

black mold mask covid

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Facts and Myths About Black Fungus

Black mold is dangerous to human health. Many molds can take on green, dark, or black colors, but few are deadly. Mucormycosis is called black fungus not because of the color of the fungus itself but because it can make the skin turn black in infected areas.

Exposure

Black fungus disease can develop anywhere that mucormycetes fungi grow. They are found worldwide, commonly in wet, moist, or humid areas. People who work in close contact with dirt and soil, like construction workers or gardeners, are at a greater risk of exposure.

Transmission

Mucormycosis infections develop from inhaling spores of the mucormycetes fungi or when these spores enter the skin through a cut or open wound. They do not spread from person to person or between people and animals.

Global Black Fungus Statistics

While the fungi that cause mucormycosis infections can grow just about anywhere, more attention is given to these molds when many people report infections.

Generally, people who develop black fungus disease are those with a compromised immune system or are living with certain chronic diseases. There have been notable outbreaks, especially during the COVID-19 pandemic.

India

India has rates of black fungus disease 80 times higher than developed countries. According to the World Health Organization, the global prevalence of mucormycosis infections is about 0.005 to 1.7 per 1 million people, but in India, that increases to roughly 140 per 1 million people.

United States

There is no national tracking program for mucormycosis infections in the United States because they are so rare. The national prevalence is approximately 1.7 cases per 1 million people. Large-scale outbreaks are linked to traumatic injuries during natural disasters.

While this infection isn't common in the United States, it is serious. About 54% of all cases are fatal.

 Symptoms

Symptoms of a black fungus disease depend on the body part most impacted. Mucormycosis is usually named for where symptoms occur in the body.

Sinus and Brain

Rhinocerebral mucormycosis affects the sinus cavities and brain. Symptoms can include:

  • Swelling on one side of the face
  • Headache
  • Fever
  • Black sores or lesions in or on the nose or mouth

Lungs

Pulmonary mucormycosis affects the lungs. Symptoms include:

Skin

Cutaneous mucormycosis affects the skin. The skin can become warm or you can develop:

Gastrointestinal System

Gastrointestinal mucormycosis affects the stomach, intestines, or another part of the digestive tract. Symptoms include:

Disseminated Mucormycosis

Disseminated (spread through an organ of the body) mucormycosis occurs in people with other health conditions. It is difficult to distinguish which symptoms are caused by mucormycosis and which are caused by other health issues.

Causes and Risk Factors

People who live or work in wet areas are at an increased risk of exposure to mucormycetes since it naturally occurs in the dirt and throughout our environment.

Most people who come into contact with this fungus do not get sick. Those who get sick tend to have other health conditions that increase their risk of infection.

Some of these risk factors include:

  • Diabetes
  • Cancer
  • History of an organ or stem cell transplant
  • Neutropenia (low white blood cells)
  • Long-term corticosteroid use
  • Suppressed immune system
  • Use of intravenous (IV) drugs
  • Hemochromatosis (too much iron in the body)
  • Skin injuries or wounds
  • Prematurity or low birth weight

When to See a Healthcare Provider

If you've been in an area where you may have been in contact with contaminated soil, talk to your healthcare provider. You may need testing if you had open wounds or develop symptoms of an infection.

Most of the symptoms of black fungus disease, like fever and chest pain, can develop with a number of other infections. See your healthcare provider if you experience any symptoms that don't improve or resolve.

Diagnostic Tests

A diagnosis of black fungus disease requires examination of infected tissue under a microscope (histopathology) or positive fungal culture of bodily fluid. Your provider may take a wound sample or use a blood or mucus sample for testing.

Treatment and Surgery

Early diagnosis and treatment are essential to positive outcomes with a mucormycosis infection. Infections are treated with antifungal medications that slow or stop the growth of fungi.

Your healthcare provider may try to treat the infection by improving any underlying health conditions putting you at increased risk. They may recommend surgery to remove damaged tissue for black fungus disease affecting the sinus, brain, skin, and gastrointestinal system.

Link Between COVID-19 and Black Fungus

Black fungus infections have been linked to COVID-19 and are referred to as COVID-19-associated mucormycosis (CAM). One study explored the link between COVID-19 and black fungus infections and found more than 47,000 cases of CAM over three months in India.

Before the COVID-19 pandemic, India recorded higher numbers of mucormycosis infections than other parts of the world. This likely is due to the nation's high rates of undiagnosed or uncontrolled diabetes and a lack of healthcare access.

Another study suggests that corticosteroids to treat severe COVID-19 infections may increase the risk of developing a mucormycosis infection. Most participants in the study developed mucormycosis about two weeks into their hospital stay for COVID-19; a few weren't diagnosed until after they died.

People With Diabetes

Type 2 diabetes can lead to health complications, including CAM. A 2021 report noted uncontrolled diabetes as the top risk factor for mucormycosis infections in COVID-19 patients in India, followed by corticosteroid use and extended stays in critical care units.

Strengthening Immune Function

The best way to keep your immune system strong is to adopt healthy habits like eating a balanced diet, getting regular exercise and sleep, and avoiding smoking or heavy drug and alcohol use.

Preventing Black Fungus

Keeping the areas where you live and work clean and dry is important for preventing infections, including mucormycosis. However, it may not be possible to avoid these fungi altogether.

You can reduce your risk of developing mucormycosis by maintaining your health and getting vaccinated against COVID-19 and other infections that can increase your risk of developing mucormycosis.

Summary

Black fungus disease is a rare but dangerous fungal infection associated with severe and deadly symptoms. Diabetes and other illnesses, like COVID-19, can increase your risk of developing this fungal infection. Talk to your healthcare provider if your immune system is weakened or you have a condition that could put you at risk of this disease.

A Word From Verywell

Most people exposed to the fungus that causes black fungal disease (mucormycetes) do not develop the illness. However, people with a weakened immune system are at a greater risk for infection when exposed. Although this disease can be life-threatening, there are treatments available. Maintaining your health can reduce your risk of developing this rare disease.

Frequently Asked Questions

  • Is mucormycosis the same as black toenail fungus?

    There are many types of fungus, but toenail fungus and the fungus that causes mucormycosis aren't the same. Mucormycosis can cause skin symptoms, but your provider would need a sample of the infected tissue to make an accurate diagnosis.

  • Why does COVID-19 cause fungal infections?

    COVID-19 doesn't cause fungal infections, but it weakens your body, allowing fungal infections to grow. Medications like corticosteroids used to treat severe COVID-19 can suppress your immune system and increase the risk of developing a fungal infection.

  • What’s the difference between mucormycosis and edible black fungus mushrooms?

    The fungus that causes mucormycosis develops in small spores that can be inhaled or enter through your skin, as opposed to growing as mushrooms with stems and caps. Be sure you know what kind of mushroom you have before eating it.

  • Is black fungus contagious?

    Mucormycosis infections can't be transmitted from one person to another or between animals and people. You must have direct contact with the fungus that causes this infection.


16 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Rachael Zimlich, BSN, RN
 Rachael is a freelance healthcare writer and critical care nurse based near Cleveland, Ohio.