In this devastating 2nd wave of COVID-19, a new challenge in the form of ‘Black fungus’ (or Mucormycosis) is maiming people with COVID-19. A lot of myths and rumors have also been doing rounds around this fungal infection. Here, we aim to bring scientific facts ONLY to help you understand this notorious pathogen and stay protected.
An Insight Into Mucormycosis: Know The Basics
Mucormycosis, colloquially known as Black Fungus, is a rare but serious fungal infection caused by a group of fungi called ‘mucor’ . This fungus has always been part of our environment. It is normally found indoors and outdoors alike, including soil, plants, decaying fruits, and vegetables. Spores from these fungi are breathed in by humans daily and are mostly harmless.
However, this fungus is an opportunistic pathogen, which implies that it takes advantage of a particular situation and causes the illness. Factors such as weak immunity, frequent use of immunosuppressive medicines, and comorbidities such as uncontrolled diabetes create a hostile environment for the growth of this opportunistic fungus . The raid of COVID-19 has affected the immune system to a great extent, making individuals vulnerable to this otherwise harmless fungal infection.
Unlike COVID-19, mucormycosis is not contagious. That is, it does not spread from person to person. Early detection and timely treatment can act as key elements in fighting this rapidly progressing, life-threatening infection. Its treatment usually consists of antifungal medications with or without surgery .
Mucormycosis OR ‘Black Fungus’: Are They The Same?
Mucormycosis in COVID times is colloquially called ‘Black fungus’. We discussed with two experienced doctors as to what might have led to this misnomer. There could be two reasons. First, this term got associated with mucormycosis due to the presence of black dots among the culture of white fungal colonies. Or, this is probably due to the blackish-bluish discoloration of the affected damaged tissues .
However, black fungus is an altogether different species of fungi that comprises pigment in their cell walls. Due to the pigmentation, they appear dark green, brown, or black and hence the name .
It would be appropriate to say that the fungal infection that has recently been affecting COVID-19 patients is Mucormycosis and not the black fungus! . It can complicate the course of the coronavirus infection and hence is interchangeably called COVID-19 associated Mucormycosis (CAM) . The color-coding of fungal infections could be misleading and can create ambiguity in the treatment, and hence we should know the fungi by their names, and not by their color .
Mucormycosis: Not Much Of A New Disease!
Undoubtedly, mucormycosis may have come into the limelight recently after the second wave of COVID-19, but its existence can be dated in the pre-COVID times as well. It was known to occur in people with weak immune systems, having diabetes, taking immunosuppressive medicines, and undergoing cancer chemotherapy .
Some cases of this aggressive fungal infection had also been observed during the 2003 SARS pandemic.
Types of Mucormycosis
Mucormycosis can be classified into five types. These categories are based on the parts of the body that this disease affects  :
1. Rhino-orbito-cerebral Mucormycosis: It affects the nose, sinus, eye, and brain. It is commonly seen in COVID-19 patients with uncontrolled diabetes and in individuals who have had an organ transplant.
2. Pulmonary Mucormycosis: It affects the lungs. It is commonly seen in individuals with cancer or who have had an organ transplant.
3. Gastrointestinal Mucormycosis: It mainly affects the stomach and intestines. It is commonly seen in young infants and individuals who have had antibiotics or other medications that lower the body’s ability to fight infection. It can also affect individuals who have had surgery.
4. Cutaneous Mucormycosis: It affects the skin and can occur after a burn, cut, or any other skin injury. It is commonly seen in individuals with blood cancer, uncontrolled diabetes, HIV, and intravenous drug use.
5. Disseminated Mucormycosis: This type of infection is seen in people who are already sick from other medical conditions. This occurs when the infection has spread to multiple organs via blood.
Who Is At A Higher Risk Of Getting Mucormycosis?
Mucormycosis can be contracted by people of any age group, including children, adults, and the elderly. However, elderly people with low immunity and underlying comorbidities like uncontrolled diabetes are more prone to develop this fungal infection. Children with insulin-dependent diabetes are at risk as well .
COVID-19 and Mucormycosis
Under normal conditions, our body’s immune system successfully fights fungal infections such as mucormycosis. But these are not normal times, the advent of COVID-19 in our lives has affected the immunity of the COVID-affected individuals. COVID-19 infection causes a decrease in white blood cells (WBCs), our body’s defense system. These WBCs help the body fight infections and their scarcity makes our immunity weak. To add to that, the use of certain medicines such as steroids and tocilizumab as a part of COVID-19 treatment further compromises immunity .
COVID-19 affected diabetics are also at a greater risk of developing mucormycosis, especially if their diabetes is poorly controlled. Though the exact cause is unknown, it is believed to be due to the glucose overload in the tissues that provides a favorable environment for the growth of mold fungi . As per some studies, excess iron or an acidic environment in the body can also promote fungal growth.
Do not panic! Not all people with COVID catch mucormycosis.
Nowadays, there is a buzz going around saying the probability of getting infected from Mucor is high in the COVID-19 recovered patients. However, not all COVID patients get infected with it. High-risk groups include COVID-19 positive people with either or all of the following conditions: [8,9]
– Uncontrolled diabetes
– Took high-dose steroids therapy
– Underwent immunomodulatory therapy like tocilizumab, baricitinib, etc.
– Had long stay in ICU
No definite link between oxygen therapy and mucormycosis
As per the Fungal Infection Study Forum Recommendation for COVID-19 associated mucormycosis, it is not spread by oxygenation, humidifier, and water. Dr. Randeep Guleria, AIIMS Chief, has also apprised in the media briefing held on May 24, 2021, that many people taking treatment at home, who were not on oxygen therapy, have also been found to get infected with it.
Symptoms of Black Fungus Mucormycosis
COVID-associated mucormycosis generally starts in the nose and if not taken care of early may progress to the eyes and brain .
Symptoms can depend on the area where the infection is growing. Here is a list of commonly observed symptoms and an overview of the intensity of the spread at each phase.
1. Relatively Early Phase (nose and sinus involvement)
-Blocked nose or nasal discharge
-Sinus pain or headache (persistent or severe ache that does not respond to pain-relieving medicines)
-Facial pain, numbness, or swelling
-Bluish-black discoloration of the facial skin
-Loosening and discoloration of teeth or development of ulcers on the roof of the mouth
2. Moderately Advanced Phase (eye involvement)
-Pain, swelling, or redness in the eyes
-Loss of vision
3. Severe Phase (brain involvement)
-Cranial nerve paralysis (decreased function of nerves coming from brain)
-Altered mental status
-Deficits in movement
-Impaired speech ability
If you are recovering or have recovered from COVID-19 and noticed any of the above symptoms, consult a doctor IMMEDIATELY. Early diagnosis and treatment can reduce complications and offer better support.
Tests for Black Fungus Mucormycosis
Your doctor will identify this fungal infection based on your medical history and thorough clinical evaluation. If needed, a swab from the nose may be required to test the presence of fungus. Other specialized tests including biopsy and CT scan might also be required in some people [7,10].
Quick Tips To Prevent Mucormycosis
Some of the common tips recommended include[4,9,10]:
-Use masks if you are visiting dusty con
-People with COVID-19 who are diabetic, or had a prolonged stay in ICU should track and control blood sugar levels post discharge
-Never self-medicate, especially steroids
-Watch for symptoms and do not lose any time in starting treatment
-Follow your doctor’s instructions on seeking advanced investigations like biopsy or CT scan
-Masking can reduce exposure to mucor in the environment. Find the perfect mask here and stay protected from infections.
-Wear shoes, long trousers, long sleeve shirts, and gloves while handling soil (gardening), moss, or manure. Avoid gardening if you are diabetic and your immunity is weak due to any reason.
-Maintain personal hygiene and basic sanitation
-Ensure proper ventilation and let sunlight enter your homes.
-People at risk should avoid visiting damp places soon after recovery from COVID.
Could There Be A Lifetime Risk Of Getting Mucormycosis After COVID-19?
As per experts, while most people contracted it between 2-3 weeks after recovery from COVID-19, there could be a higher risk of mucormycosis within 6 weeks of COVID treatment. The data available is not sufficient enough to draw any conclusion.
Can Mucormycosis Be Treated?
It is a medical emergency even when clinically suspected. The treatment of this condition requires a dedicated multidisciplinary team approach to control any further spread of the infection .
The treatment process includes [7,11]:
Early detection and immediate action
1. Antifungal Therapy
Antifungal medicines such as Liposomal Amphotericin B, Posaconazole, and Isavuconazole may be given through a vein (intravenous or IV) or as oral tablets for several weeks.
Amphotericin B is often used as the first-line treatment. Renal function and potassium levels are usually monitored while administering amphotericin B. After 3-6 weeks of amphotericin B therapy initiation, consolidation therapy is started either with posaconazole or isavuconazole to prevent any relapse.
For patients who are intolerant to amphotericin B, alternative medicines can be given such as posaconazole or isavuconazole (injection/tablets).
2. Endoscopic Surgery
In severe cases, particularly for rhinocerebral, cutaneous, and gastrointestinal types of fungal infection, a surgical method for the removal of infected tissue may be required in addition to medicinal treatment. Patients may need to be continuously monitored clinically with radio-imaging for response/disease progression.
Word of advice
Mucormycosis is a rapidly progressing infection that can cause high mortality rates, ranging from 40% to 80% . Do not ignore symptoms, trust your doctor and seek early treatment.
Links to all e-books: https://www.1mg.com/coronavirus-covid19
1. CDC. Mucormycosis. https://www.cdc.gov/fungal/diseases/mucormycosis/index.html
2. National Organization for Rare Disorders. Mucormycosis. https://rarediseases.org/rare-diseases/mucormycosis/
3. CDC. About Mucormycosis. https://www.cdc.gov/fungal/diseases/mucormycosis/definition.html
4. Youtube. “Persistent Headache, Swelling Signs Of Black Fungus”: AIIMS Chief. https://www.ndtv.com/video/news/fighting-covid-19-in-conversation-with-dr-randeep-guleria/black-fungus-symptoms-persistent-headache-swelling-signs-of-black-fungus-aiims-chief-587241
5. Lin L and Xu J. Fungal Pigments and Their Roles Associated with Human Health. J Fungi 2020, 6(4), 280. https://pubmed.ncbi.nlm.nih.gov/33198121/
6. Labelling the same fungus with names of different colours can create confusion: Randeep Guleria, AIIMS director. https://economictimes.indiatimes.com/industry/healthcare/biotech/healthcare/labelling-the-same-fungus-with-names-of-different-colours-can-create-confusion-randeep-guleria-aiims-director/videoshow/82910948.cms
7. Fungal Infection Study Forum (FISF). COVID19-associated mucormycosis (CAM). https://www.dgho.de/arbeitskreise/i-k/infektionen/aktuelles/fish-recommendation-mucormycosis.pdf
8. PIB. Stay Safe from Mucormycosis – a Fungal Complication being Detected in COVID-19 Patients Control Diabetes, Use Steroids Judiciously, Keep Good Hygiene, Don’t Self-Medicate. https://pib.gov.in/PressReleseDetailm.aspx?PRID=1718501
9. ICMR. Evidence-based Advisory in the time of COVID-19 (Screening, Diagnosis & Management of Mucormycosis). https://www.icmr.gov.in/pdf/covid/techdoc/Mucormycosis_ADVISORY_FROM_ICMR_In_COVID19_time.pdf
10. AIIMS COVID Portal. https://covid.aiims.edu/mucormycosis-in-covid-19/
11. NIH. Endoscopic Surgical Treatment of Rhino-Sinusal Mucormycosis (MICCA). https://clinicaltrials.gov/ct2/show/NCT02226705
12. Oliver A Cornely OA, Alastruey-Izquierdo A, Arenz D, et al. Global guideline for the diagnosis and management of mucormycosis: an initiative of the European Confederation of Medical Mycology in cooperation with the Mycoses Study Group Education and Research Consortium. Lancet. VOLUME 19, ISSUE 12, E405-E421, DECEMBER 01, 2019. https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(19)30312-3/fulltext