What is Black Fungus in the Eye?
Medically known as mucormycosis, black fungus in the eye is a serious condition that can cause permanent vision loss or even require removal of the eye if not caught and treated in time.
Understanding Black Fungus in the Eye
When black fungus enters the body, it usually starts in the nose and sinuses. From there, it can travel into the eye socket and then onward to the brain. This is why the most common form seen in India is called rhino-orbital-cerebral mucormycosis, a name that simply means the infection starts at the nose, moves to the eye socket, and can reach the brain.
The fungus works by blocking and destroying the small blood vessels in the area it infects. When blood supply is cut off, the tissue dies. Dead tissue turns black, which is exactly where the name “black fungus” comes from. On the nose, the skin or inner lining may turn dark. Around the eye, the tissue may appear bruised or discoloured. This is a visible and urgent warning sign.
India has carried a significantly higher burden of this infection than most other countries, even before COVID-19. Studies estimate that mucormycosis rates in India were approximately 70 times higher than the global average before the pandemic, largely because of the country’s very high rate of diabetes. During the second COVID-19 wave in 2021, the combination of COVID-19, steroid treatment, and uncontrolled diabetes created an enormous surge. Over 40,000 confirmed cases were reported in India by June 2021, and several states declared it an epidemic.
What are the Black Fungus Symptoms?
The black fungus symptoms come on quickly and worsen fast. This is not a condition where waiting a few days to see how things develop is safe. If you or someone in your family has recently recovered from COVID-19, has diabetes, or has been on steroids for any condition, and any of the following black fungus symptoms appear, please seek medical attention the same day. Do not delay.
Early Black Fungus Symptoms (Face and Nose)
These are usually the first black fungus symptoms to appear:
Icon | Symptom | What to notice |
🤧 | One-sided nasal blockage | Stuffiness in one nostril, often with dark or blood-stained discharge |
🖤 | Dark discolouration | Blackening or dark patches on the skin of the nose or the roof of the mouth |
😖 | Facial pain or numbness | A dull ache, pressure, or strange numbness across the cheeks or forehead |
🤕 | Worsening headache | Persistent headache that does not improve with standard pain relief |
🌡️ | Fever | Unexplained fever, particularly after recovering from COVID-19 or a hospital stay |
🦷 | Pain in the teeth or jaw | Loosening of teeth or jaw pain without any dental cause |
Black Fungus Infection Symptoms in the Eyes
If the infection has moved from the sinuses into the eye area, these black fungus infection symptoms in eyes appear:
Icon | Symptom | What it means |
👁️ | Swollen or puffy eyelid | The infection is spreading into the soft tissue around the eye |
🔴 | Redness around the eye | Inflammation as the infection reaches the eye socket |
😵 | Blurred or double vision | The eye muscles and nerves are being affected |
😰 | Pain in or around the eye | Pressure building up inside the eye socket |
😶 | Drooping eyelid | Nerve damage or compression from the spreading infection |
👁️🗨️ | The eye pushing forward | The infection is building up pressure behind the eye |
🌑 | Partial or complete vision loss | The optic nerve or blood vessels supplying the eye are involved |
When is This an Emergency?
The following combinations should be treated as a medical emergency. Go to hospital immediately if someone with diabetes, a weakened immune system, or recent COVID-19 history develops:
- Swelling around one eye alongside any nasal or facial symptoms
- Any sudden change in vision alongside headache or fever
- A drooping eyelid appearing suddenly with no obvious cause
- Dark or black discolouration appearing on the nose, cheek, or inside the mouth
- Eye redness and pain that appeared after a hospital stay or COVID-19 recovery
Every hour without black fungus treatment allows the infection to spread further. The difference between catching it early and catching it late can be the difference between saving the eye and losing it.
What are the Black Fungus Types in the Eye?
Black fungus in the eye is almost always part of the rhino-orbital-cerebral form of the infection. However, doctors classify the different black fungus types based on which part of the body is primarily affected. Understanding these black fungus types helps explain why some patients have mainly facial and eye problems while others develop chest or skin symptoms.
The Main Black Fungus Types
Type | Where it affects | Most common in |
Rhino-orbital-cerebral | Nose, sinuses, eye socket, brain | Diabetic patients, COVID-19 survivors on steroids – most common in India |
Pulmonary (lung) | Lungs and airways | Cancer patients, organ transplant recipients |
Cutaneous (skin) | Skin at a wound, burn, or injection site | People with skin injuries or surgical wounds |
Gastrointestinal | Stomach and intestines | Premature newborns, severely malnourished individuals |
Disseminated | Spreads through blood to multiple organs | Severely immunocompromised patients, the most dangerous form |
The rhino-orbital-cerebral form is by far the most common type of black fungus seen in India, accounting for the large majority of cases reported during and after the COVID-19 period. The eye sits directly in the path of the infection as it moves from the sinuses toward the brain, which is why black fungus in the eye became such a significant concern.
What Causes Black Fungus in the Eye?
The black fungus causes are always a combination of two things happening together. First, the person is exposed to mucormycetes spores, which is unavoidable because these moulds exist in the soil and air around us every single day. Second, and more importantly, the person’s immune system is not strong enough to stop the infection from taking hold.
Understanding the black fungus causes helps identify who needs to be most careful and most alert to early symptoms.
Who Is Most at Risk?
Uncontrolled diabetes This is the single biggest risk factor for black fungus in India. High blood sugar weakens the white blood cells that are supposed to fight off fungal spores. In someone with poorly managed diabetes, the fungus finds little resistance and spreads quickly. Over 64% of India’s 2021 black fungus patients had diabetes, which tells you how central this risk factor is.
COVID-19 and steroid treatment COVID-19 itself suppresses the immune system. The steroids used to treat severe COVID-19 suppress it further. Many patients also had uncontrolled blood sugar during their illness. This combination created the conditions for black fungus to thrive. Most COVID-19-related black fungus cases appeared around 10 to 14 days after hospital discharge.
Other conditions that weaken immunity
- Cancer and chemotherapy
- Organ transplant recipients taking medicines to prevent organ rejection
- Prolonged use of steroids for any condition, such as asthma or joint diseases
- HIV/AIDS at advanced stages
- Severe kidney disease
Contaminated hospital equipment Some cases of black fungus in India were linked to contaminated medical oxygen, contaminated water used in humidifiers attached to oxygen cylinders, and unsterile wound dressings. Hospital hygiene plays a role in prevention.
High spore count environments Construction sites, areas with large amounts of soil disturbance, composting areas, and places with decaying organic matter have higher concentrations of mucormycetes spores in the air. Immunocompromised individuals should avoid such environments where possible.
Risk Factor Summary
Risk factor | Why it matters |
Uncontrolled diabetes | High sugar weakens the immune cells that fight fungal spores |
COVID-19 with steroid treatment | Double suppression of the immune system |
Cancer or chemotherapy | Immune system compromised by treatment |
Organ transplant | Anti-rejection medicines suppress immunity |
Long-term steroid use | Any steroid, not just COVID-related |
Contaminated hospital equipment | Oxygen humidifiers, wound dressings |
High spore environments | Construction dust, soil, composting areas |
How is Black Fungus Diagnosed?
Diagnosing black fungus quickly is critical because the infection spreads fast. Doctors do not always wait for all tests to come back before starting black fungus treatment. If the clinical picture strongly suggests the infection, treatment typically begins immediately.
Tests Used to Diagnose Black Fungus
Test | What it involves |
Clinical examination | The doctor examines the nose, mouth, skin, and eyes for the characteristic black discolouration, swelling, and other features |
Nasal swab and biopsy | A small tissue sample is taken from the nose or sinus and examined under a microscope to identify the fungal strands |
KOH mount | A quick staining test done on the sample that shows up the fungal elements under a microscope |
Fungal culture | The tissue sample is grown in a laboratory to confirm the exact species of fungus present |
CT scan (sinuses) | Shows the extent of sinus involvement and whether the infection has spread into the eye socket |
MRI scan (orbit and brain) | Used when the eye socket or brain involvement is suspected, to map exactly how far the infection has gone |
Blood tests | Checks blood sugar, kidney function, blood counts, and infection markers to understand the underlying condition |
What Does Black Fungus Treatment Look Like?
Black fungus treatment is intensive, aggressive, and often involves more than one specialist working together. Because the infection spreads quickly and can be fatal if not controlled, black fungus treatment is started as an emergency, not scheduled as a routine appointment.
The three pillars of black fungus treatment are: antifungal medicines, surgery to remove infected tissue, and controlling the underlying condition that allowed the infection to take hold.
Black Fungus Treatment Options
- Antifungal Medicines Tag: Started immediately The medicine of choice for black fungus treatment is Amphotericin B, given through an intravenous drip (IV) directly into a vein. This medicine is administered daily, often for several weeks. During India’s 2021 outbreak, the liposomal form (Liposomal Amphotericin B) was preferred because it works well and causes fewer side effects compared to the standard form. The drug was in significant short supply during the peak of the crisis, which highlighted just how important early prevention and diagnosis are.
If Amphotericin B cannot be tolerated, alternative antifungal medicines such as Posaconazole or Isavuconazole may be used. These are usually continued even after the initial IV course as oral maintenance black fungus treatment. - Surgical Removal of Infected Tissue Tag: Often essential Medicine alone is often not enough for black fungus. Because the fungus kills tissue and cuts off blood supply to the affected area, antibiotics and antifungals cannot always reach deep enough. Surgeons need to remove all the dead and infected tissue to stop the spread.
This is where black fungus treatment becomes difficult. In cases involving the nose and sinuses, this means clearing out the infected sinus tissue through an operation. When the infection has reached the eye socket, the surgery may involve removing the contents of the eye socket (orbital exenteration) to prevent the fungus from entering the brain. This is an extremely difficult outcome for patients and their families, but it can be life-saving. - Controlling Blood Sugar Tag: Critical for recovery Uncontrolled blood sugar is the environment in which black fungus thrives. Bringing blood sugar back under control is not just part of the underlying disease management, it is an active part of black fungus treatment. Without controlling diabetes, antifungal medicines have a much harder time working. All patients with black fungus who have diabetes need intensive blood sugar management alongside their antifungal treatment.
- Reducing or Stopping Steroids Tag: Where medically safe If the patient has been on steroids, reducing or stopping them as soon as medically safe is an important step. Steroids suppress the very immune response that the body needs to help fight the infection. The treating team will balance the need for steroids (for example, in a patient still dealing with severe COVID-19 lung disease) against the harm they are causing to black fungus recovery.
- Hyperbaric Oxygen Therapy Tag: Supportive, where available Some centres use hyperbaric oxygen therapy as a supportive part of black fungus treatment. High-pressure oxygen inhibits the growth of the fungus and supports tissue healing. This is not available everywhere but may be considered in severe or complex cases.
Black Fungus Treatment Overview
Treatment | Role | Given by |
Amphotericin B (IV) | Primary antifungal, kills the fungus | Given via drip in hospital |
Posaconazole / Isavuconazole | Alternative or follow-up antifungal | Oral or IV |
Surgical debridement | Removes dead and infected tissue | ENT or maxillofacial surgeon |
Orbital exenteration | Removes eye socket contents when eye is involved | Ophthalmologist, oculoplastic surgeon |
Blood sugar control | Removes the environment that lets the fungus thrive | Endocrinologist, treating physician |
Steroid reduction | Restores immune function | Treating physician |
Hyperbaric oxygen | Supportive healing | Specialised centres |
What are the Black Fungus Prevention Steps?
Black fungus prevention is focused on reducing the risk in people who are most vulnerable. For the general healthy population, normal hygiene and everyday precautions are enough. For people with diabetes, those on steroids, or those recovering from serious illness, black fungus prevention becomes an important and active responsibility.
Black Fungus Prevention for High-Risk Individuals
Control your blood sugar This is the single most important black fungus prevention step for anyone with diabetes. Well-controlled blood sugar means the immune system can function properly. If you are recovering from COVID-19 and have diabetes, monitor your sugar levels closely and follow your doctor’s advice on managing them during recovery.
Use steroids only as prescribed Steroids should only be taken when a doctor prescribes them, at the dose recommended, and for the duration specified. Taking steroids beyond what is prescribed, or using them without medical guidance, significantly increases black fungus risk.
Keep oxygen equipment clean During the COVID-19 period, many home oxygen setups had contaminated water in the humidifier attached to the cylinder. Always use sterile or clean water in oxygen humidifiers, and follow guidelines on cleaning the equipment. Contaminated humidifiers were identified as one of the routes through which spores entered patients’ airways.
Wear a mask in dusty or high-spore environments People who are immunocompromised should wear a well-fitted mask (N95 where possible) when near construction sites, soil-heavy areas, composting, or dusty environments where mucormycetes spore counts are higher.
Watch for early symptoms after COVID-19 recovery Black fungus symptoms can appear from a week to several weeks after recovering from COVID-19. If you have recovered from COVID-19 and develop any nasal, facial, or eye symptoms as described in the symptoms section, do not dismiss them. Report them to a doctor promptly.
Maintain good hygiene during and after hospitalisation During any hospital stay, particularly an ICU stay, good personal hygiene reduces infection risk. Wounds, surgical sites, and IV lines should be kept clean and changed as advised by healthcare staff.
Why India Has a Higher Burden of Black Fungus
India’s disproportionately high rate of mucormycosis compared to other countries comes down to several overlapping factors:
Diabetes prevalence India has one of the largest diabetic populations in the world, with over 77 million people living with diabetes as of recent estimates. Poorly controlled diabetes is the most consistent risk factor for black fungus across all studies. In a country where a significant proportion of diabetic patients do not have their blood sugar well managed, the underlying vulnerability to this infection remains high.
High environmental spore count The Indian climate, particularly the warm, humid conditions prevalent across large parts of the country, supports higher concentrations of mucormycetes in the environment. Studies have found outdoor spore counts of 800 to 4,800 spores per cubic metre in India, compared to 80 to 280 inside homes, meaning that exposure levels for high-risk individuals are significant.
Steroid misuse Self-medication with steroids, purchasing steroid tablets over the counter without prescription, is a known problem in India. Steroids suppress immunity and raise blood sugar levels, both of which feed directly into black fungus risk.
Awareness and diagnostic gaps Before the 2021 outbreak, many doctors outside of major cities had limited experience diagnosing and managing mucormycosis. This led to delays in recognition and treatment. The 2021 experience significantly raised awareness among doctors across India, which is itself one of the lasting benefits of that difficult period.
Black Fungus in the Eye: What Happened in India in 2021
During the COVID-19 second wave, India faced an unprecedented surge in black fungus cases. News reports from Mumbai, Delhi, Pune, Hyderabad, and across South India described patients who had survived COVID-19 only to be readmitted weeks later with facial swelling, black discolouration on their nose, and rapidly worsening vision in one eye.
For many of these patients, the infection had already reached the eye socket by the time they arrived at hospital. Surgeons faced the agonising task of removing eyes and in some cases clearing out entire eye sockets to save the patient’s life. In the worst cases, the infection had already reached the brain.
The outbreak placed enormous pressure on the supply of Amphotericin B across India. Hospitals in smaller cities often could not access the medicine. Families travelled long distances trying to procure injections for loved ones.
Several lessons came from this experience:
- Blood sugar must be controlled carefully in any patient receiving steroids for COVID-19 or any other condition
- Any new nasal, facial, or eye symptom appearing in a recently recovered COVID-19 patient should be investigated for black fungus as a priority
- Oxygen humidifier hygiene in hospital and home settings matters
- Early treatment, even before confirmation, saves lives and eyesight
Black Fungus Medicine for Eyes: What Doctors Prescribe
When black fungus has reached the eye area, the approach to black fungus medicine for eyes combines systemic antifungal treatment (medicines given through a drip or by mouth that work throughout the whole body) with local surgical management of the infection in the eye socket.
There is no topical eye drop or ointment that can treat black fungus in the eye. The infection is deep in the tissue of the eye socket, not on the surface of the eye. Black fungus medicine for eyes must therefore be administered systemically, meaning it travels through the bloodstream to reach the infected tissue.
Liposomal Amphotericin B, given intravenously, remains the primary black fungus medicine for eyes and all other forms of the infection. The dose required for rhino-orbital-cerebral mucormycosis is often higher than for other forms, and treatment duration is longer. The treating team monitors kidney function, blood counts, and electrolytes carefully throughout, as Amphotericin B can affect kidney function with prolonged use.
Eye Complications of Black Fungus: What Can Happen?
If black fungus in the eye is not treated promptly, the following complications can occur:
Orbital cellulitis Infection and swelling of the soft tissue within the eye socket, causing pain, redness, eyelid swelling, and restricted eye movement.
Cavernous sinus thrombosis A blood clot forming in the cavity at the base of the brain near the eye socket, caused by infection spreading from the sinuses. This is an extremely serious complication.
Optic nerve damage The infection or the pressure it causes can damage the optic nerve, causing sudden and often permanent vision loss.
Retinal artery occlusion The blood vessels supplying the retina can be blocked by the fungal infection, causing sudden vision loss.
Orbital exenteration Surgical removal of the eye and the surrounding fatty tissue within the eye socket. This is performed as a last resort to stop the infection from entering the brain. The patient is left without the eye and requires prosthetic rehabilitation afterwards.
This is why the message around black fungus in the eye is always the same: do not delay. Act on the early symptoms. The earlier the treatment begins, the greater the chance of saving vision and avoiding the most serious outcomes.
Black Fungus Care at Vasan Eye Care
At Vasan Eye Care, our ophthalmologists are trained to identify the eye-related signs of black fungus and to act quickly when they are suspected. The eye is often the first specialist destination for a patient with black fungus, because swollen eyelids or blurred vision may bring them to an eye clinic before they realise the extent of what is happening.
When black fungus in the eye is suspected at a Vasan Eye Care centre, our team:
- Performs an urgent clinical examination of the eye and surrounding tissue
- Coordinates immediately with ENT surgeons and other relevant specialists
- Facilitates emergency imaging and diagnostic workup without delay
- Provides clear guidance to patients and families about what is happening and what needs to happen next
- Remains involved in monitoring the eye throughout the course of treatment
We have over 150 centres across India, many of which are located in cities and regions with significant black fungus history from the 2021 period. Our team of 500+ eye care specialists is part of ASG Enterprises, India’s largest eye care network.
RELATED EYE CONDITIONS
- Orbital Cellulitis
- Uveitis
- Optic Nerve Disorders
- Retinal Vascular Occlusion
- Endophthalmitis
REFERENCES
- World Health Organization India. Mucormycosis (Black Fungus): Information and Guidelines. 2021. who.int/india/home/emergencies/coronavirus-disease-(covid-19)/mucormycosis https://www.who.int/india/home/emergencies/coronavirus-disease-(covid-19)/mucormycosis
- Wong S, Pougoue ELT, Polanco J, et al. The Black Fungus: A Rare Case of Pulmonary Mucormycosis. HCA Healthcare Journal of Medicine. 2025;6(1):95-98. pmc.ncbi.nlm.nih.gov/articles/PMC11892413 https://pmc.ncbi.nlm.nih.gov/articles/PMC11892413/
- WebMD. Mucormycosis (Black Fungus): What to Know. webmd.com/lung/mucormycosis-black-fungus-infection https://www.webmd.com/lung/mucormycosis-black-fungus-infection
- Raut A, Huy NT. Rising incidence of mucormycosis in patients with COVID-19: another challenge for India amidst the second wave? Lancet Respiratory Medicine. 2021. pubmed.ncbi.nlm.nih.gov/34043960 https://pubmed.ncbi.nlm.nih.gov/34043960/
- Directorate General of Health Services, Government of India. Evidence Based Advisory on Management of Mucormycosis in COVID-19. 2021. mohfw.gov.in/sites/default/files/Mucormycosis_guidelines.pdf https://www.mohfw.gov.in/sites/default/files/Mucormycosis_guidelines.pdf
For appointments, call 1800 571 2222 or visit your nearest Vasan Eye Care centre.
Frequently Asked Questions (FAQs)
Yes, black fungus can be treated, but success depends heavily on how early the treatment begins. When black fungus is caught in its early stages, treatment with antifungal medicines (particularly Amphotericin B) combined with surgical removal of infected tissue gives a good chance of recovery. The further the infection has spread, especially if it has reached the brain, the harder it becomes to treat and the greater the risk to life. This is why early recognition of the symptoms and immediate black fungus treatment without delay is so important.
Black fungus is managed through a combination of antifungal medicines given directly into the vein, and surgery to cut out the infected and dead tissue. The medicine kills the fungus, but because the fungus also destroys surrounding tissue and cuts off blood supply, surgery is needed to remove the areas that cannot be saved. In cases involving the sinuses, this means sinus surgery. When the eye socket is involved, more extensive surgery may be needed. Controlling the underlying condition, such as bringing blood sugar levels down in a diabetic patient, is equally important as part of the overall process.
Black fungus can affect several organs depending on the type of infection. In India, the most common form is rhinoorbital-cerebral, which means it affects the nose, sinuses, eye socket, and can reach the brain. Other forms of the infection can affect the lungs, stomach and intestines, and the skin. In the most severe cases, the infection spreads through the bloodstream and can involve multiple organs at once, including the heart and spleen. The eye is particularly at risk because of its location directly adjacent to the sinuses, which is why black fungus in the eye is such a serious concern.
For a healthy person with a normally functioning immune system, mucormycetes spores are harmless. The body’s immune cells deal with them without any infection developing. Black fungus only becomes a serious problem in people whose immune systems are significantly weakened, whether by diabetes, cancer treatment, prolonged steroid use, organ transplant medicines, or serious illness like COVID-19. This is why the vast majority of black fungus cases occur in people who already have one or more of these underlying risk factors.
Black fungus treatment is prolonged compared to most infections. Intravenous Amphotericin B is typically given daily for several weeks, and this is usually followed by months of oral antifungal medicine. The exact duration depends on how severe the infection is, how well the patient responds to treatment, and whether the underlying conditions have been brought under control. Recovery from surgery also adds to the overall treatment period. Regular monitoring with blood tests and imaging scans continues throughout the treatment to check the infection is responding.
Yes, unfortunately it can, and this is one of the most serious outcomes of black fungus in the eye. When the infection damages the optic nerve or cuts off the blood supply to the retina, vision loss can be permanent. In cases where the infection in the eye socket cannot be controlled, removal of the eye or the entire contents of the eye socket (orbital exenteration) may be required to stop the fungus from reaching the brain. This is an outcome that early diagnosis and prompt black fungus treatment can often prevent, which is why acting on symptoms immediately is so important.
Yes. While the massive surge of 2021 was closely tied to the COVID-19 second wave, black fungus was present in India before COVID-19 and continues to be a concern. India has one of the highest rates of diabetes in the world, and this remains the primary risk factor for the infection. Patients on immunosuppressants for cancer treatment, organ transplants, and other conditions remain at risk. Healthcare providers and high-risk individuals in India should remain aware of the symptoms and act quickly if they appear.
