Nature study finds critical defense against black fungus

Your Blood Already Has a Defense Against Black Fungus. Scientists Just Figured Out How It Works.

Mucormycosis is the kind of fungal infection that makes the others look manageable. Fast-moving, frequently fatal, and notoriously resistant to treatment, it's caused by Mucorales fungi and can spread through the body so rapidly that even a prompt diagnosis doesn't guarantee survival. In some patient groups, the mortality rate approaches certainty rather than probability.

A major international study published in the journal Nature has now identified something that was sitting in plain sight: the most common protein in human blood turns out to be one of the body's primary defenses against this infection, and low levels of it are the strongest predictor of severe outcomes and death.

The protein is albumin. The research was led by George Chamilos and his team at the University of Crete and the Institute of Molecular Biology and Biotechnology, with key contributions from Professor Ashraf Ibrahim's group at The Lundquist Institute for Biomedical Innovation. The findings have the potential to change how clinicians screen for and treat mucormycosis in vulnerable patients.

What Mucormycosis Actually Is

Black fungus, as mucormycosis became widely known during the COVID-19 pandemic, is not a single disease but a category of infection caused by the Mucorales order of fungi. These organisms are found widely in the environment and cause little harm to people with healthy immune systems. In patients with compromised immunity, uncontrolled diabetes, or significant malnutrition, however, they can invade tissue rapidly and with devastating consequences.

The infection typically begins in the sinuses or lungs and can progress into the brain, the eye sockets, and other organs within a very short timeframe. It is fatal in roughly half of all cases overall, and substantially more in those with certain underlying conditions. Treatment currently involves aggressive antifungal medication, often combined with surgical removal of infected tissue, and outcomes depend heavily on how quickly the diagnosis is made and whether the patient's underlying condition can be brought under control.

Cases surged dramatically in India during the second wave of COVID-19 in 2021, particularly among diabetic patients treated with corticosteroids, producing a secondary public health emergency that drew significant global attention to a disease that had previously been largely unfamiliar outside specialist infectious disease circles.

WHO Fungal Priority Pathogens List

Low Albumin: The Missing Piece in the Risk Picture

Albumin is produced by the liver and makes up more than half of the total protein in human blood plasma. Its primary role is maintaining fluid balance in the bloodstream, but it also transports hormones, fatty acids, and other compounds around the body. Conditions that deplete albumin, including liver disease, malnutrition, kidney disease, and severe systemic illness, are collectively described as hypoalbuminemia.

The research team found that patients diagnosed with mucormycosis had significantly lower albumin levels than patients dealing with other types of fungal infections. When they analysed outcomes across diverse patient groups on multiple continents, low albumin consistently emerged as the factor most strongly associated with severe illness and death. It outperformed other risk predictors as a signal for who was most likely to deteriorate.

This finding reframes how clinicians might think about mucormycosis risk. Rather than waiting for infection to establish and then treating aggressively, the albumin biomarker offers a potential early warning system. Patients with hypoalbuminemia who are in high-risk categories, such as those with diabetes, blood cancers, or immunosuppressive treatment, could be identified before infection takes hold and managed accordingly.

Ibrahim described the discovery as a remarkable finding with the potential to genuinely shift clinical practice around mucormycosis care.

How Albumin Blocks the Fungus

The clinical observation that low albumin correlates with worse outcomes would be useful on its own. What makes this study particularly significant is that the team went further and worked out the mechanism behind the correlation.

Albumin, it turns out, doesn't just happen to be present when Mucorales fungi fail to establish. It actively disrupts the biological processes the fungus relies on to invade human tissue. The mechanism centers on fatty acids that are attached to the albumin protein. These fatty acids interfere directly with fungal metabolism and block the production of proteins the fungus needs to penetrate tissue and drive disease progression.

Laboratory experiments confirmed this mechanically. When albumin was removed from healthy human blood samples, Mucorales fungi multiplied freely. When albumin was present at normal levels, fungal growth was substantially suppressed. Animal experiments reinforced the finding: mice without albumin were highly susceptible to infection, while restoring albumin to normal levels provided significant protection.

The research also identified an additional layer to the story. Blood samples from mucormycosis patients showed elevated rates of fatty acid oxidation, which appears to strip the protective fatty acids from albumin and leave it less effective as an antifungal agent. This may help explain why certain underlying conditions, particularly those that disrupt lipid metabolism, create such dramatically elevated infection risk.

The Lundquist Institute can be found here.

What This Opens Up for Treatment

The practical implications run in two directions: prevention and treatment.

On the prevention side, albumin enriched with fatty acids could potentially be administered to high-risk patients as a protective measure before infection establishes. Given the speed at which mucormycosis progresses once it takes hold, a preventive strategy is significantly more attractive than relying entirely on early diagnosis and aggressive intervention after the fact.

On the treatment side, the identification of albumin's mechanism gives researchers a clearer picture of the specific virulence factors in Mucorales fungi that can be targeted. Ibrahim's team at The Lundquist Institute is currently developing immunotherapies aimed at those targets, and the Nature study raises the possibility of combining albumin-based therapy with these immunological approaches to produce a more complete treatment strategy.

This matters because current antifungal medications for mucormycosis are limited and often harsh. Amphotericin B, the most effective treatment available, carries significant toxicity. The development of complementary approaches that work through the body's own defense mechanisms rather than relying entirely on pharmaceutical intervention represents a meaningfully different direction.

ShroomSpy functional mushroom supplements & resources

The Broader Pattern in Fungal Infection Research

This study joins the butyrolactol A research from McMaster University, the marine fungal predator discovered by Yokohama National University, and a growing body of work pointing toward the same conclusion: the scientific understanding of how fungi interact with human biology has been substantially incomplete, and closing that gap is producing genuine medical advances.

For the mycology community, the albumin discovery is a useful reminder that the fungal kingdom operates through mechanisms far more sophisticated than most people appreciate. The same biological complexity that makes mushrooms nutritionally and medicinally interesting also drives the pathogenic capacity of Mucorales and Cryptococcus. Understanding one side of that complexity feeds into understanding the other.

Functional mushrooms like turkey tail, reishi, and lion's mane are the subject of serious ongoing research partly because they interact with immune function in ways that are still being characterised. The albumin study is a reminder of how that immune landscape actually works and how much of it remains to be mapped.

Ready to take your mycology journey to the next level? Browse our full range of mushroom products at and find everything you need to grow, forage, and thrive.

FAQ

What is mucormycosis?

Mucormycosis, sometimes called black fungus, is a serious and often fatal infection caused by Mucorales fungi. It primarily affects people with weakened immune systems, diabetes, or malnutrition. The infection can spread rapidly through the sinuses, lungs, and other organs, and carries a mortality rate of roughly 50 percent overall, with significantly higher rates in certain patient groups.

What is albumin and why does it matter for fungal infections?

Albumin is the most abundant protein in human blood plasma, produced by the liver. A large international study published in the journal Nature in March 2026 found that low albumin levels are the strongest predictor of severe outcomes and death in mucormycosis patients, and that albumin actively suppresses Mucorales fungal growth through fatty acids bound to the protein.

What is hypoalbuminemia?

Hypoalbuminemia is the clinical term for abnormally low albumin levels in the blood. It is associated with liver disease, malnutrition, kidney disease, and severe systemic illness. The research identified hypoalbuminemia as a key biomarker for mucormycosis risk that could allow earlier identification of vulnerable patients.

Could albumin be used as a treatment for mucormycosis?

The research suggests albumin enriched with fatty acids could potentially be used to protect high-risk patients before infection establishes. It may also be combined with immunotherapies targeting Mucorales virulence factors, which are currently in development at The Lundquist Institute. Both approaches are in the research phase and are not yet available as clinical treatments.

Who is most at risk of mucormycosis?

People with poorly controlled diabetes, those undergoing immunosuppressive treatment, individuals with blood cancers, and malnourished patients are at highest risk. The infection surged in India during the COVID-19 pandemic, particularly among diabetic patients treated with corticosteroids.