The Aspergillus fungus, long known for its role in breaking down natural materials, is now turning into a growing global threat. Researchers warn that it could pose serious risks to human health, food systems, and the environment. As climate change, widespread fungicide use, and weakened immune systems increase, this fungus is spreading faster and becoming more dangerous.
The fungus releases invisible spores into the air. People breathe these spores every day without noticing. For most, the immune system keeps them safe. But in hospitals, farms, and homes, these spores are becoming harder to control. The fungus can cause lung infections, destroy crops, and survive medicine that used to kill it.
A group of scientists from the University of Manchester studied three major species of Aspergillus: A. flavus, A. fumigatus, and A. niger. They used climate models to see where the spores might go in the future. One of their worst-case models, based on high fossil fuel use, shows that these fungi will spread much farther across Europe by the end of this century.
Aspergillus fungus is flexible. It can live in soil, grain, feathers, and even coral. While it plays an important role in nature by recycling dead materials, it becomes harmful in fields and hospitals. Farmers use azole sprays to protect crops like wheat and peanuts. Doctors use similar azole medicines to treat infections. Over time, this overlap has made Aspergillus more resistant to both kinds of treatment.
Rising heat, more humidity, and extreme weather are helping these spores travel and settle in new places. According to Dr. Norman van Rhijn, changes in the climate are giving this fungus more chances to adapt and spread. Already, the Candida auris fungus has emerged because of global warming. Now, Aspergillus could follow the same path.
The team’s model showed that the range of A. flavus in Europe could grow by 16 percent. That could put one million more people at risk. Even more alarming, A. fumigatus might expand by over 77 percent, possibly affecting nine million more people.
But the impact is not the same everywhere. In parts of Africa, for example, the heat may become too intense for these fungi to survive. This shows how climate change can shift the balance in complex ways, sometimes making regions safer and other times more dangerous.
Hospitals are already struggling with Aspergillus outbreaks, especially after renovations or dust storms. Patients recovering from serious illnesses like flu or COVID-19 are more likely to get infected. As the number of spores in the air grows, hospital cases and treatment costs may rise.
The problem extends to food as well. A year of heavy Aspergillus growth can cost the U.S. corn industry over $1 billion. Warmer, wetter weather helps mold grow in storage silos and fields. This leads to grain loss or mixing, which can harm both health and income.
Even worse, the drugs that work against Aspergillus are becoming less effective. Resistance is rising in Europe and Asia. When the fungus no longer responds to treatment, death rates can exceed 50 percent. The remaining drugs often harm the kidneys or liver, adding to the risk.
Each time a farmer sprays azole fungicide, the chances increase that Aspergillus in the soil will carry drug-resistant genes. These spores can reach hospitals and infect patients. Public health experts now monitor soil and compost for these genes to catch outbreaks early.
As the climate keeps changing, some regions may use even more fungicides. That creates a cycle: more spraying leads to stronger resistance, which affects both health and food supply.
Other fungi like Fusarium and Cryptococcus are also adapting to the warmer world. These threats are no longer rare. In 2022, the World Health Organization added Aspergillus fungus to its list of urgent health dangers.
To fight this problem, experts suggest new ways to track and control the fungus. Air sensors, farm testing, and hospital checks can give early warnings. These steps can help guide safer use of fungicides and improve diagnosis tools.
Stopping the spread won’t be easy, but small actions can make a big difference. Lowering emissions slows climate change. Smarter use of fungicides reduces resistance. Better building design can keep spore levels low indoors. And new medicines can give doctors more treatment options.
These efforts, taken together, can help turn Aspergillus fungus from a growing danger back into a natural helper.
