A fungus that thrives in compost is posing an increasing threat to human health because of climate change, experts have warned, and it can rapidly adapt, becoming resistant to drugs
Experts have warned that a commonplace fungus could begin to pose a massive threat to human health as the climate crisis progresses. Aspergillus fumigatus is present in the air and soil, and in damp and warm places like compost heaps absolutely thrives – and it can cause serious and long-lasting health problems in some people.
This includes chronic lung infections that sometimes must be medicated for a lifetime, and can even be fatal. Currently, around 4000 people each year in the UK suffer from the most severe form of the infection – invasive aspergillosis – which can be deadly. Experts say the mortality rate can be up to 85 percent, even when treated with powerful antifungal medications.
Those who have weakened immune systems are currently the most vulnerable to fungal infections like this – but climate change could mean that even healthy people come under threat, as mutations of the fungi make them even more infectious and resistant to medicines.
Higher temperatures across Europe caused by the climate emergency are already causing increased spread and growth of aspergillosis. This could create “significant public health concerns,” according to a new study published last month.
The ability of fungi to adapt easily and quickly is a key component in what makes it such a threat. According to the report, “rising temperatures, changing precipitation patterns, and extreme weather events are thought to be driving the adaptation of fungal pathogens to new climates, expanding their geographical range and posing a growing threat to human health and agriculture.”
Despite the growing concerns from researchers, chronic fungal infections like aspergillus bronchitis are often misdiagnosed, leading to delays in treatment. Viv Goosens, Research Manager at Wellcome Trust, explained to The Mirror, that this is due to a “combination of factors”.
“Firstly, aspergillus bronchitis can be easily misdiagnosed for more common respiratory diseases or allergic reactions due to the similarity of symptoms. Secondly, fungal infections aren’t usually the first thing doctors think of—especially in people with healthy immune systems—so the diagnosis can be delayed. And even when it’s suspected, confirming it isn’t straightforward. It requires a specialised test that isn’t always easy to access.”
For 14 years, mum-of-two Lisa McNeil, 54, battled chronic chest infections, with her doctors none the wiser about why no treatment was working.
In 1998, a year after having her first child – and suffering a lung injury whilst pregnant – Lisa’s health difficulties began, and after enduring a repeated cycle of being hospitalised for chest infections, she was eventually diagnosed with a condition called bronchiectasis.
This occurs when the bronchi in the lungs – the small airways – get too wide, which leads to an excess of mucus and makes someone more susceptible to infections.
However, it would be over a decade until her medical team realised that Lisa had in fact not been battling bacterial infections all this time. Instead, her lungs were home to a fungus called aspergillus fumigatus.
Since 2011, Lisa has been taking a series of intense antifungal medications in an attempt to treat her chronic fungal infection – including one that is so poisonous, that she can only take it whilst in a room by herself, that is properly ventilated.
The medications have had varying degrees of success, Lisa explained to the Daily Mail. She was first put on voriconazole, which stops the fungus from growing by attacking the cells, but she experienced intense visual side effects, and it didn’t work for her.
Her medical team at the National Aspergillosis Centre in Manchester then tried her on amphotericin B, which each day she had to use a device to inhale.
“Only one in five patients can tolerate it,’ she told the publication. “It gives you a sore throat and nausea for about an hour after taking it. Because of the toxicity, you have to be on your own in a room with an open window, and no one can enter the room for 30 minutes.
“Despite all that, it was brilliant. The drug made such a difference for my health and energy levels. Even my constant cough went away.”
However, the drug is too toxic for patients to take for an extended period, so after three years she had to stop to avoid dangerous complications like damage to her kidneys and anaemia.
At the moment, Lisa is taking the antifungal medication itraconazole, and has recently suffered from bouts of ill health after picking up bacterial infections alongside her aspergillus bronchitis.
Experts have warned that due to the climate crisis, stories like Lisa’s may become even more common because Aspergillus fumigatus is prolific.
One of the study’s authors, Dr Norman Van Rhijn, explained to the Mail that the UK already has higher levels of aspergillosis in places like compost heaps and bags and that when the compost is moved it is able to move easily through the air.
Viv Goosens explains that “Aspergillus spores are everywhere in the environment but typically don’t cause infection,” adding that this is because “a healthy immune system can fend off infections effectively.
“However, there are times when our immune systems are weakened, due to other infections or chronic conditions, where we may be more susceptible to fungal infections. When this is the case, it is advisable to wear a mask and to avoid high risk areas.”
Goosens adds that if you are concerned about your risk level for encountering these spores then you should speak to a healthcare professional.
Research has predicted that “the spread of Aspergillus fumigatus could increase by 77.5 percent and potentially expose 9 million people in Europe,” and Aspergillus flavus – one of the most resistant to antifungal meds, could expose one million to severe and deadly infection.
Diagnosing fungal infections of this kind is, as the experts have noted, no mean feat, but they can also be very tricky to treat. There is one major reason why, according to the researchers: “As fungi are more similar to humans than other pathogens, developing anti-fungal treatments without toxic side effects is challenging.”
Not only that, but common agriculture practices mean that the medications that are available are themselves under threat – as the fungus rapidly adapts, becoming resistant to even the most cutting-edge treatments.
“Their spread is accelerated by globalisation, urbanisation, and the intensifying use of agricultural fungicides, which further increase antifungal resistance,” the study explained.
Fungicides are used widely in agriculture, and many of them work similarly to the antifungal medications being developed, with a large overlap in their chemical makeup – presenting a massive problem. “A lot of the fungicides used in farming are either identical or really similar to the antifungal drugs that we rely on in medicine,” Goosens explains. “That means fungi out in the environment can start building resistance to treatments we use to fight infections in people. “
It’s much faster and easier for fungicides to be approved compared to antifungal medications, which means that fungi are presented with an opportunity to learn how to adapt to them when they are sprayed on crops at an industrial level. By the time the medications are approved, they can be rendered ineffective.
Two antifungal medications that are currently undergoing clinical trials, olorofim and fosmanogepix, in humans, are poised to be approved in the UK right now – giving the fast-adapting fungi a two-year head start.
“To tackle this, we need better communication between the agriculture and healthcare sectors,” Goosens explains, “and stronger government oversight to make sure we’re using these chemicals responsibly.”
One of the major issues, the expert explains, is that so little is known about fungi – and much more research is needed into them. “Fungi are a huge part of life on Earth, but we’ve barely scratched the surface in understanding them. That really needs to change, especially as the climate shifts.
“We need more research into their basic biology, better tools to diagnose fungal infections, and stronger systems to keep an eye on how fungi are spreading or changing. They don’t exist in isolation—they’re part of wider ecosystems, and they’re adapting in ways we’re only just beginning to understand.
“Sometimes that means a fungi that’s normally harmless can start causing disease, or it can evolve to survive in new environments. We’ve only identified a tiny fraction—less than 10%—of all fungal species out there. There’s so much potential, not just for treating and preventing infections, but also for discovering new medicines and other breakthroughs. We just need to start paying more attention to them.”