Researchers have discovered a drug-resistant super fungus in one of the most remote corners of the Earth. This finding from a disturbing new study raises fears of a widespread disease outbreak capable of making millions sick.
The researchers hail from McMaster University and have published their findings in the scientific journal, mSphere.
Researchers collected the disease-causing super fungus, Aspergillus fumigatus, from the Three Parallel Rivers region in Yunnan, China. A staggeringly beautiful yet remote part of the world, this region perches 6,000 meters above sea level. It is cloaked by the towering, icy peaks of the Eastern Himalayas.
Few people live here, and there's minimal development. Yet this is where the research team discovered the drug-resistant super fungus strains. Seven percent of the Aspergillus fumigatus samples collected there were drug resistant.
Intrigued, Jianping Xu, the leader of the study, decided to investigate further. "Seven per cent may seem like only a small number, but these drug-resistant strains are capable of propagating very quickly and taking over local and regional populations of this species," explained Xu.
Jianping Xu is a biology professor at McMaster University, and a member of the Michael G. DeGroote Institute for Infectious Disease Research. Xu's words emphasize the need for thorough monitoring of drug resistance across varying geographic locations.
This latest study is the final part of a trilogy of related research pieces led by Xu and his team. In the first study, they found that about 80 per cent of Aspergillus fumigatus samples collected from greenhouses in Yunnan resisted common antifungal drugs.
The second study revealed a similar resistance in around 15 per cent of samples taken from Yunnan's agricultural fields, lake sediments, and forests.
Xu, who also contributes to the Global Nexus School for Pandemic Prevention & Response, suggested evidence is mounting for natural development of resistance in the environment.
Interestingly, he also points out that these resistant Himalayan strains of Aspergillus fumigatus likely originated from the spores of other fungi. Different settings had overexposed these spores to agricultural fungicides.
The fact that these resistant spores can potentially migrate to such remote areas and reproduce there is a global concern.
"This fungus is highly ubiquitous - it's around us all the time," Xu explained. He added, "We all inhale hundreds of spores of this species every day. While it doesn't always cause noticeable health problems, three to four million people experience disease symptoms caused by Aspergillus fumigatus each year. It can be very dangerous. It can lead to lung removal or even death. Now, increasingly, many of these infections will be impacted by drug resistance."
Xu's research has already discovered similar mechanisms of resistance in fungi strains located in the Northwest Territories and India. These locations are a vast 10,000 kilometers apart, another concerning revelation.
"Unlike viruses like COVID-19, fungi don't need a host to spread," Xu explained. "They can travel on humans, through trade, and even on strong winds."
With this in mind, Xu plans to return to the mountainous regions of China to collect air samples for fungal spores. He hopes to shed more light on how these resistant strains are reaching and flourishing in such remote regions.
Aspergillus fumigatus is a species of fungus that is widespread in the environment. It is one of the most common Aspergillus species to cause disease in individuals with an immunodeficiency. Here's what we know:
Aspergillus fumigatus is found in various environments worldwide. These locations include soil, plant debris, and indoor environments. It thrives in areas with high organic content. This species produces large amounts of airborne conidia (spores). They are easily inhaled by humans and animals due to their small size.
Most people inhale Aspergillus fumigatus spores every day without getting sick. However, in individuals with weakened immune systems, such as those with leukemia, organ transplant recipients, or those with AIDS, this fungus can cause a variety of diseases.
Invasive aspergillosis is the most severe disease caused by Aspergillus fumigatus. This is a rapidly progressive, often fatal disease affecting primarily the lungs. However, it can also spread to other parts of the body.
Other diseases caused by this fungus include allergic bronchopulmonary aspergillosis (ABPA). This is a hypersensitivity reaction in individuals with asthma or cystic fibrosis. It also causes aspergilloma. This is a 'fungus ball' that can form in pre-existing lung cavities caused by conditions such as tuberculosis.
Resistance to antifungal drugs is an emerging problem with Aspergillus fumigatus. The primary mechanism of resistance is via mutations in the cyp51A gene. Worldwide agricultural use of azole fungicides often leads to exposure that associates with this gene.
Diagnosis can be challenging and often involves a combination of imaging studies. These are a combination of direct detection of the fungus in clinical samples (microscopy, culture), and indirect detection (e.g., serology, PCR).
Treatment often involves antifungal drugs, notably the azoles. However, alternatives like amphotericin B and echinocandins are used in cases of azole resistance.
Scientists continue to study Aspergillus fumigatus to better understand its biology. They are seeking to learn more about the diseases it causes and how to best treat those diseases.
Fungi are a diverse group of organisms that play a crucial role in nutrient cycling and decomposition in ecosystems. However, some species can also cause diseases in plants, animals, and humans. Here's what you need to know:
Fungi are classified into their own kingdom, separate from plants and animals. They are eukaryotes, meaning their cells have a nucleus and other organelles. Fungi can exist as yeasts, molds, or a combination of both. They reproduce through spores, which can be asexual or sexual.
Fungi can survive in a wide range of environments, from deserts to the deepest parts of the oceans. They are particularly abundant in moist, warm environments.
Many are decomposers, breaking down dead organic material. Others are mutualists, forming beneficial relationships with other organisms like plants and animals. However, some are parasites, causing harm to their host.
Fungi reproduce and spread primarily through spores. Fungi spores are often produced in very large quantities. The spores are tiny and lightweight, so they can travel long distances through the air or water. They can also be transported by animals or humans.
Some fungi also spread through vegetative growth. They accomplish this by extending their hyphae (the branching filaments that make up the body of the fungus) into new areas.
Some fungi can cause diseases, known as mycoses, in humans and other animals. These can range from superficial infections affecting the skin or nails (like athlete's foot or ringworm), to deeper infections affecting internal organs (like histoplasmosis or aspergillosis).
Many fungi are opportunistic pathogens. They cause disease primarily in individuals with weakened immune systems.
Fungi also cause many plant diseases. This can have significant impacts on agriculture and natural ecosystems. These plant diseases include rusts, smuts, and mildews, as well as rots of roots, stems, leaves, and fruits.
Preventing fungal infections often involves maintaining a healthy immune system and good hygiene practices. For plant pathogens, strategies can include the use of resistant varieties, crop rotation, and fungicides.
However, the widespread use of fungicides, especially in agriculture, has led to increasing concerns about the development of antifungal resistance. This is similar to antibiotic resistance in bacteria. As a result, researchers are actively seeking new strategies for fungal disease control.
Despite their potential for causing disease, fungi also have many beneficial uses. They are used in baking and brewing. Fungi are also an important part of the production of antibiotics and other drugs. Finally, they are key components used in biotechnology for the production of enzymes, proteins, and biofuels. Some fungi also form beneficial relationships with plants, aiding in nutrient uptake.