The increase in temperatures will lead to the global spread of a killer fungus that infects millions of people a year, according to new research on how climate change attaches serious threats to illness.
The Aspergillus family could extend its scope to bands more northern from Europe, Asia and the Americas, highlighting the stealth threat of the molds already estimated as a factor in 5% of all deaths in the world.
Climate change widens the geographical scope of many potentially fatal pathogens, such as those worn by mosquitoes. Mushrooms are a particular danger, due to their spores that are difficult to detect, a shortage of treatments for the diseases they trigger and increasing resistance to existing drugs.
The world is now approaching a “tilting point” in the proliferation of fungal pathogens whose habitats range from arid soil to the hot wet corners of houses, warned Norman Van Rhijn, co-author of the new Aspergillus research.
“We are talking about hundreds of thousands of continental lives and changes in species distributions,” said Van Rhijn, a wellcomme Trust researcher at Manchester University who specializes in fungal infections and microbial evolution. “In 50 years, where things grow up and what you are infected with going to be completely different. “”
The fictitious fungus that changes the brain described in the post-apocalyptic television series The last of us While wiping a large part of humanity has brought the threat to a wider audience. But the danger in the real world is always underestimated.
Mycology, the study of fungi, is an area of many mysteries. More than 90% of fungal species “Stay unknown to science”According to a report in 2023 of the Royal Botanic Gardens of the United Kingdom, Kew. This makes them much less well understood than the main parts of the plant and animal kingdoms.
About 3.8 million people each year die with Invasive fungal infectionsPathogen being the main cause of death in 2.5 million of these cases, according to research published last year.
A leading danger is aspergillosis, a pulmonary disease caused by aspergillus spores which can spread to other organs, including the brain. Many infections are spotted late or neverDue to the ignorance of doctors or because the symptoms are confused with those of other conditions.
Aspergillus, named in the 18th century for its resemblance to a device used to sprinkle holy water, has brought advantages in humanity and in danger.
Some species have uses ranging from industrial chemistry to the fermentation of soy sauce and sake, but others are potentially dangerous for health.
Although most people do not fall sick by inhaling Aspergillus spores, the mortality rate can be high if the infection takes root. They are a particular threat to the growing number of people with immune systems weakened by conditions such as asthma or cystic fibrosis, or by medical treatments such as chemotherapy.
Species Aspergillus fumigatus was appointed as one of the four critical fungal pathogens that posed highest riskAccording to the very first list of threats published by the World Health Organization in 2022.
The last fungal search, funded by Wellcoma And released on Saturday, said that A. Fumigatus could spread to 77% additional territory by 2100 if the world continues to strongly use fossil fuels. Its scope would push to the North Pole, exposing 9 million additional people in Europe to infection.
The species can develop “surprisingly quickly” at high temperatures in the compost in which it lives, said Professor Elaine Bignell, co -director of the MRC Center for Medical Mycology at the University of Exeter.
This could have equipped it to survive and prosper in the temperatures of the human body of around 37 ° C. “Its lifestyle in the natural environment can have provided A. Fumigatus With the advantage of fitness necessary to colonize human lungs, ”said Bignell.
A second species in the latest study, Aspergillus flavus, Lives on many cultures and could spread in 16% of the territory by 2100, the researchers' project.
This would give it new or more important taxes in northern China, Russia, Scandinavia and Alaska, while manufacturing existing habitats in African countries and inhospitable Brazil. This disappearance would have mixed effects because it would disrupt ecosystems in which Aspergillus plays a vital role in recycling crucial chemicals in life.
The prospect of A. Flavus The geographic spread was “potentially very disturbing,” said Darius Armstrong-James, professor of infectious diseases and medical mycology at the Imperial College in London. Research suggested that the species had caused disease epidemics in countries like Denmark, he added.
A. Flavus Also produced harmful chemicals called aflatoxins which can cause cancers or potentially fatal liver damage. Higher temperatures and CO levels can increase the Toxins production And contaminating his harvest hosts found scientists.
“There are serious threats from this organization both in terms of human health and food security,” said Armstrong-James, adding that recent data suggested A. Flavus can develop strong resistance to fungicides.
The development of antifungal drugs has been hampered by the Financial antactive to invest in them, due to high costs and doubts about their profitability.
Aspergillus' new research adds to an increasing set of work that suggests extreme weather events and related phenomena such as forest fires are likely to stimulate the spread of dangerous fungi.
Dreams followed by heavy rain can trigger soil disturbances and a release of spores in the air, said Brittany Bustamante, a scientist from the University of California to study the epidemiology of aspergillosis.
UC Berkeley runs a five-year project to use megadata to analyze medical records of 100 million patients in the United States, in order to identify the factors that affect the incidence and severity of fungal infections.
Researchers discovered that fungal pathogens such as coccidioides, the cause of the fever of the potentially serious respiratory valley, propagate After drought and other climate -related changes.
Coccidioides, which lives in the soils of the warm and dry regions, has already widened its habitat from the southwest of the United States in the state of Washington.
Since 2020, the data suggests that the largest increases in aspergillosis were in Latin individuals and the people who lived in rural areas, said Bustamete.
The reasons for this were not clear, but could be linked to people who had had a severe covid – and who may not have access to treatment from exceeded health systems.
“Given the potential for climate change to stimulate future overvoltages in respiratory diseases, secondary fungal infections like aspergillosis should remain a serious public health problem,” said Bustamente. “And the most risky people will probably be those who are already faced with structural drawbacks and greater exposure to environmental risks such as pollution.”
