New species of fungi potentially harmful to humans identified in freshwater ecosystems

A study by the Mycology and Environmental Microbiology Unit of the Universitat Rovira i Virgili has identified new species of fungi that can cause infections or diseases in people and animals. Conducted in river ecosystems, the research is part of a project on biodiversity and the role played by ascomycetes, a large group of fungi, in aquatic ecosystems.

Little is known about these fungi, especially those that grow in sediments. The research also warns that some pathogens are more likely to occur during periods of drought. Species are even more dangerous to people’s health.

Ascomycetes both fluvial and Marine sediments Little has been studied so far, and what we are doing in this project is not only expanding the knowledge base about the species found in these sediments, but also determining patterns of biodiversity. which indicates whether an ecosystem is healthy or, conversely, pollution problems from various sources.”

“In short, any change in the composition of the fungal community can be a warning that something is wrong,” says Joseph Jain, principal investigator of the study.

Some species in this community may spread more readily under certain conditions and may be used as environmental bioindicators. “But other fungi are opportunistic pathogens of mammals, cold-blooded animals, and other creatures, which can cause mild and serious infections, not only in animals that live in aquatic environments but also in those exposed to them. pass, like when we. We have a swim in the river,” explains Jenny.

If the environment changes – for example, during a drought – they can become exposed and threaten the health of the habitats. “When the sediment is exposed to air, these fungi can begin to produce many spores that disperse in search of a more suitable environment, and during this dispersal they come into contact with humans and animals,” she says. can communicate,” she says.

In any case, she points out that “infections only affect the most vulnerable populations and are not transmitted between humans. Rather, they are the result of some form of injury other than by other routes of inoculation.” “

According to Gené, the results of the project confirm that river sediments are an important reservoir of fungal biodiversity and include species that are completely unknown to science. Therefore, they are a legacy that must be preserved. Importantly, the study found previously unreported fungi, some of which were found to be closely related. Pathogenic fungi which cause very serious infections in the Americas.

“These findings allow us not only to complete our understanding of the evolution of fungi, but also to determine whether some of these microorganisms may pose a threat to our health. The research has only just begun. But the more information we collect in this regard, the more we’ll be able to determine, for example, if a particular area is more likely to be at risk and if access to certain areas needs to be controlled. need,” says Jain.

The Mycology and Environmental Microbiology Unit of the Universitat Rovira i Virgili studies strains of sedimentary fungi collected at different sites along different Catalan rivers—for example, the Llobregat, Ter, Segre, and Ebro—and smaller streams. too

Once they are cultured in the laboratory, they are tested to determine their pathogenicity (i.e., if they can grow at 36 or 37 degrees Celsius, human body temperature), and is explored. What happens when they are exposed to human cell cultures and how resistant they are to antifungal drugs.

All this will make it possible to determine whether climate change conditions (drought, high temperatures, etc.) enable them to spread more easily and represent a threat.

In any case, Gené says there’s no need to panic—”Just be careful, yeah,” she says—because these fungi have always been there.

“The point is that we now have a better understanding of them, so we can consider establishing environmental control measures. But, before we do, there is still a lot of work to be done,” says Gené. . She concludes by highlighting the importance of biodiversity as it leads to greater balance and consequently better coexistence between species and fewer threats to both human and environmental health.

Here is the research. published I Journal of Fungi.