New Mystery Fungi Species Spark Disease Warning

Several new species of fungus have been found lurking in waterways, and they might be harmful to humans.

The new species were discovered in the sediment of riverbeds across Spain. Many are closely related to species of pathogenic fungi that cause infection in humans, according to a new paper in the Journal of Fungi.

The paper notes that these types of fungus that grow in the sediment of riverbeds have not been very thoroughly studied in the past. During periods of drought they could become airborne and infect humans and animals.

"When sediments are exposed to air, these fungi may begin to produce many spores that disperse in search of a more suitable environment, and it is during this dispersion that they can interact with humans and animals," study author Josepa Gené, a researcher at the Universitat Rovira i Virgili in Spain, said in a statement.

"The infections tend to affect only the most vulnerable population and are not transmitted between humans," Gené said. "Rather, they are the result of some form of injury, among other routes of inoculation."

These fungi may also be able to infect animals and humans that swim in the rivers where they are living.

"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 the aquatic environment but also to those that they pass through it, like us when we have a swim in a river," Gené explained.

The new species of fungus fall into the category of ascomycetes, which include yeasts like Saccharomyces cerevisiae (used in baking and brewing), filamentous fungi like Penicillium (which produces the antibiotic penicillin), and various plant pathogens such as the powdery mildews and ergot fungi.

"Among their unique characteristics, fungi feed on organic matter by decomposing it, rather than ingesting it like animals do, or absorbing nutrients through roots, as plants do," Rodney Rohde, a Regents' professor of clinical laboratory science at Texas State University, told Newsweek. "Unlike bacteria, which have simple prokaryotic cells, or cells without a true nucleus, fungi have complex eukaryotic cells, which do have a nucleus surrounded by a membrane-like animals and plants.

"In the multi-level taxonomy, or naming system, that biologists use to classify lifeforms, fungi are in their own kingdom under the domain of Eukarya. Since fungi are eukaryotic-like human cells, antibiotics are not effective and we must rely on anti-fungal medications."

The research and a further investigation could help biologists understand the potential threat posed by these fungi, and identify more like them in different environments.

"These findings allow us not only to complete our understanding of the evolution of fungi but also to determine if some of these microorganisms may be a threat to our health," Gené said. "The research has just begun but the more information we accumulate in this regard, the more able we will be to determine, for example, if there is greater potential risk in a particular area and if access to some areas needs to be controlled."

The researchers plan to investigate the fungi in the lab to see how they operate and grow at human body temperature, thus determining their pathogenic potential. This will show how likely it is that the fungus could infect people during periods of drought.

"The thing is that we have a greater understanding of them now, so we can consider establishing environmental control measures. But, before we do, there is still a lot of work to be done," Gené said.

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