Scientists in Barcelona have made a significant discovery, identifying a new hybrid fungus that has the potential to pose a threat to global health. The fungus, known as Candida orthopsilosis, is believed to have originated from two parent strains in a rare event called hybridization, which was likely influenced by climate change.

The researchers revealed that this new super-strain of fungus has acquired specific properties, including the ability to infect the human body, thrive in higher temperatures, and resist antifungal drugs. They believe that as temperatures continue to rise and ecosystem conditions change, hybridization events like this could become more common. Factors such as globalization and human actions, such as the widespread use of fungicides and antibiotics in agriculture, may also contribute to the emergence of such strains.

Lead researcher Dr. Toni Gabaldón from the Institute for Research in Biomedicine (IRB Barcelona) explained that hybridization has received little attention until now, but it allows for the rapid acquisition of properties that enable human infection. This process could serve as a shortcut for fungi to adapt and conquer species like ours.

The significance of hybridization lies in the fact that it brings together divergent genomes and alleles, increasing genomic plasticity and facilitating adaptation. Divergent genomes refer to the accumulation of mutations over time in populations of ancestral species, while alleles are different forms of a gene found at the same place on a chromosome.

In an eerie twist, the researchers noted that the plot of the recent HBO miniseries "The Last of Us" mirrors the discovery of this hybrid fungus. The miniseries portrays a scenario where a fungus rapidly acquires the ability to infect, transmit, and exhibit high virulence, ultimately leading to the devastation of humanity.

The newly discovered fungus belongs to the Candid family, which is known to cause infections such as vaginal candidiasis and systemic candidiasis, which can be fatal for individuals with weakened immune systems. The super-strain has demonstrated the ability to infect human hosts, thrive in higher temperatures, and develop resistance to antifungal drugs.

It is estimated that there are over one million species of fungi, with many adapted to live in temperate or low-temperature environments such as soil, aquatic settings, trees, plants, and various animal species including amphibians, fish, reptiles, and insects.

The researchers also made an alarming observation: they identified one parental lineage within the hybrid fungus that passed on enriched membrane and cell-wall-related proteins, potentially contributing to its virulence, adhesion, and pathogenicity. This raises concerns regarding the spread of this fungus, as health authorities have already detected it outside of hospitals for the first time.

The study published in Nature further indicates that the warm sea water environment may serve as a melting pot where these hybrid lineages emerge, surpassing the thermal barrier previously considered protective against fungal infections in mammals. This suggests that humans could now be vulnerable to this newly discovered hybrid fungus.

In their research, the team also discovered that a deadly fungus known as C. Auris, which emerged in humans in 2009, may also be a hybrid that formed in the marine environment before infecting humans. This underscores the potential impact of climate change on the emergence of pathogenic microorganisms.

The scientists examined nine yeast samples from the Arabian Sea, specifically from the coast of Qatar, and found that nearly all of them were hybrids. These findings led them to propose that these fungi have likely undergone adaptations that give them an advantage over their parental strains.

This discovery highlights the urgent need for further research and vigilance in monitoring the emergence and spread of hybrid fungal strains. The potential threat they pose to global health underscores the importance of addressing climate change, as rising temperatures and changing ecosystems create an environment that allows these potentially dangerous mutations to occur.