Just a small mutation away? New China-linked virus could be next big threat

Economic Times

06-06-2025

Agencies New China-linked bat virus could be next big threat
A group of bat viruses closely related to the deadly Middle East respiratory syndrome coronavirus (MERS-CoV) — and first identified in bats in China — may be just one small mutation away from infecting humans and potentially triggering the next global pandemic, scientists have warned. In a recent study published in Nature Communications, researchers revealed that a specific subgroup of these viruses, known as HKU5, shows worrying signs of being able to jump species, raising alarms about a possible spillover from animals to people.
The study, led by researchers from Washington State University (WSU), in collaboration with the California Institute of Technology and the University of North Carolina, focused on a lesser-known subset of coronaviruses called merbecoviruses—the same family that includes MERS, which has a human fatality rate of approximately 34%.
While most merbecoviruses appear unlikely to infect humans directly, one particular group, known as HKU5, is showing troubling potential.
'Merbecoviruses — and HKU5 viruses in particular — really hadn't been looked at much, but our study shows how these viruses infect cells,' said Michael Letko, virologist at WSU's College of Veterinary Medicine. 'What we also found is HKU5 viruses may be only a small step away from being able to spill over into humans.' Using virus-like particles engineered to contain only the receptor-binding portion of the virus's spike protein, the researchers demonstrated that HKU5 viruses can already use the ACE2 receptor—the same receptor used by SARS-CoV-2, the virus that causes COVID-19. However, for now, HKU5 viruses bind more efficiently to bat ACE2 and do not infect human cells effectively—yet.
The viruses were originally discovered in Japanese house bats (Pipistrellus abramus), but recent studies suggest some HKU5 strains may already be jumping to intermediate hosts such as minks, a key step that could lead to human infections.'These viruses are so closely related to MERS, so we have to be concerned if they ever infect humans,' Letko cautioned. 'While there's no evidence they've crossed into people yet, the potential is there — and that makes them worth watching.'The team also deployed artificial intelligence tools, such as AlphaFold 3, to simulate how HKU5's spike protein interacts with the ACE2 receptor at a molecular level. The AI-generated models matched results produced by traditional lab methods, but in a fraction of the time, significantly speeding up the understanding of how the virus might evolve and evade immune defenses.