Scientists have identified a new bat virus in China, HKU5-CoV-2, that is genetically similar to COVID-19 and MERS. Though it currently poses little threat to humans, experts warn it could mutate into something dangerous. “HKU5 viruses may be only a small step away from being able to spill over into humans,” said Prof. Michael Letko of Washington State University.

The virus, found in bats, doesn’t yet bind to human cells unless it mutates. However, if it jumps to another animal first—an “intermediate host”—it could evolve and gain the ability to infect humans. Letko’s team used lab-made “pseudoviruses” to test this potential and found that while HKU5 can’t infect human cells yet, it’s close.

Despite the concern, experts stress that HKU5 is weaker than COVID-19. “There is little chance of a pandemic comparable to COVID-19,” noted researchers. Dr. Mark Siegel of NYU Langone Health added, “The COVID pandemic is the worst in a century, but it doesn’t mean another is about to happen… studies like this are a step in the right direction.”

The warning highlights the need for continued virus surveillance and preparation—not panic.