What are Merbecoviruses?
A recent study published in Nature Communications by researchers from Washington State University (WSU), the California Institute of Technology and the University of North Carolina, has raised concerns about a group of bat viruses closely related to the deadly Middle East Respiratory Syndrome Coronavirus (MERS-CoV). Scientists warn that a specific subgroup of these viruses, known as HKU5, is showing signs of being just one small mutation away from being able to infect humans. This raises serious concerns about the potential for these viruses to spill over from animals to people, potentially triggering the next global pandemic.
Merbecoviruses are a subgenus of coronaviruses that includes MERS-CoV, which was first identified in 2012 and has a mortality rate of approximately 34%. These viruses primarily infect bats but have the potential to jump to humans, as evidenced by MERS-CoV. While most merbecoviruses have been studied to some extent, the HKU5 subgroup has received limited attention until now.
The discovery of HKU5's potential to infect humans
The recent study focused on understanding how HKU5 viruses infect host cells. The researchers found that while most merbecoviruses appear unlikely to pose a direct threat to humans, HKU5 viruses possess concerning traits. Specifically, HKU5 viruses were shown to use a host receptor known as ACE2, the same receptor used by the more well-known SARS-CoV-2 virus that causes COVID-19. However, HKU5 viruses, for now, can only use the ACE2 gene in bats and do not use the human version nearly as well.
This discovery is significant because it suggests that with just a small mutation, HKU5 viruses could potentially infect humans. The researchers used artificial intelligence to model how the HKU5 spike protein binds to ACE2 at the molecular level, which could help provide a better understanding of how antibodies might block the infection or how the virus could mutate.
The risk of zoonotic spillover
Zoonotic spillover refers to the process by which a virus jumps from animals to humans. This has been the source of several past pandemics, including SARS, MERS, and COVID-19. The ability of HKU5 viruses to bind to the ACE2 receptor in bats and potentially in humans raises the possibility of zoonotic spillover.
The study also highlighted that one HKU5 virus in China has already been documented to have jumped into minks, showing there is potential for these viruses to cross species barriers. While there is no evidence that HKU5 viruses have infected humans yet, the potential is there, and that makes them worth monitoring.
The role of AI in virus research
The researchers used a program called AlphaFold 3 to model how the HKU5 spike protein binds to ACE2 at the molecular level. This approach allowed them to generate accurate predictions in minutes, a process that traditionally required months of lab work and specialized equipment. The results matched those recently documented by a research team that used traditional approaches.
This use of artificial intelligence in virus research is a significant advancement, as it allows scientists to quickly assess the potential risks of various viruses and develop strategies to counteract them.
While there is no immediate cause for alarm, the discovery that HKU5 viruses can bind to the human ACE2 receptor is a concerning development. The potential for these viruses to mutate and infect humans underscores the need for continued surveillance and research into bat coronaviruses. By understanding how these viruses function and how they might evolve, scientists can better prepare for potential future pandemics.
As we have seen with past pandemics, the jump of a virus from animals to humans can have devastating consequences. Therefore, it is crucial to monitor these viruses closely and take proactive measures to prevent potential outbreaks. The recent study serves as a reminder of the ever-present threat of zoonotic diseases and the importance of vigilance in the face of emerging infectious diseases.
Source: Times of India.
