HKU5 coronavirus is unlikely to lead to a pandemic, but to prevent future coronavirus pandemics it is important to support scientific research, emerging disease surveillance, and vaccine and medication development.
Main points:
- HKU5-CoV-2 did not infect laboratory cells under controlled conditions as well as the virus that causes COVID-19
- Current antivirals and monoclonal antibodies inhibited HKU5-CoV-2 supporting additional testing for possible use in human infections
- Support for scientific study of viruses, emerging disease surveillance, and development of vaccines is crucial to combat future pandemics
A new article from Zheng-Li Shi’s lab (famous for studying bat coronaviruses) came out this month on a coronavirus collected from bats in China (HKU5-CoV-2). Unlike its previously studied relative (HKU5-CoV-1), “HKU5-2” has a greater ability to bind to ACE-2, a receptor that exists in many different species. The concern is that like the virus that causes COVID-19 (SARS-CoV-2), HKU5-2 has the ability to infect many different animal and human species, meaning it could lead to human-to-human transmission.
HKU5 is a coronavirus that belongs to the “MERS group” of coronaviruses (see image below). While some coronaviruses can be incredibly deadly (MERS, SARS, SARS-CoV-2), others spread through the population without serious damage. HKU1, another coronavirus, circulates every year in the US. It doesn’t cause severe disease but can lead to missed days of school and/or work.

Simplified coronavirus family tree (adapted from Wu and Zhao, 2021)
The ability to bind well to ACE-2 is one of five well-known ways coronaviruses, including the virus that causes COVID-19, attach to cells, making them more infectious to humans and mammals.

Source: London School of Hygiene and Tropical Medicine
The circulation of coronaviruses with the ability to infect humans is a very real threat and something that concerns biosecurity experts (people who study infectious disease threats). Bats are known to carry different strains of coronavirus, and likely carried the ancestors of SARS, MERS, and the COVID-19 virus.
In 2017, Zheng-Li Shi’s lab found several strains of coronavirus with the ability to use the ACE-2 receptor for cell entry in just one cave. When these viruses spill over to other animals or humans, this can lead to spread or mutations that make it easier for the virus to infect humans. Similar viruses to “HKU5-2” were recently found in farmed minks, meaning the virus likely has already moved to another species.
🙌 What shows promise:
- The virus that causes COVID-19 may bind better to ACE-2 than this strain of HKU5-2, meaning it’s possible HKU5-2 is less infectious and/or severe.
- Lab studies performed in this new paper showed several treatments with antiviral activity against HKU5-2, but still would need to be tested on actual patients.
✅ What can we do?
- Support scientists in the study of these viruses and the development of therapeutics (medications) and vaccines. Scientists are currently working on a pan-coronavirus vaccine that could potentially limit a future coronavirus pandemic.
Stay well. Stay Nerdy.
Love,
Those Nerdy Girls
Resources:
Gavi News – A new coronavirus has just been discovered. Should we be worried?
London School of Hygiene and Tropical Medicine – Expert comment – new bat coronavirus discovery
New York Times Opinion – Recent Virus Research Should Raise the Alarm
CDC – CDC common coronavirus dashboard [archived link]
Cell – Cell paper on HKU5-CoV-2