Researchers at the Wuhan Institute of Virology have identified a novel bat coronavirus, designated HKU5-CoV-2, which exhibits the capability to infect human cells by utilizing the same receptor as SARS-CoV-2, the virus responsible for COVID-19. This discovery underscores the potential for animal-to-human transmission, although no human infections have been reported to date.
The study, led by virologist Dr. Shi Zhengli and published in the journal Cell, reveals that HKU5-CoV-2 can bind to the human angiotensin-converting enzyme 2 (ACE2) receptor, facilitating its entry into human cells. This mechanism mirrors the cell entry process of SARS-CoV-2, suggesting a possible zoonotic threat. However, the researchers emphasize that the virus’s efficiency in infecting human cells is significantly lower than that of SARS-CoV-2, indicating a reduced immediate risk to public health.
HKU5-CoV-2 belongs to the Merbecovirus subgenus, which includes the Middle East Respiratory Syndrome coronavirus (MERS-CoV). Previous strains of HKU5 were identified in Japanese Pipistrellus bats in Hong Kong and were not known to infect humans. The current findings highlight the virus’s potential to cross species barriers, warranting vigilant monitoring. en.wikipedia.org
In laboratory experiments, HKU5-CoV-2 demonstrated the ability to infect human cells with high ACE2 expression, as well as cultured tissues mimicking human respiratory and intestinal organs. Despite this, the virus exhibits a lower binding affinity to human ACE2 receptors compared to SARS-CoV-2, suggesting that while cross-species transmission is possible, the likelihood of widespread human infection remains low.
The discovery has reignited discussions about the origins of SARS-CoV-2 and the role of the Wuhan Institute of Virology, which has been at the center of debates regarding the lab-leak theory of the COVID-19 pandemic. China has consistently refuted claims that SARS-CoV-2 originated from its laboratories. The identification of HKU5-CoV-2 underscores the importance of continued surveillance of coronaviruses in bat populations to preempt potential zoonotic events.
Financial markets have responded to the news, with shares of vaccine manufacturers experiencing fluctuations. Companies like Pfizer, Moderna, and Novavax saw stock movements following reports of the new virus, reflecting investor sensitivity to potential public health threats.
Experts advise caution but not alarm. Dr. Michael Osterholm, an infectious disease specialist at the University of Minnesota, suggests that the reaction to the study may be “overblown.” He points out that existing immunity in the population to similar SARS-like viruses, combined with the lower binding affinity of HKU5-CoV-2 to human receptors, reduces the likelihood of significant human adaptation and transmission.
The research team also identified potential therapeutic interventions. Certain antiviral drugs and monoclonal antibodies were found to be effective against HKU5-CoV-2 in vitro, offering a foundation for treatment strategies should the virus pose a future threat. Nonetheless, the primary focus remains on surveillance and prevention. reuters.com
This discovery serves as a reminder of the dynamic nature of coronaviruses and their ability to mutate and cross species barriers. Continuous monitoring of bat populations and other potential reservoirs is essential for early detection and prevention of possible outbreaks. While HKU5-CoV-2 does not currently pose an immediate threat comparable to COVID-19, the situation underscores the necessity for global collaboration in infectious disease research and preparedness.
