An international research team from Japan, the United States, Australia, and Belgium has identified a new virus similar to Covid-19 in a species of moustached bats in Brazil. This discovery has raised alarm regarding a possible spillover that could lead to a new disease outbreak.
The scientists from Osaka University and the University of Sydney detected the virus, named BRZ batCoV, in the Pteronotus parnellii species, a small insect-eating bat characterized by distinctive facial hair tufts. Despite the bat being a common species in South America, experts express concerns that the virus may have been spreading unnoticed for an extended period.
In a pre-print study published on BioRxiv, the researchers stated, “We identified a full-length genome of a novel bat CoV (BRZ batCoV) from a Pteronotus parnellii bat sampled in Brazil that is phylogenetically distinct from known betacoronaviruses.” They further analyzed the evolutionary lineage of the virus, concluding that it is sufficiently unique to be classified as a new subgenus.
Significantly, the spike protein of this newly discovered coronavirus features a functional furin cleavage site at the S1/S2 junction, containing a distinct amino acid sequence motif (RDAR) that varies from that of SARS-CoV-2 (RRAR) by just one amino acid. This cleavage site is critical in determining host range, infectivity, and the potential for cross-species transmission, being present in surface proteins of several RNA viruses, including the highly pathogenic avian influenza and Ebola viruses.
Moreover, the research indicates that BRZ batCoV is more closely related to Middle East Respiratory Syndrome (MERS) viruses than to Covid-19. MERS, often referred to as camel flu, has a lower transmission rate compared to Covid-19 but is significantly deadlier, with a mortality rate of approximately one-third among those infected.
Despite the alarming potential for this new virus, scientists emphasize that there is currently no evidence suggesting that BRZ batCoV can infect humans or spread beyond bat populations. The researchers noted that this discovery offers valuable insights into the evolutionary potential and zoonotic risks associated with BRZ batCoV, underscoring the role of bats as reservoirs for genetic innovations that could lead to future zoonotic outbreaks.
