New henipaviruses discovered in bats

Researchers have identified new viruses, bacteria and parasites among bats in orchards in China’s south-west — with two of the viruses being closely related to the deadly Nipah and Hendra viruses. The discovery has been reported in the journal PLOS Pathogens by Yun Feng of the Yunnan Institute of Endemic Disease Control and Prevention and colleagues.

Bats are natural reservoirs for a wide range of microorganisms, including many notable pathogens that have been transmitted to humans. However, a full survey of the diverse array of viruses, fungi, bacteria and parasites that infect bats has been lacking, with most previous studies focusing on bat faeces rather than the animals’ organs.

In the new study, researchers looked inside the kidneys of 142 bats from 10 species, collected over four years across five areas of China’s Yunnan province. Using advanced genetic sequencing, the team found 22 viruses — 20 of them never seen before — along with a novel protozoan parasite, tentatively named Klossiella yunnanensis, and two highly abundant bacterial species, one of which is a newly discovered species (Flavobacterium yunnanensis).

Two of the most concerning finds were new henipaviruses — the same genus as Nipah and Hendra viruses, which can cause severe brain inflammation and respiratory disease in humans and are known for their high fatality rates. Worryingly, the viruses were found in fruit bats living near orchards close to human villages — and since henipaviruses can spread through urine, there is some concern about contaminated fruit and the risk of these viruses jumping to humans or livestock.

“By analysing the infectome of bat kidneys collected near village orchards and caves in Yunnan, we uncovered not only the diverse microbes bats carry, but also the first full-length genomes of novel bat-borne henipaviruses closely related to Hendra and Nipah viruses identified in China,” the study authors said.

“These findings broaden our understanding of the bat kidney infectome, underscore critical zoonotic threats, and highlight the need for comprehensive, full-spectrum microbial analyses of previously understudied organs to better assess spillover risks from bat populations.”

Just weeks later, CSIRO scientists published the discovery of their own new virus in Australian flying foxes, which they have named Salt Gully virus. Described in the journal Emerging Infectious Diseases, the novel virus was found in bat urine samples collected in Queensland, and is similarly a henipavirus.

The researchers were able to isolate and grow Salt Gully virus in CSIRO’s Australian Centre for Disease Preparedness (ACDP) high containment laboratory, which allow teams to work safely with animal and zoonotic diseases while keeping them securely contained. Jennifer Barr, an experimental scientist at the ACDP, said henipaviruses are recognised by the World Health Organization as priority pathogens for research, and the discovery increases knowledge of this important virus group.

“Although Salt Gully virus is new to science, there’s no cause for public alarm,” Barr said.

“We’ve detected Salt Gully virus in bat samples dating back to 2011, which shows it’s been circulating in nature for over a decade without any evidence of it causing illness in animals or humans.”

According to Barr, the discovery provides a foundation for further research into how the virus compares with Hendra and Nipah. She stated, “Early findings show Salt Gully virus does not rely on the same cell receptors as Hendra or Nipah viruses, suggesting that the infection process will be different. As a result, we can’t predict whether it will result in future disease outbreaks in humans or animals.”

By understanding these viruses, the researchers say they can better prepare for potential outbreaks. Barr explained, “Now that we’ve identified the virus, diagnostic tests can be developed. This means if a spillover from bats and disease outbreak were to occur, we’d have the tools to detect this virus earlier — enabling timely measures to prevent further spread.”

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