20 previously unknown viruses linked to human diseases found in Chinese bats

By Karoline Kan

Scientists have discovered 20 previously unknown viruses in bats from China’s Yunnan province, including two closely related to the deadly Nipah and Hendra viruses, raising fresh concerns about the risk of animal pathogens infecting people.

The viruses related to Nipah and Hendra came from fruit bats caught near orchards close to villages, places where people and farm animals are more likely to come into contact with wildlife.

The findings, published Tuesday in the journal PLOS Pathogens, underscore how much remains unknown about the microbes carried by bats — animals that serve as natural hosts for some of the world’s most dangerous pathogens. Scientists have long warned that climate change, farming expansion, and urbanization are bringing animals and people into closer contact, increasing the likelihood of new viruses emerging and sparking outbreaks, as seen with SARS, Ebola, and Covid-19.

“This study highlights that we know very little about the viruses that infect bats and those that exist in our world more generally,” said Tim Mahony, director of the Centre for Animal Science at Australia’s University of Queensland, who wasn’t part of the study.

The research involved scientists from China and the University of Sydney, who examined the kidneys of 142 bats collected over four years in Yunnan. They identified 22 viruses in total, 20 of which hadn’t been previously recorded. Among them were two henipaviruses closely related to Nipah and Hendra, which can cause fatal brain inflammation and respiratory illness in people, with mortality rates as high as 75%.

Credit: Bloomberg

The team also reported two new bacterial species and one previously unknown parasite. While most studies of bat viruses focus on feces, the researchers looked at kidney tissue, which plays a role in virus shedding through urine — a lesser-studied but potentially important route of transmission.

The two new henipaviruses were found in fruit bats living near agricultural areas, where urine from bats may contaminate fruit that’s eaten by people or livestock. The findings “underscore critical zoonotic threats,” the study authors wrote, adding that the potential for such viruses to infect humans or farm animals needs urgent attention.

Despite the potential implications, one of the study’s corresponding authors declined to speak in detail, telling Bloomberg by email that “the topic is quite sensitive” due to how politically charged it has become.

Experts say the discovery is scientifically significant, though it’s still too early to know how dangerous the new viruses might be.

“This discovery basically further confirms the diversity of bat viruses in general and henipaviruses in particular,” said Linfa Wang, professor at the Programme in Emerging Infectious Diseases at Duke-NUS Medical School. “My overall assessment is that we need to watch closely, but not be overly concerned at the present time.”