The first sample of Langya virus was detected in late 2018 from a farmer in Shandong province who was seeking treatment for fever. About about over a two-year period, another 34 people were infected in Shandong and neighboring Henan, the vast majority being farmers.
Genetic sequencing of the virus then showed that the pathogen is part of the henipavirus family, which has five other known viruses. Two are considered highly virulent and are associated with high case fatality rates, according to the US Centers for Disease Control and Prevention. But none of Langya’s patients died, according to the study.
Of the 35 patients, 26 were found to be infected only with Langya virus. All 26 had a fever, with around half showing fatigue, decreased white blood cell count and cough. More serious symptoms include impaired kidney and liver function.
The researchers also tested 25 species of small wild animals for the Langya virus. Its genetic material was ‘mostly detected’ in shrews, leading the team to suggest small mammals are a “natural reservoir” of the virus.
Disease surveillance has not indicated common sources of exposure to infected people, nor have they been in close contact with each other, suggesting that human infection may have occurred. “sporadically,” the researchers wrote.
Francois Balloux, a professor of computational systems biology at University College London who was not involved in the study, said the Langya virus does not appear to “look like a repeat of Covid-19 at all”. He noted on Twitter that the new virus is much less deadly than other henipaviruses and “probably does not spread easily from human to human”. .
But this finding serves “yet another reminder of the looming threat caused by the many pathogens circulating in wild and domestic animal populations that have the potential to infect humans,” Balloux added.
Viruses that are transmitted from animals to humans are not uncommon. According to scientists, around 70% of emerging infectious diseases in humans are zoonotic in origin, and nearly 1.7 million undiscovered viruses may exist in mammals and birds. Hendra and Nipah viruses, two henipaviruses with high mortality rates, can be contracted through close contact with sick horses, pigs and bats.
Scientists who study zoonotic diseases warned even before the coronavirus pandemic that practices such as the unregulated wildlife trade, deforestation and urbanization have brought people closer to animals, increasing the risks of viral spread.
Karin Brulliard contributed to this report.
