An international team of scientists is tracking a newly-identified, potentially dangerous virus that has jumped from animals to humans to infect at least 35 people in northeast China.
The Langya henipavirus, also called "Langya" or "LayV," was first detected in 2018 in a 53-year-old farmer who sought treatment for a fever at a hospital in the northeastern Chinese province of Shandong. A subsequent investigation, conducted between 2018 and 2021, revealed 34 more cases of infection in Shandong and the neighboring province of Henan.
As there is yet no evidence of human-to-human transmission and the vast majority of those infected are farmers, the researchers have hypothesized that the outbreak may be the result of viral transmission from animals to humans — an event known as zoonotic spillover.
The newly-named virus, whose discovery is detailed in an Aug. 4 study published in the New England Journal of Medicine (opens in new tab), belongs to the henipavirus family, the same family of viruses as the deadly Nipah and Hendra viruses — the former having an estimated case fatality rate between 40% and 75%, according to the World Health Organization (opens in new tab) (WHO). The latter virus rarely infects people but has an estimated case fatality rate of 57%, according to the Centers for Disease Control and Prevention (opens in new tab) (CDC). There is no approved vaccine against any of the henipaviruses for humans.
Thankfully, Langya infections have so far been comparatively mild, with patients presenting with symptoms that include fever, cough, fatigue, headache, appetite loss, vomiting and muscle aches. Several patients also developed signs of kidney and liver damage, but there have been no reported deaths thus far.
"At this stage, LayV doesn't look like a repeat of Covid-19 at all, but it is yet another reminder of the looming threat caused by the many pathogens circulating in populations of wild and domestic animals that have the potential to infect humans," Francois Balloux, a professor of computational biology systems at University College London who was not involved in the study, wrote on Twitter (opens in new tab) on Aug. 9.
The study's scientists found that, of 25 species of wild animals investigated, shrews tested positive for the virus most frequently, with 27% of the 262 small, mole-like animals surveyed discovered to have the virus's genetic material in their tissues and urine. This makes shrews a potential natural reservoir for the virus, which was also present in some domestic animals, including 5% of the dogs and 2% of the goats surveyed.
Although there has been no evidence of human to human transmission, the researchers say they are unable to rule it out.
"Contact tracing of nine patients with 15 close-contact family members revealed no close-contact LayV transmission, but our sample size was too small to determine the status of human-to-human transmission," the researchers wrote in the paper.
Scientists who study zoonotic diseases have been warning that spillover events such as this one, and the one that led to the COVID-19 pandemic, will become more likely as deforestation, urbanization and the shrinking of natural habitats due to human-caused climate change continue. In fact, three out of four new or emerging infectious diseases in humans have come from animals, according to the CDC (opens in new tab), and 500,000 or more viruses already have spillover potential, Live Science previously reported.
Originally published on Live Science.