Über einen Zeitraum von drei Jahren haben sich 35 Menschen in China mit einem neu entdeckten Virus infiziert. Der Erreger mit dem Namen Langya-Henipavirus, kurz Live, wurde bisher nur in Personen mit Tierkontakt nachwiesen. Die bekannten Infektionen traten in den ostchinesischen Provinzen Shangdong und Henan auf. Das berichtet ein internationales Forschungsteam um Xiao-Ai Zhang vom chinesischen Institut für Mikrobiologie und Epidemiologie in Peking im Fachmagazin »New England Journal of Medicine« .
At the end of 2018, the researchers discovered the pathogen for the first time in the throat smear of a 53-year-old woman with a fever and previous contact. Then they tested patients in three Chinese hospitals for the Henipavirus. By 2021, they were able to prove it in 35 feverish people who had come into contact with animals last month. Those affected reported about flu symptoms such as fatigue, cough, muscle pain, nausea and vomiting, right down to pneumonia. In some cases, the functions of the liver and kidneys were impaired; Furthermore, the immune cells in the blood of some affected people were reduced. No deaths were known. The researchers could not clearly prove that the Langya virus was the trigger for the symptoms. According to their assessment, however, this speaks that 26 of the 35 patients were not infected with any other pathogens at the time of the disease. In addition, most of those affected had antibodies against the virus after surviving infection.
Exactly how the virus spreads is not certain. There were no indications of direct transmission from person to person; the known affected persons were not in contact with each other and close family members were not infected either. The infections were therefore likely to have occurred sporadically, the authors of the study write. They assume that the pathogen has been transmitted from animals to humans: the researchers were also able to detect the same Langya henipavirus in shrews. The small mammals may serve as a reservoir for the pathogen.
Close relationship with zoonotic pathogens
Henipaviruses belong to the family of paramyxoviruses, which also includes measles and mumps viruses. Representatives of this family are characterized by the fact that they affect the respiratory tract and are usually transmitted by droplet infection. However, it is not yet known whether LayV can be transmitted in the same way. The closest relative of the Langya virus is the Mojiang virus from the same virus family. It is also one of the zoonotic pathogens: In 2012, it was first detected in rats in southern China.
Zoonoses are not uncommon and not always worrying: As researching around Peter Daszak in the specialist journal "Nature Communications", tens of thousands of people with unknown coronaviruses are pending every year - often without noticing anything. The pathogens occur especially in bats. However, if there were enough infections at once, the pathogens could suddenly spread strongly in human populations, the scientists report. In order to determine the risk of such a transmission event, Daszak and his team have created a hotspot card for Southeast Asia. It marks the areas in which a particularly large number of infected bats meet large crowds and may pass on the viruses. This hotspot analysis could help to keep an eye on the coronaviruses and to quickly recognize increased virus transmissions-and ultimately prevent another pandemic.
The newly discovered Langya henipavirus is also under increased observation at first. Further investigations are now important in order to be able to better understand the pathogen and the infectious disease triggered by it, Zhang and his team conclude in their work.
