Almost three years after COVID-19 was detected in China, the country has reported cases of another zoonotic virus called Langya virus. According to reports, the new type of animal-derived Henipavirus has so far infected people in the Shandong and Henan provinces of China. Meanwhile, this new type of Henipavirus is also called Langya Henipavirus or the LayV.
According to scientists, it can cause severe illness in animals and humans, and at present, there are no licensed drugs or vaccines meant for humans.
What is Langya virus?
A zoonotic disease that spreads from animals to humans, the Langya virus was first detected in the northeastern provinces of Shandong and Henan in 2018 and was officially detected late last week. According to a study published in The New England Journal earlier this month, the new Henipavirus is associated with a febrile human illness and it was also found in shrews.
According to scientists, several other types of Henipavirus like Hendra, Nipah, Cedar, Mojiang and the Ghanaian bat virus are known to infect humans and cause fatal diseases. However, other related henipaviruses have been detected in bats, rodents, and shrews.
“During sentinel surveillance of febrile patients with a recent history of animal exposure in eastern China, a phylogenetically distinct henipavirus, named Langya henipavirus (LayV), was identified in a throat swab sample from one patient by means of metagenomic analysis and subsequent virus isolation. The genome of LayV is composed of 18,402 nucleotides with a genome organization that is identical to that of other henipaviruses,” the scientists stated in the study.
The study found that Langya is most phylogenetically related to Mojiang henipavirus, which was discovered in southern China. Meanwhile, the Langya virus is known to cause fever.
How Langya virus was found?
The newly detected Langya was discovered in eastern China during surveillance testing of patients who had fever along with a recent history of animal exposure. According to reports, it was identified and isolated from the throat swab sample of one of those patients.
The scientists who conducted the study pointed out that this newly discovered Henipavirus is associated with some febrile cases, and the infected people have symptoms including fever, fatigue, cough, anorexia, myalgia, and nausea. Wang Linfa, a Professor in the Programme in Emerging Infectious Diseases at Duke-NUS Medical School who was involved in the study said that the cases of Langya henipavirus so far have not been fatal or very serious, so there is no need for panic. However, it is still a cause for alert as many viruses that exist in nature have unpredictable results when they infect humans. Meanwhile, the findings of the study suggest that the shrew may be a natural reservoir of the Langya virus.
“Although human-to-human transmission has been reported for the Nipah virus,5 we found no obvious spatial or temporal aggregation of human cases or the assigned haplotypes on the basis of three common single-nucleotide polymorphisms,” the study revealed.
The researchers also pointed out that as there was no close contact or common exposure history among the patients, the infection in the human population may be sporadic. Moreover, the scientist highlighted the need for an in-depth investigation of associated human illness.
Symptoms of Langya Virus
According to the study, further investigation found that 26 out of 35 cases of Langya Henipavirus infection in Shandong and Henan provinces have developed clinical symptoms such as fever, irritability, cough, anorexia, myalgia, nausea, headache, and vomiting. While all 26 had a fever, 54% reported fatigue, 50% had a cough, and 38% complained of nausea. Also, 35% of the total 26, complained of headaches and vomiting.
The scientists also found that some infected patients have symptoms accompanied by abnormalities of “thrombocytopenia (35%), leukopenia (54%), impaired liver (35%) and kidney (8%) function”, the study noted.
What is the origin of this virus?
According to the study which analysed the infected patients, it is very much likely that the new virus has jumped from an animal to humans. Scientists have pointed out that it is highly possible that the shrew may be a natural reservoir of the Langya virus. Moreover, the study suspected shrews after conducting a serosurvey of domestic and wild animals. Among domestic animals, seropositivity was detected in goats and dogs.
Is there a possibility of human-to-human transmission?
Scientists have not yet presented any clear picture of the transmission of the Langya virus from human to human. The researchers who conducted the study have underlined that the sample size of their investigation is too small to determine human-to-human transmission. However, they emphasised that among the 35 patients infected by LayV, there was “no close contact or common exposure history”, which suggests that the “infection in the human population may be sporadic”. Moreover, the study noted that contact tracing of 9 patients with 15 close-contact family members revealed no close-contact LayV transmission.
Currently, there is currently no vaccine or treatment for Henipavirus and the only treatment is supportive care to manage complications. Meanwhile, some health experts told Financial Express.com that it’s “too early” to comment about human-to-human transmission.
“…Its too new and its difficult to predict the status of human-to-human transmission,” Dr. Dilip Gude, Senior Consultant Physician, Yashoda hospitals Hyderabad told Financial Express.com.
Moreover, the detection method will remain same as other zoonotic viruses like SARS-CoV-2, doctors told Financial Express.com.
“The detection method will remain same as other zoonotic viruses like SARS-CoV-2, will require a standardized nucleic acid testing method. As far as the treatment concerns, there is currently no vaccine or treatment for Lengya Henipavirus and the only treatment is supportive care to manage complications,” Dr. Namita Jaggi, Chairperson, Labs & Infection control, Artemis Hospitals Gurgaon told Financial Express.com.