Dozens of confirmed cases in China
- More than 30 people in China have been sickened by a newly identified virus.
- Symptoms of Henipavirus Langya, or LayV, include fever, fatigue, cough, muscle aches, pain, nausea, headache, and vomiting.
- Researchers believe the virus spread from animals to humans, in this case through shrews.
- So far, none of the infected people have died.
- Experts have also found no evidence that the virus can be transmitted between people.
An international team of scientists have identified a new virus, called LayV, which they believe was potentially transmitted to humans by shrews – another example of a
However, none of those infected with the new virus have died. Additionally, the scientists say there is no evidence of viral spread among people, although they admit their sample size was too small to be certain.
The researchers – based in China, Singapore and Australia – detailed their discovery on August 4 in The New England Journal of Medicine.
The researchers identified LayV during routine follow-up of patients for potential zoonotic diseases at three hospitals in eastern China between 2018 and 2021.
The first patient was a 53-year-old woman who went to hospital in December 2018 with fever, headaches and other symptoms. The researchers sequenced the genome of the virus from a throat swab taken from the woman.
During the study period, researchers identified 35 other people infected with LayV. Of these, 26 were infected only with LayV (no other viruses). All of the people in the study had a recent history of exposure to animals.
Fever was the most common symptom in people infected with LayV, occurring in all patients. Other symptoms included fatigue, cough, muscle aches, pains, nausea, headache and vomiting.
Some people also had low blood platelet counts, low white blood cell counts, impaired liver function, or impaired kidney function.
None of the patients in the study died from illness caused by LayV infection.
Although the risk from the virus appears to be low, Anthony P. Schmitt, PhD, professor of molecular virology at Pennsylvania State University in University Park, Pennsylvania, pointed out that fewer than 40 people were infected. These may therefore not be representative of the entire population.
“If the virus were to cause a larger outbreak affecting hundreds or thousands of people, some with pre-existing conditions, it’s possible we’ll see cases of more severe disease,” he said.
To determine the potential origin of LayV, the researchers tested samples from domestic goats, dogs, pigs, cattle and 25 species of small wild animals in the villages of infected patients.
They found LayV antibodies in a small number of goats and dogs (5% or less of animals tested). Among wild animals, they found LayV genetic material (RNA) “predominantly” in shrews (27% of animals tested).
“[This finding] suggests that the shrew could be a natural reservoir of LayV,” the researchers said. However, it is unclear whether people were infected directly by the shrews or by an intermediary animal.
Dr. Benhur Lee, professor of microbiology at the Icahn School of Medicine at Mount Sinai in New York, wrote on Twitter that “the evidence is strong that LayV [has] sporadically transmitted to humans by shrews, causing pneumonia and flu-like symptoms.
Also, while “no deaths have been reported and there is no evidence of further human transmission…continued surveillance is important,” he said.
Of the 35 people infected with LayV since 2018, none of the cases appear to be linked, researchers said in the paper.
They also did
However, the researchers said the number of infected patients and close contacts was “too small” to determine whether LayV could spread between people.
Schmitt said that because the 35 infections in this study occurred over multiple years and there is no evidence of person-to-person transmission, “there does not appear to be any immediate cause for alarm.”
In the long term, it’s another story.
The study results suggest that people come into contact with animals infected with LayV and sometimes become infected themselves.
“Each time this happens, the virus presumably has a chance – maybe only a small chance, but a chance nonetheless – to adapt within its new human host and become more adept at transmitting to other people. other people,” Schmitt said.
“The concern is that with enough chance we will end up having bad luck and a virus will adapt in the right way to cause a serious epidemic,” he added.
The spread of viruses from animals to humans – who, we often forget, are also animals – is nothing new. It’s been going on as long as people have been around.
However, there are fears that climate change, unregulated wildlife trade, deforestation and urbanization will increase
Schmitt said it’s unclear if these types of overflow events are increasing or if we’re just getting better at detecting them.
“In the past, when someone got sick from [of one of these transmissions], it would remain a ‘mystery disease’,” he said. “Now sometimes we solve the mystery, and those fallouts that were hidden come to light.”
LayV belongs to a family of viruses known as
Two other henipaviruses known to infect humans are more closely related to LayV: Hendra virus and Nipah virus. These cause severe flu-like illness that is often fatal, according to the US Centers for Disease Control and Prevention.
Fruit bats are the natural host for both viruses, but they can also infect other animals. People can contract Hendra virus through contact with infected horses or with the tissues or body fluids of infected horses.
Nipah virus can be transmitted to humans from infected bats or pigs or through exposure to bat urine. Person-to-person transmission has been reported with Nipah virus, but not with Hendra virus.
However, the researchers said LayV is most closely related to Mojiang henipavirus, a rat-borne virus that was first identified in southern China in 2012 after three miners developed severe pneumonia. and died.
Lee and his colleagues