In people, the virus caused symptoms including fever, fatigue, cough, loss of appetite and muscle aches. All of the people infected had a fever, the scientists said. The virus was the only potential pathogen found in 26 of the 35 people, suggesting that “LayV was the cause of febrile illness”.

There have been no deaths from LayV to date. Prof Wang Linfa of the Duke-NUS Medical School, a co-author of the NEJM paper, told the state-run Global Times that the LayV cases had “not been fatal or very serious” so far and that there was “no need for panic”.

It was still unclear whether the virus can be transmitted between people, researchers said. Most of the 35 cases were in farmers, and other infected individuals included factory workers. “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 found.