Khaberni - Researchers in China have raised increasing concerns about the potential spread of a troubling flu variant capable of transmitting from cattle to humans.
A recent study showed that a virus known as influenza D (IDV) is undergoing mutations that might enable it to cross the animal barrier and spread among humans.
A team from the Changchun Institute of Veterinary Research led the study, which focused on a specific strain of the virus known as D/HY11, first detected in cattle in northeastern China in 2023.
The results indicated that this variant grows and multiplies in human airway cells and in various animal tissues, suggesting its potential adaptation to the human environment.
During the experiments, it was found that the virus could be transmitted through the air among animals, including rodents and ferrets—a standard model for studying human influenza transmission—without any direct contact, suggesting the possibility of airborne transmission among humans in the future.
Blood tests showed that about 74% of the population in northeastern China have antibodies against the virus, indicating widespread exposure, while the rate was 97% among those who showed respiratory symptoms. However, it has not yet been determined whether the infection is transmitted from human to human or if the current cases are due to direct transmission from animals.
The research team confirmed in their study that: "An outbreak of influenza D virus is likely to have become a persistent issue affecting both cattle and humans."
The researchers tested the virus on cells from humans and animals to simulate the natural airway, finding that it infects all of them and replicates with high efficiency. The analyses showed that the polymerase of the D/HY11 virus strain exhibits increased activity, a characteristic often associated with a higher capacity for spread among mammals. (Polymerase is the "molecular copying machine" used by the virus or cell to replicate and produce new copies of its genetic material)
As for treatment, the virus was sensitive to modern drugs like "baloxavir," but resistant to common drugs such as "Tamiflu," raising questions about the effectiveness of current treatments if the virus becomes a human pathogen.
Retroactive serum analyses (2020–2024) suggested that the influenza D virus might have been spreading in northeastern China since 2020 without being officially detected, given the absence of routine tests to detect it worldwide, which reinforces concerns about the silent spread of new virus strains.
The study results were published in the journal Emerging Microbes & Infections, while international health monitoring networks have confirmed they are closely following the virus’s developments, amid increasing global concerns about the recurrence of pandemic scenarios.
