Chinese health authorities have confirmed the world's first human infection with H10N3 avian influenza in a 41-year-old man from Zhenjiang. While this strain primarily affects birds, officials emphasize the risk of widespread human transmission remains "extremely low."
Typically circulating among birds, H10N3 has now crossed into humans for the first time, according to China's National Health Commission. The patient was hospitalized in late April with worsening fever symptoms. Genetic analysis by the Chinese Center for Disease Control and Prevention (CDC) confirmed the diagnosis days ago.
"The risk of large-scale spread is extremely low," the commission stated, describing it as an "accidental interspecies transmission."
Avian flu strains have sparked human outbreaks in rare instances. For example, H7N9 caused over 300 deaths in 2016-2017 with a case fatality rate of about 40%. Historical evidence also links the 1918 H1N1 pandemic strain to birds, challenging earlier theories of human-swine origins.
The Chinese CDC conducted extensive surveillance in Jiangsu Province, including close contacts of the patient, but no further infections have been found. The man is now stable and expected to be discharged soon.
Experts like Filip Claes from the UN's Emergency Center for Transboundary Animal Diseases stress the need for detailed genetic sequencing to compare this human strain with avian samples. H10N3 is uncommon even in birds, with roughly 160 cases documented worldwide over the past 40 years, mostly in waterfowl and wild birds. It has not been found in chickens, and the infection source for this patient remains unclear.
Earlier this year, Russia reported the first human cases of H5N8 avian flu among seven poultry workers, though no human-to-human spread was observed.
