The World Health Organization said that such an infection was “a vivid reminder that the threat of an influenza pandemic is persistent.”

Influenza viruses differ from coronaviruses, and the World Health Organization is working with the Chinese government to monitor the case, according to a statement from the W.H.O. division in Beijing.
The man began feeling feverish at the end of April and was hospitalized on April 28, the Chinese government statement said. On May 28, genome sequencing by the Chinese Center for Disease Control and Prevention determined that he had been infected with H10N3.
The government announcement did not say how the man had been infected, and the W.H.O. said the source of infection was still unknown. The mans condition has stabilized, and he is ready to be discharged, the government said.
Professor MacIntyre said that people who are usually infected by avian viruses are those who are in prolonged close contact with the birds, such as poultry handlers.
The W.H.O. said that H10N3 had been detected periodically in birds in live bird markets as early as 2002, but the virus is unlikely to kill birds or lead to many signs of illness.