Six more people in China have been confirmed as infected with the new H7N9 strain of bird flu and one of them has died, the World Health Organization (WHO) said Monday. Three of the other five patients are in either a serious or a critical condition in hospital, while the remaining two have mild symptoms, the U.N. health agency said in a disease outbreak update. H7N9 bird flu emerged last year in China and has infected roughly 150 people so far there and in Taiwan and Hong Kong, killing at least 46 of them. The latest death was a 38-year-old man from China's Fujian Province who became ill with H7N9 on January 3, was admitted to hospital on January 8, and died two days later. He had underlying illnesses, including tuberculosis and pneumoconiosis. China's state news agency Xinhua reported another death from H7N9 in the southwestern Guizhou province Monday, but it has not yet been confirmed by the WHO. A 65-year-old man infected with H7N9 also died in Hong Kong, the government said Monday. The WHO reiterated that there is no evidence yet of any easy or sustained person-to-person transmission of the strain, and that the source of the human infections is still under investigation.