Two test positive for bird flu in China

China's health ministry reported two human cases of H5N1 bird flu on Sunday in Guiyang, China.

Both patients are critically ill, according to state media.

A 31-year-old man and a 21-year-old woman developed symptoms on February 3 and February 2, respectively. The two patients tested positive for the H5N1 virus on Sunday, Xinhua reports.

"They are in critical condition and medical workers are carrying out emergency treatment," the ministry said, according to Xinhua. "No epidemiological connections have been found between the two cases."

An investigation into the cases did not find that the two had contact with fowl prior to falling ill. Close contacts with the two patients were put under medical observation, though none of them exhibited any symptoms of illness.

Human-infected highly pathogenic avian influenza virus is an acute respiratory infectious disease caused by the deathly H5N1 subtype virus. Major symptoms include pneumonia and high fever. There are no reported outbreaks of sustained human-to-human transmission of the virus, Xinhua reports.

China is not the only country facing such infections. Cambodia recently reported its fifth bird flu death of 2013. The five-year-old victim was in contact with poultry prior to contracting the disease. Bird flu was confirmed at a poultry farm in Kathmandu on Sunday and the Department of Livestock Service culled chickens and destroyed poultry feed in response, the Himalayan Times reports.