GUIYANG - A total of 110 people who had close contact with two patients contracted avian influenza H5N1 in Southwest China's Guizhou province earlier this month have been released from quarantine, local health authorities announced on Sunday.

Two residents of the provincial capital of Guiyang were reported to have contracted the H5N1 virus on February 8. The health authority put 110 people who had close contact with the two patients under quarantine, according to the provincial government's emergency response office.

They were released as no abnormal symptoms were discovered.

One patient, a 21-year-old woman, died of multiple organ failure on Wednesday. The other patient, a 31-year-old man, is still receiving medical treatment.

No new avian influenza H5N1 cases have been reported, according to the office.

The human-transmissible form of avian influenza, also known as bird flu, is an acute respiratory infectious disease mainly caused by the deadly H5N1 virus subtype. Main symptoms include high fever and pneumonia.

Human infections of bird flu are usually caused by the transmission from poultry to humans. There have been no reported cases of sustained human-to-human transmission.