Vietnam confirmed two new human cases of the H5N1 avian flu virus on Tuesday, raising the total number of bird flu cases reported in the country to four since the beginning of May, REPORTED DPA. The new patients are a 29-year-old man from Thanh Hoa province and a 28-year-old woman from Ha Nam province. The man was admitted to Thanh Hoa General Hospital on May 23 with bird flu-like symptoms. He recovered and was released from the hospital, but a sample of his bodily fluid has since tested positive for H5N1. The woman is being treated at Hanoi's Hospital for Tropical Diseases, and is in serious condition. Doctors have placed her on a mechanical respirator. On Monday, one of the two patients diagnosed earlier with avian flu was released from Hanoi's Bach Mai Hospital, after making a full recovery.