One of Taiwan's best regarded hospitals transplanted organs from an HIV carrier into five patients, a hospital official said Monday, in what appears to be one of the most egregious examples of medical negligence in the island's modern history. The five are now being treated with anti-AIDS drugs, said the official at National Taiwan University Hospital in Taipei. The official spoke on condition of anonymity because she is not authorized to deal with the media. In a posting on its website over the weekend, the hospital said the mistake occurred because a transplant staffer believed he heard the English word "non-reactive" on the donor's standard HIV test, which means negative, while the word "reactive" was actually given. The hospital added that the information on the test result was given over the telephone and was not double-checked, as required by standard operating procedures. "We deeply apologize for the mistake," the hospital said.