Two more people have been infected with bird flu in Vietnam, bringing to four the number of new human cases since last month, health officials and state media reports said on Wednesday.
Two farmers, a man from Thanh Hoa province and a woman from Ha Nam province, tested positive for H5N1, senior health official Nguyen Huy Nga told the national bird flu committee, state media said.
Communist Vietnam, once the country worst hit by the disease, has won praise for containing earlier bird flu outbreaks, but the virus has come back strongly this year, hitting scores of poultry farms especially in the north.
Vietnam's first human case of avian influenza since November 2005, a 30-year-old man, was released on Monday from a Hanoi hospital, while a second male patient, 19, who fell ill in late May, is still undergoing treatment.
Media reports and health officials on Wednesday confirmed two new cases, although none of the four reported infections has yet been officially confirmed by the World Health Organisation (WHO), which keeps a global tally of cases.
"A female H5N1 patient is now under treatment at our hospital," said a physician at the Tropical Diseases Institute in Hanoi about the Ha Nam province patient. "She is in a serious condition."
The Tuoi Tre (Youth) daily said four other patients at the hospital were suffering from pneumonia and being treated as possible bird flu cases.
In the Thanh Hoa provincial hospital, south of Hanoi, senior official Do Thi Tuyet said a man from the province had been admitted on May 23 with symptoms of H5N1 but had been discharged on June 3.