A 21-year-old woman has been infected by both HIV and bird flu, the first such case in Vietnam, health officials said Thursday.

The Health Ministry said two other patients have been diagnosed with the H5N1 virus in the northern provinces of Ha Tay and Hung Yen between April 2 and 8 but no deaths were reported.

The latest findings brought to 41 the total number of patients with bird flu in Vietnam since December 2004, 16 of whom have died, the ministry said in a statement.

Nguyen Van Thich, head of the Center for Preventive Medicine in the northern province of Quang Ninh, said the woman, the first to be diagnosed with both bird flu and HIV in Vietnam, used to work at a hairdresser’s shop. She was hospitalized in late March with fever and coughing.

“She is still very weak,” he told Reuters, adding that the woman has been treated at a provincial hospital.

Quang Ninh province bordering China has one of the highest number of HIV carriers in Vietnam, most of them drug addicts and prostitutes.

Vietnam has reported 68 human infections of the H5N1 virus since the disease first hit Asia in late 2003, killing 36 Vietnamese.

Twelve Thais and three Cambodians have also died of the virus that the World Health Organization says has the potential to mutate into a form that could pass easily between humans and cause a pandemic in which millions could die.

Doctor Nguyen Tran Hien, director of the National Institute of Hygiene and Epidemiology, was quoted Thursday by state media as saying Vietnam has taken nearly 1,000 blood samples from the patients, birds and water fowl infected by bird flu to help identify the map of the virus allocation.

Hien said the H5N1 virus tested this year showed it has changed slightly from the type that struck in 2004, its virulence was less but the speed of its spread was higher, reported the state-run Nguoi Lao Dong newspaper.

Some samples had been sent for further testing in the United States and the final results to confirm the difference would be available later this month, Hien said.

The Agriculture Ministry said poultry outbreaks have now been reported only in the southern province of Tra Vinh in the Mekong Delta where the virus broke anew last December and spread to 35 of Vietnam’s 64 provinces.

Doctor Hoang Thuy Long, former head of the institute, told a government meeting Wednesday that most of the infected people in Vietnam, including several family clusters, had contact with sick birds.

“Even though so far the transmission mechanism of the disease remains unclear, the avian influenza H5N1 type in Vietnam shows no sign of being spread directly between human and human,” Long was quoted by state-run Quan Doi Nhan Dan daily as saying.