A 44-year-old woman has died of the H5N1 bird flu virus in the southern Chinese province of Guangdong.

The Guangdong’s Center for Disease Prevention and Control said in statement on its website that the woman, identified by only her surname Zhang, was employed in Haifeng County and tested positive for H5N1.

“This lady kept some chickens in her backyard and they became sick and died during the incubation period of her illness. She also ate some of the chickens herself. The most likely route of transmission was from the sick poultry she kept and she acquired avian influenza from this source,” said Thomas Tsang, controller of Hong Kong’s Center fro Health Protection, quoted by Reuters.

The statements also read that the woman became sick February 16, presenting symptoms of fever, cough, and pneumonia, but she was admitted to the county hospital on February 22, after first seeking treatment at a local clinic. She died on Monday after treatment failed.

China has already reported two other H5N1 deaths this year. Since the virus began ravaging poultry stocks in Asia back in 2003, China has had 19 human bird flu deaths, the World Health Organization said. According to the same organization, Indonesia has the highest number of bird flu deaths in the world, which now stands at 105 out of the 129 cases in the country. More than 225 people have died worldwide from bird flu.

Health experts fear that the virus, which is usually spread through human-bird contact, could mutate into a form easily passed from human to human and millions of people could die because they would have no immunity to the new strain. So far, most human cases have been linked to contact with infected birds.