A Chinese woman has become the world’s first person to die from the H3N8 strain of bird flu, the World Health Organization reported. No human-to-human transmission appears to have occurred, and the risk of the virus spreading is considered to be “low”, officials said.

The 56-year-old woman from China’s southern Guangdong province is the third person known to have been infected with H3N8 since the strain was first identified in North American waterbirds in 2002.

All three cases have been in China, where sporadic human infections with bird flu from exposure to infected poultry are common due to the country’s vast industrial and wild bird populations.

The first two non-fatal cases, both of which likely occurred from direct exposure to infected birds, were reported in April and May last year, the WHO said.

The deceased patient had pre-existing health conditions and had been in contact with live poultry and wild birds around her home. No one in close contact with her has shown any signs of illness.

Preliminary epidemiological investigations into the woman’s death by local health officials suggest that exposure to live poultry at a wet market is the likeliest source of the infection. Samples taken from the market she had visited before falling ill tested positive for influenza A(H3), according to environmental samples collected from the patient’s residence and the market.

“So far, no additional cases linked with this case, nor the previous cases, have been reported,” the WHO said. “The available epidemiological and virological information suggests that H3N8 avian influenza viruses do not have the capacity for sustained transmission among humans.”

Despite the lack of imminent risk, the UN health agency stressed the importance of “global surveillance to detect virological, epidemiological, and clinical changes associated with circulating influenza viruses.”

In February, the death of an 11-year-old girl in Cambodia from the H5N1 strain of avian influenza sparked worries that the virus had evolved to be able to spread in humans. Cambodian health officials have since confirmed no human-to-human transmission occurred.

“The threat is still very low for human-to-human transmission,” Cambodian National Influenza Center director Erik Karlsson said of the conclusions of the investigation into the case by local health authorities. “In terms of mutating into a transmissible virus, that’s quite a distant issue.”

All avian flu cases are detected and reported through the global severe acute respiratory infections surveillance system, which helps the world coordinate and keep track of new respiratory infections.

Image Credits: Roee Sherpnik .