ITV News Health Correspondent Martin Stew explains the situation with bird flu and if it is dangerous to humans
The death comes amid heightened concerns over a wave of bird flu that has spread through much of the world since late 2021, posing a potential public health risk.
Millions of birds have died and the disease is now on almost every continent on Earth.
The girl, from a village in the southeastern province of Prey Veng, died on Wednesday at a hospital in the capital, Phnom Penh.
Bird flu, also known as avian influenza, normally spreads between sick poultry but can sometimes spread from poultry to humans.
The recent detection of infections in a variety of mammals, including at a large mink farm in Spain, has raised concern among experts that the virus could evolve to spread more easily between people, and potentially trigger a pandemic.
Cambodia said it is investigating the father's case but it is not believed he caught it from his daughter. He has been put in isolation at a local district hospital for monitoring and treatment.
"There is always a risk of human infection, particularly in people in close contact with poultry or wild birds, and this risk increases during times where circulation of avian influenza is particularly high, as it is now," Jonathan Ball, professor of molecular virology at the University of Nottingham said.
The risk to humans remains low with vaccines already developed should the virus mutate and person-to-person transmission starts being reported.
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