PHNOM PENH, Cambodia (AP) -- A top World Health Organization official, reacting to the death of an 11-year-old girl in Cambodia infected by bird flu, said Friday the recent global spread of the virus and human infections are "worrying."
Dr. Sylvie Briand, the WHO's director for epidemic and pandemic preparedness and prevention, said the U.N. agency is "in close communication with the Cambodian authorities to understand more about the outbreak."
Speaking ahead of a meeting in Geneva on influenza vaccines, Briand called the global situation concerning the virus "worrying given the wide spread of the virus in birds around the world, and the increasing reports of cases in mammals, including humans."
"WHO takes the risk from this virus seriously and urges heightened vigilance from all countries," she said.
Independent experts also have expressed concern over a wave of bird flu that has spread through much of the world since late 2021, posing a potential public health risk.
The Cambodian girl, from a village in the southeastern province of Prey Veng, died Wednesday at a hospital in the capital, Phnom Penh, shortly after tests confirmed she had Type A H5N1 bird flu, according to Cambodia's Health Ministry. She had fallen ill on Feb. 16, and when her condition declined she was sent to the hospital with a fever as high as 39 degrees Celsius (102 degrees Fahrenheit) with coughing and throat pain.
The girl's father tested positive for the virus but has not displayed any major symptoms, health authorities said Friday.
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.
Health Ministry spokesperson Ly Sovann told The Associated Press that the Cambodian father's case is under investigation, and it was not yet known how he became infected. He has been put in isolation at a local district hospital for monitoring and treatment.
A ministry team collected samples from 12 people from the dead girl's village known to have had direct contact with her, and laboratory tests confirmed Friday that only her father was infected.
Health professionals have expressed concern about a wave of bird flu that has spread worldwide in the past year and a half, but consider the current risk to humans to be low.
"There has been a massive global challenge of wild and domestic birds with the current H5N1 avian influenza virus over the last few months and years, which will have exposed many humans; despite this, what is remarkable is how few people have been infected," professor James Wood, head of the veterinary medicine department at England's University of Cambridge, said in an emailed statement.
"Tragic though this case in Cambodia is, we expect there to be some cases of clinical disease with such a widespread infection. Clearly the virus needs careful monitoring and surveillance to check that it has not mutated or recombined, but the limited numbers of cases of human disease have not increased markedly and this one case in itself does not signal the global situation has suddenly changed," Wood added.
According to the World Health Organization, there were 56 bird flu cases in humans in Cambodia from 2003 until 2014, and 37 of them were fatal. Globally, about 870 human infections and 457 deaths have been reported to the WHO in 21 countries, for an overall case fatality rate of 53%. But the pace has slowed, and there have been about 170 infections and 50 deaths in the last seven years. In the vast majority of cases, the infected people got it directly from infected birds.
"Between 2005 and 2020, 246 million poultry died or were culled because of avian influenza," says the World Organization for Animal Health.
"Since October 2021, an unprecedented number of outbreaks has been reported in several regions of the world, reaching new geographical areas and causing devastating impacts on animal health and welfare," the Paris-based agency says on its website.
The U.S. Centers for Disease Control and Prevention agrees that the current H5N1 outbreak is mostly an animal health issue.
"However, people should avoid direct and close contact with sick or dead wild birds, poultry, and wild animals," it warns on its website. "People should not consume uncooked or undercooked poultry or poultry products, including raw eggs. Consuming properly cooked poultry, poultry products, and eggs is safe."