PHNOM PENH, Cambodia — A 6-year-old girl has become the ninth person to die of bird flu in Cambodia this year, as the virus continues to pose a threat to the country, the health ministry said Tuesday.

It said there have been 13 confirmed cases of the H5N1 bird flu virus among humans in Cambodia this year, and 34 since 2005. Bird flu has killed 376 people worldwide since surfacing in 2003, according to the World Health Organization. This year, there have been 20 cases worldwide through June 4, 15 of them fatal, WHO said.

The ministry said the girl came from a village in southern Kampot province, where she was likely to have been exposed to infected poultry. She was treated but died last Friday. The H5N1 virus normally spreads among poultry, but can sometimes spread from poultry to humans.

Of Cambodia's 34 confirmed cases, 23 were children under 14, and 21 of the 34 were female, the ministry said.

"Avian influenza H5N1 remains a serious threat to the health of all Cambodians," Health Minister Mam Bunheng said in a statement. "Children also seem to be most vulnerable and are at high risk because they like to play where poultry are found."