"The human mortality rate from bird flu in Indonesia is the highest in the world and there will be more human cases if we do not focus more on containing the disease at source in animals," Joseph Domenech, chief veterinary officer of the U.N. Food and Agriculture Organization, said in a release.

Avian influenza has been reported in 31 of Indonesia's 33 provinces. The virus is endemic in Java, Sumatra, Bali and southern Sulawesi, with sporadic outbreaks reported from other areas, the report said.

"The avian influenza situation in Indonesia is grave," Domenech said. "All international partners and national authorities need to step up their efforts for halting the spread of the disease in animals and making the fight against the virus a top priority."