Indonesia prepared more hospitals to deal with bird flu cases and Japan confirmed a first outbreak of H5N1 in poultry in three years on Tuesday as the virus flared again in Asia, mirroring past winters.
Concern about the disease have rippled across the region, with an Indonesian hospital struggling to cope with suspected human cases this week, and the virus spreading among flocks in Vietnam and flaring again in Thailand.
The World Health Organisation (WHO) said there were no signs of the virus spreading between humans and the response of most affected countries was much better than in the past. "Obviously we are very concerned if this virus should develop the ability to transmit between humans. We have not seen any clear sign of that yet. We are hoping it will stay the way it is," Peter Cordingley, WHO spokesman for the Asia-Pacific, told Reuters Television in Manila.
The WHO says bird flu has infected 267 people in 10 countries and killed 161 since 2003. There are fears that millions could die if the virus were to mutate into a form that passes easily from person to person. Four Indonesians have died already this year, taking the number killed by bird flu in the country to 61, the highest in the world.
In Geneva, the WHO's top bird flu expert said an unknown number of Muslims returning from the annual Haj pilgrimage in Saudi Arabia were treated in hospital in Indonesia for fever, a common symptom that could signal bird flu.
Indonesia has struggled to contain the disease as millions of backyard chickens live in close proximity to humans and health education campaigns have often been patchy.
A doctor at Jakarta's Persahabatan hospital, one of two designated to treat bird flu cases in the capital, said it was overwhelmed with patients with bird flu symptoms.
H5N1 has spread across much of Asia, into Europe, the Middle East and Africa. Migrating birds and poultry smuggling are believed to be some of the ways the lethal virus has spread.