HANOI, 7 February 2004 — The human toll in Asia’s bird flu crisis rose yesterday to 18 with two more deaths in Vietnam, and a UN official said preliminary tests indicated pigs might have the virus that has infected tens of millions of chickens across the region.

China investigated mysterious reports of finches dropping dead from the sky and villagers in Indonesia set thousands of birds ablaze as they tried to rid the resort island of Bali of the deadly disease.

Ten countries are battling bird flu, culling 50 million chickens and other fowl as international health officials seek ways to contain a virus that has rapidly spread across half of the Asian continent.

Bird flu has jumped to people in Vietnam, where 13 have died, and Thailand, where the toll stands at five, with health officials tracing most of those cases directly to contact with sick birds.

But experts have said it’s possible the virus jumped to people through another mammal, such as pigs, which have been implicated in human flu epidemics in the past. Anton Rychener, representative for the UN Food and Agriculture Organization in Hanoi, said “nasal swabs taken from pigs have been positive for H5N1,” the deadly strain of bird flu. “It continues to be under investigation and is of concern.”

However, an expert at the agency’s headquarters in Rome said no such data was found. The reason for the discrepancy between the two FAO experts was unclear. Other health officials expressed caution about reading too much into the early results.

Doctors in Vietnam on yesterday announced two additional deaths, a 6-year-old girl from southern Dong Nai province and a 24-year-old man from central Lam Dong province.

Experts at an emergency meeting overnight in Rome endorsed a strategy of vaccinating healthy chickens alongside the continuing slaughters of infected poultry that the WHO has said is the best way to deal with the outbreak.A widely available human vaccine is believed about six months away, but some bird vaccines are available now.

Indonesian villagers held an unusual cremation ceremony, meanwhile, aimed at ridding Bali island of bird flu, sprinkling thousands of sick chickens with water and then setting them ablaze.

Officials in eastern China were looking into a mass death of brambling finches, a migratory sparrow-like bird that winters throughout China.

One official in the Jiangsu province city of Taizhou said about 100 brambling finches fell dead from the sky in the city’s Kou’an town. Blood samples were taken the same day but results were not yet available, she said.

Other accounts put the number of dead birds much higher, with one official saying about 6,000.

The head of the Kou’an town government, who gave his surname as Gao, said he doubted that number or that the birds died from flu.

“Since when do you see that many birds together all at once?” Gao said. “Maybe they all ate some poisonous food. Let’s wait and see the results of the tests.”

WHO has said the virus is believed to spread across regions via migratory birds, but exactly how it spreads is not well understood.