Bird flu has been confirmed in a fourth Vietnamese province after tests on 70 ducks showed they had died from H5N1 avian flu virus, a government report said on Wednesday.

The results of tests on ducks found dead at the weekend prompted health workers to slaughter around 1,800 more ducks in two communes of Kien Giang province in the southern Mekong Delta, the Animal Health Department report said.

State-run Voice of Vietnam radio said checkpoints had been set up in the two communes to prevent farmers from moving birds out for sale.

Vietnam has had no human H5N1 cases since November 2005 but the virus that first struck the delta region in late 2003 re-emerged last month.

On Tuesday Vietnam received $18.7 million from donors for projects to boost training and disease surveillance and to help with a poultry vaccination campaign.

According to the World Health Organization (WHO), bird flu has killed 42 of the 93 people infected in Vietnam. In total, it has claimed 157 lives since 2003 and has spread from Asia to Europe, the Middle East and Africa.

On Wednesday, China reported its first human case of the deadly virus since July last year.

Experts fear the virus could mutate into a form that is easily transmissible among humans and might spark an influenza pandemic that would kill millions.