A deadly strain of avian influenza has broken out in China and Thailand, but officials are claiming the outbreaks are under control.

The H5N1 strain of bird flu spread across parts of Asia earlier this year, decimating poultry stocks, causing millions of poultry to be culled, and killing 24 people in Thailand and Vietnam.

Thailand confirmed it had detected new outbreaks of the H5N1 strain at two farms near towns north of Bangkok, while China confirmed the presence of the virus at a farm in the central province of Anhui, reported Reuters.

In Thailand the cause of the outbreak is being investigated, but in China it has been blamed on migratory birds.

Earlier this year bird flu outbreaks resulted in the deaths of more than 40 million chickens in Thailand, which was one of the world's largest poultry exporters.