Dutch authorities have reported a new outbreak of bird flu on a western poultry farm.

“Avian influenza has been detected on a poultry farm at Zoeterwoude, where some 28,000 birds are affected,” the economy ministry said in a statement.

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“The birds are infected with the H5 variant of the flu but it’s not yet known whether of the highly pathogenic variety or not.”

The highly-infectious H5N8 strain of bird flu was discovered in the Netherlands two weeks ago, where authorities suspect it might have been brought in by birds migrating from Asia.

Some strains of avian influenza are fatal for chickens, and pose a health threat to humans, who can fall sick after handling infected poultry.

The H5N1 strain of bird flu has killed more than 400 people, mainly in Southeast Asia, since first appearing in 2003. Another strain of bird flu, H7N9, has claimed more than 170 lives since emerging in 2013.

The latest outbreak lies about 35km northwest of Hekendorp, where the first outbreak was detected in mid-November, leading to around 150,000 birds being destroyed.

Bird flu has been detected in at least three other locations in the Netherlands and Germany, and Britain has also reported similar strains of the virus.

Authorities were destroying the birds at the latest outbreak at Zoeterwoude and have thrown a 10km cordon around the farm.