Authorities in the north German state of Schleswig-Holstein on Tuesday ordered that all poultry be kept indoors following the discovery of bird flu in two farms in the region.

Type H5N8 bird flu was confirmed in a second poultry farm in Schleswig-Holstein on Monday following a case on another farm in the state last week.

A series of outbreaks of the highly pathogenic bird flu have been reported in Europe in past weeks and Dutch health officials on Tuesday ordered the culling of 48,000 chickens following a separate outbreak on a farm.

Wild birds are believed to be spreading the disease.

Schleswig-Holstein’s order to keep poultry indoors would be hard for some farmers but is needed to prevent more farm birds catching the disease, the Schleswig-Holstein state agriculture ministry said in a statement.

The disease is spreading rapidly among wild birds in the state, the ministry warned, and authorities are currently examining the deaths of over 3,000 wild birds there.

Britain ordered a cull of 13,000 birds at a farm in northwest England after detecting cases there while South Korea’s agriculture ministry said on Tuesday it had confirmed the H5N8 strain of bird flu in samples from wild birds in the central west of the country.

Risk to humans from the disease is considered low, but past outbreaks among farm birds have needed extensive slaughtering programmes to contain it.