Police tape and warning signs are seen outside a duck farm in Nafferton, northern England November 17, 2014.
AMSTERDAM (Reuters) - A second Dutch farm was hit by an outbreak of bird flu, the government said on Thursday, prompting the destruction of 43,000 chickens and prolonging restrictions on trade in the world's leading egg-exporting country.
A three-day, nationwide ban on the transportation of all poultry, eggs and related farm products was extended until Sunday, a statement said.
The measures have already caused up to 100 million euros ($125 million) in losses for farmers, said Gert-Jan Oplaat, president of the poultry farmers' association. Industry groups say an extension could bankrupt smaller producers.
Infections have also been discovered on farms in Germany and Britain.
The infection announced on Thursday was of the H5 strain, the government said, but it was unclear if it was the highly-contagious H5N8 virus discovered last week at a farm 20 km (12 miles) away.
As in the previous outbreak, authorities imposed a 10 km (6 miles) exclusion zone around the farm in Ter Are, in the central Netherlands, and were testing four nearby farms for the virus.
The first case in the Netherlands was reported last weekend in the village of Hekendorp, prompting the culling of 150,000 laying hens.
Tests show that bird flu viruses found in Germany, the Netherlands and Britain are similar to one that devastated poultry flocks in South Korea earlier this year, the World Organization for Animal Health (OIE) said on Wednesday
"They are very, very close, which reinforces the theory of a transmission through migrating birds," OIE Director General Bernard Vallat told Reuters, adding that genetic analyses had pegged similarities at 99.8 percent.
The German and the first Dutch outbreak are of the H5N8 strain, which is highly contagious in birds. H5N8 has never been found in humans, unlike H5N1, which has killed 400 people mostly in Asia and the Middle East since 2003 and caused a global scare.
There can be no exports of poultry products as long as the transportation ban is in place and the latest measures could lead to a supply shortage.
About 2,000 Dutch businesses, with more than 100 million chickens, export more than 6 billion eggs a year. The Netherlands is also the EU's leading exporter of poultry meat.
