Authorities in Germany have identified a marten infected by the lethal H5N1 bird flu virus, the second species to be found with the disease. The discovery of the virus in the weasel-like creature comes days after three domestic cats were found to have the highly pathogenic strain on Germany’s Baltic island of Ruegen. However, experts stress that the nature of the threat has not changed.Serbia meanwhile has confirmed its first case of the deadly strain in a swan found last week in the northern Sombor region, close to the Croatian border. Authorities are now increasing measures to contain the spread and have widened the radius of the risk zone where the bird was found dead. Belgium however is breathing a sigh of relief after a man suspected of having contracted the lethal virus tested negative. He was admitted to hospital in Brussels on Monday with worrying symptoms, following a visit to China.