The European Union is urging countries to ensure that domestic animals do not come into contact with wild birds, as concerns grow over the spread of avian flu. In Sweden, the virus has been found in two dead wild ducks, and tests will reveal if it was the the deadly H5N1 strain that is known to have infected a cat in Germany.After the domestic cat was found dead on the virus-hit Baltic island of Ruegen, Germany told people to keep their cats indoors and their dogs on a leash in areas hit by bird flu. France was the first EU country to report bird flu on a farm. Now Paris is asking the 43 countries that imposed restrictions or bans on French poultry imports to limit the measures to animals from the eastern region hit by the outbreak. The World Health Organisation, meanwhile, says unlike in birds, there is no evidence that domestic cats provide a reservoir for H5N1. WHO expert Jean-Francois Saluzzo says: “If the virus changes into a form that can be passed from human to human, it won’t happen in Europe.” Experts fear weak detection systems in Africa combined with limited awareness about avian flu could help its spread.