Public health authorities in Romania are awaiting results from analysis of new suspected bird flu cases. The agriculture ministry in Bucharest said earlier tests on three ducks owned by a local family showed positive. The zone, in the Danube Delta region, has been put under quarantine and suspect birds are being culled. The samples have been sent to a laboratory in the UK for further analysis.The wetlands of the Delta are an important area for birds migrating from Russia and northern Europe. This week’s meeting of top medical experts on the threat has prompted the US government to take urgent steps against a possible pandemic. Although the virus is affecting birds now, there is concern it could mutate into the H5N1 strain which can be lethal to humans. Washington is urging countries concerned to step up public health controls.