The World Health Organisation has called for people suspected of having caught the lethal strain of bird flu to be placed in immediate isolation, and checked for 14 days.H5N1 has been detected in birds in Croatia, Romania, Turkey and Russia, but Europe has not reported any human cases. French authorities say tests on one of three people suspected of having bird flu on the French Indian Ocean island of Reunion have proved negative for H5N1. Still, health fears have sent poultry sales plummeting. A spokesman for a French poultry producer said: “Sales dropped by 30 per cent in two weeks, due to the consumers’ totally irrational worries, they’ve been frightened for nothing.” The WHO said yesterday that everyone working on farms with bird flu outbreaks or at risk of them should wear protective clothing. Meanwhile China says a girl who died in a village hit by the country’s latest outbreak in fact had pneumonia not bird flu. Still, fears remain that H5N1 will mutate into a form that could pass easily between humans. In the absence of a vaccine many people are turning to antiviral drugs like Tamiflu. Its Swiss producer, Roche, is suspending deliveries to the United States until it actually sees increased incidence of seasonal flu. The firm says it fears consumers will deplete stocks by hoarding the medecine at home.