Egypt, hit hard by bird flu, has ordered the slaughter of every pig herd in the country as a precaution against swine flu, a step the United Nations said was a mistake, Reuters reported. The H1N1 swine flu virus is spread by people and is not present in Egyptian animals but culling pigs, largely viewed as unclean in Muslim Egypt, could help quell any panic. Twenty six people have died in Egypt from the highly pathogenic H5N1 bird flu virus and experts fear any flu pandemic could have a devastating impact in a country where most of the roughly 80 million people live in the densely packed Nile Valley, many in crowded slums in and around Cairo. But the United Nations said the mass cull of up to 400,000 pigs was "a real mistake". "There is no reason to do that. It's not a swine influenza, it's a human influenza," said Joseph Domenech, the U.N. Food and Agriculture Organisation's chief veterinary officer, told Reuters. He said the FAO had been trying unsuccessfully to reach Egyptian officials. Pigs are mainly raised by Egypt's Christian minority. In a statement earlier on Wednesday, Health Minister Hatem el-Gabali said: "It is decided to slaughter all swine herds present in Egypt, starting from today." Cabinet spokesman Magdy Rady said Egypt would compensate farmers for their losses. Rady said swine farms in Egypt were in poor condition and constituted a health hazard. "That's why people are really getting afraid," he told Reuters before the decision was taken. Swine flu has killed up to 159 people in Mexico and one in the United States, and cases have also been reported in Europe as well as in neighbouring Israel. Egypt has not reported any cases, but has stepped up monitoring at airports. Egypt has been harder hit by the H5N1 bird flu virus than any other country outside Asia.