An airline has been ordered to disinfect a plane that carried a four-year-old boy infected with the deadly E. coli bacteria to Hong Kong. Health department director, Dr Margaret Chan Fung Fu-chun, said the department had assessed the risk to passengers on the plane. 'We've asked the airline to have extra disinfection on top of its routine cleansing procedure,' she said. The chance of catching the disease from the plane's toilet was slim, she said, and there was no need to name the flight number or alert fellow passengers. The boy, infected with the E. coli O-157:H7 bacteria during a holiday in Britain, remained stable last night after a week in Adventist Hospital. He was admitted suffering from diarrhoea after drinking unpasteurised milk on a farm. The health department is checking whether farms in the New Territories are selling unpasteurised milk for consumption. The boy, who is British, is the first victim of the O-157:H7 strain of bacteria confirmed in Hong Kong.