Hong Kong yesterday imposed restrictions on the importation of Japanese beef, one day after Tokyo announced the first suspected case of mad-cow disease in Asia. The move fell short of immediate bans on beef imports from Japan imposed by Singapore and South Korea. SAR importers now have to obtain prior approval from the Food and Environmental Hygiene Department before importing beef from Japan. They also are required to submit health certificates issued by Japanese authorities stating that meat-and-bone meal is not used to feed cows, that all cows have passed inspection by veterinary officers, and brain and spinal cord are not part of the consignment. The meat will also be held on arrival in the SAR to allow food inspectors to check the health certificates. The control measures were taken after the department contacted the Japanese Consulate-General to inquire about Monday's announcement that mad-cow disease had been discovered in a five-year-old Holstein cow at a farm in Chiba prefecture, west of Tokyo. It said no beef had been imported from Chiba in the past three years and that Japanese beef accounted for a very small portion of total imports. Mad-cow disease, also known as BSE - bovine spongiform encephalopathy - is a brain-wasting illness that has been linked to the human variant Creutzfeldt-Jakob disease (CJD), which has killed about 100 people in Britain since the mid-1980s. A Hong Kong woman who contracted CJD in Britain was yesterday still in a stable condition at Prince of Wales Hospital. Legislator Dr Lo Wing-lok, who represents the medical sector, said the SAR Government had made 'a considered response' rather than a 'knee-jerk reaction'. He said food import controls were more effective than bans. One Hong Kong microbiologist said he did not believe Asia would witness a serious spread of mad-cow disease or its human variant because cattle in the region were fed mostly grass, instead of a bone-meal diet. 'What we have to be concerned about is the recycling of nerve tissue - brain and spinal cord - in food products, such as sausages and hamburgers,' he said. Until Japan's announcement on Monday, mad-cow disease has only been confirmed in Western Europe. The World Health Organisation said the discovery in Japan has yet to be confirmed by tests in Britain but its detection was not 'totally unexpected'. Last year, Hong Kong imported 55 tonnes of beef from Japan, accounting for about 0.1 per cent of the total. Between January and May this year, 31 tonnes were imported from Japan. Hong Kong relies on the mainland for most of its food and the department said beef from there was BSE-free.