Mad cow disease now in many countries.
Independent researchers carrying out a two-year study for the European Commission say Germany, Italy and Spain are all 'likely to be infected' despite being officially BSE-free.
Infection was 'unlikely but cannot be excluded' in six more European countries, as well as Canada, Australia and the United States.
The experts collected data on each country's import of cattle and meat and bone meal (MBM) from Britain and other BSE-infected countries. They then calculated how well the importing country would have controlled any infection, New Scientist magazine reported.
To restrict BSE, cattle feed should be pressure-cooked and contain no MBM.
A draft of the findings have been posted on the Internet to attract comments from researchers and other government experts.
Germany imported 13,000 British cattle at the height of the BSE epidemic in Britain, plus 1,200 tonnes of British MBM.
The figures for Spain and Italy were similar. Some of this meat, including infection-bearing nervous tissue, was fed to local cattle with insufficient pressure cooking, said the scientists.
These cows could have infected others. In all three countries any BSE infectivity would have been 'quickly amplified'.
Although the EC banned cattle fodder made from cow remains in 1994, infection would have continued to circulate due to contamination of feed mills and inadequate pressure cooking.
All three countries had refused Commission requests to remove high-risk tissue such as brains and spinal cords from cattle carcasses.
'We consider their BSE risk similar to countries with a low, admitted incidence of BSE, such as France,' said one of the experts, Marcus Doherr of the Swiss Federal Veterinary Office.
A similar problem was thought to exist in the US, which imported 126 cattle and 44 tonnes of MBM from Britain.
Germany, Italy and Spain operate a system of 'passive' surveillance which relies on farmers reporting sick animals. But this may completely miss small numbers of BSE cases, it is claimed.
There have been a total of 70 confirmed cases of variant CJD in the UK up to June 2, according to the latest Department of Health figures.