TORONTO After polling some 2,200 Canadians, a government-commissioned advisory group recommended Monday that Ottawa not allow human trials on transplanting live animal organs into humans until more is known about the risks.

Many doctors are excited by the idea of so-called xenotransplants due to a worldwide shortage of human transplant organs.

But many governmental health bodies are cautious amid evidence that killer viruses, from HIV to lassa fever and ebola, are able to leap the species barrier to humans.

The Canadian group's recommendations to Health Minister Allan Rock follow last week's announcement by two scientific teams -- one in Britain and another in the United States -- that they had cloned a batch of pigs which lack a gene that cause pig organs to be rejected by the human body.

The non-profit Canadian Public Health Association, commissioned by Health Canada last year, conducted citizen forums in six Canadian cities and also carried out mail, phone and Internet interviews.

The advisory group found that initially Canadians supported proceeding with xenotransplantation in human trials, but when better informed of its risks changed their minds.

For example, of the 107 people interviewed in the forums, initially 55 percent had been in favor of xenotransplantation, 27 against and 18 percent undecided. At the end of the two-day forums, 46 percent supported proceeding with the transplants, 53 percent were against and one undecided.

"Canadians recognize the critical shortage (of organs) ... however, at this time, they still felt that the risks outweighed the benefits," doctor Heather Ross, a co-chair of the group, told AFP.