LONDON -- Scientists say tests on animals suggest there may be a risk of people catching the human form of BSE through blood transfusions, according to reports.

Tests at the Institute of Animal Health indicated that one in six animals given blood from infected sheep appeared to develop the illness, **** The Guardian **** newspaper says.

The study suggests red cells and plasma may have infectivity for VCJD -- the human form of BSE which destroys brain tissues -- but the full version of the research is not published until November.

Scientists previously demonstrated transmission of BSE in animals, but in animals fed infected brain.

The National Blood Service said the research was valuable, but stressed there was no risk of contracting the disease by giving blood.

"We need to collect 10,000 units of blood a day to ensure lifesaving treatments can continue. Therefore it is vital that donors keep giving blood and that new donors keep coming forward," said a spokesman, according to the BBC News On-Line.

The study's authors suggest the risk of VCJD transmission through blood may be "appreciable" where the government had previously described it as "theoretical".