Since the link between BSE and CJD was confirmed, strict controls have been in place to stop BSE entering into the human food chain. These controls include:

• A ban on feeding farm animals on meat and bone meal,
• the removal and destruction of all parts of an animal's carcass that could be infected with BSE,
• a ban on mechanically recovered meat, and
• testing on all cattle that are over 30 months old (experience has shown that infection in cattle under 30 months of age is rare, and even cattle that are infected have not yet developed dangerous levels of infection).

Blood transfusions

There have been cases of variant CJD associated with blood transfusions. In each of the cases, the person received a blood transfusion from a donor who later developed variant CJD. These people then went on to develop variant CJD themselves.

It is not certain whether the blood transfusion was the cause of the infection, as the people could have contracted variant CJD through dietary sources. Nevertheless, steps were taken to minimize the risk of the blood supply for transfusion becoming contaminated. These steps include:

• Not allowing people potentially at risk from CJD to donate blood, tissue, or organs,
• not accepting donations from people who have themselves received a blood transfusion since 1980,
• removing white blood cells - which may carry the greatest risk of transmitting CJD - from all blood used for transfusions.