Doctors have discovered Britain's third suspected case of transmission of the human form of mad cow disease through blood transfusion, the Health Protection Agency said on Thursday, according to Reuters. The case of variant Creutzfeldt-Jakob Disease (vCJD) was diagnosed in a patient who had received a transfusion eight years ago. The donor had developed symptoms of the fatal disease 20 months after giving the blood. Variant CJD is the human equivalent of Bovine Spongiform Encephalopathy (BSE) or mad cow disease, linked to eating meat infected with BSE. The illnesses are caused by brain proteins that transform themselves into infectious agents. Britain has recorded 160 cases of vCJD, of whom 154 have since died. The agency said the case was further evidence that vCJD can also be transmitted by blood transfusion. The first two cases linked to donated blood were reported in 2004. --More 23 00 Local Time 20 00 GMT