People carrying variant Creutzfeldt-Jakob disease (CJD) could be identified from a urine test, research suggests.
An international team - including researchers at the University of Edinburgh - say the test could become a useful tool for easier diagnosis of people with the condition. It could also help to screen for people who are carrying the disease but who do not show any symptoms.
Variant CJD - which is linked to bovine spongiform encephalophathy (BSE) in cattle - is caused by infectious proteins called prions.
The researchers discovered that patients with variant CJD had traces of prions in their urine using a new, high powered technique.
This is the first time that we have been able to detect prions in the urine of patients with variant CJD. It opens the door to the development of a screening tool for people infected with CJD who do not show any symptoms, which is of particular concern in the UK for securing the safety of our blood supply.
The technique, developed by scientists at The University of Texas Medical School at Houston, is highly sensitive and can detect even very small quantities of prions.
The findings are published today in the New England Journal of Medicine.
This could lead to the development of commercial technology for diagnosis as well as to determine the safety of donated blood and urinary products.
Variant CJD can be transmitted by eating beef that is infected with BSE or by receiving a blood transfusion from a person who carries the infectious prions. It can take a long time after infection before symptoms appear and people can unknowingly carry the disease for many years.
The disease remains very rare - 229 people have died from variant CJD since it was first identified almost 20 years ago, of which 177 were from the UK. However, it has been estimated that as many as one in 2000 people in the UK could be carrying infectious prions without showing any symptoms.