Researchers say they can detect mad cow disease in human blood

Researchers have come up with a way to detect the proteins that cause mad cow disease in a person’s blood, according to a paper published online Wednesday in the journal The Lancet.

Mad cow disease, which humans can get by eating beef from infected cattle, has killed 171 people and been responsible for the deaths of more than 4 million cattle, slaughtered in attempts to eradicate the disease. Officially known as variant Creutzfeldt-Jakob disease, the infection is caused by prion proteins that cause the brain to start breaking down.

The disease can also be passed through blood transfusions – and there’s no test to detect it.

But now, British researchers have come up with a screening test that can detect the abnormal prion protein that’s associated with the infection. They ran the test on 190 samples, and it was able to pick out 15 of the 21 samples from people with the disease. That’s a 71.4% success rate. On top of that, the test didn’t turn up any false positives – in other words, it didn’t incorrectly indicate that the abnormal prion was in any of the healthy samples.

Time to roll out a mad-cow screener? Not so fast, Luisa Gregori of the Food and Drug Administration wrote in a commentary: It’s unclear whether the test is sensitive enough to detect the disease in people who are in the early stages of the disease and haven’t shown any symptoms yet.

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