'Hepatitis C detector' sells hope and nothing more

http://www.guardian.co.uk/science/blog/2013/feb/28/hepatitis-c-detector-sells-hope


Dr Gamal Shiha demonstrates the prototype of a device that he claims can remotely detect the hepatitis C virus. Photograph: Patrick Kingsley/Guardian

A new device that supposedly detects diseases remotely is being promoted. According to an excited report earlier this week in the Guardian, about a demonstration of the device in an Egyptian hospital, its developers hope it will first be used to detect swine flu and hepatitis C, and later other diseases.

What is being plugged here is hope and nothing more. The device looks like a car radio aerial attached to a handle. It is said to work by detecting a specific frequency emitted by infected liver cells. It is claimed it can detect the disease in a patient from across a room, has never failed to pick up the disease in any patient who has it, and wrongly detects hepatitis where there is none (a "false positive&quot only 2% of the time.

This degree of reliability is a miracle if you consider that most commonly used blood test for hepatitis C give a false positive result around 15% of the time. No blinded tests have been published, which is surprising given how implausible it is that this new device should work at all, never mind achieve these kinds of detection rates.

I cannot think of any scientific mechanism through which an aerial on a handle could pick up electromagnetic frequencies from cells inside the body, because even the most sensitive scanners cannot do this.