There actually is a fully reliable test for Lyme Disease - a DNA PCR test. It is available via the NHS from the UK Lyme reference laboratory in Southampton. GPs are almost certain never to have heard of it but insist on them contacting the local Infectious Diseases Unit who certainly should be well aware of the availability of the test and should easily be able to find it if not. A positive result is unequivocal and a negative means almost certainly negative (I can't recall the false negative rate but it's pretty insignificant). Note that just because a positive result is obtained, the thinking is that you may have actually cleared the infection, though almost certainly only with with antibiotic use - Doxycycline is the main one (100mg X2 a day for two weeks). Which, luckily, tends not to upset the gut so badly since it's absorbed very rapidly and doesn't make it to the large intestine. However a positive result means you either had it recently (months) or have it now. How do I know all this? I've had Lyme and it gave me quite a kicking. I'm still recovering from aspects after two years - but whatever doesn't kill you makes you stronger! ;) David Wood ( http://drw.me.uk/RedYeti/ )