List of enterovirus infection studies

In this list of studies looking for evidence of enterovirus infection in ME/CFS patients ➕ indicates a positive study (one finding enterovirus much more commonly in ME/CFS patients than healthy controls) and ➖ indicates a negative study (no difference between patients and healthy controls).

Early ME/CFS enterovirus research
This early period of enterovirus research from 1970 to 2003 (comprises mainly British studies).

Dr John Chia's ME/CFS enterovirus research
John Chia in California: his research papers on enterovirus in ME/CFS from 2005 to present.

Other investigations by John Chia
Dr Chia took more than 2500 blood samples from more than 510 ME/CFS patients, and in their peripheral blood lymphocyte (PBL) cells, 35% of these patients tested positive for enterovirus RNA, using a very sensitive test: the Chemicon RT-PCR EAI 3 primer test, with Qiagen 1-step RT-PCR enzyme.

Interestingly, for the more severe bedridden patients, Dr Chia found enterovirus RNA in 70% of the PBL cells. But for the less ill patients, enterovirus RNA was found in only 12%.

The sensitivity of the test was high, around 80 to 800 RNA copies per ml of blood, yet typically the same patient would not always test positive using this test (they would be positive on some occasions and negative on others), so Chia says it is clear that the enteroviral RNA present in the blood in ME/CFS is at very low levels. Dr Chia says any PCR tests which have a lower sensitivity, one above 1000 copies of RNA per ml of blood, will almost always give negative results in ME/CFS patients.