"It is almost unheard of to find an association of this magnitude in any
study of an infectious agent and a well-defined disease, much less an
[ill-defined] illness like chronic fatigue syndrome," he said in an e-mail.
It is extremely difficult to prove causation with a ubiquitous virus like
XMRV, and it "is even more difficult in the case of CFS, which represents a
clinically and epidemiologically complex illness," he said.
This quote is similar to the last quote so the same points apply except that
he is now saying that XMRV is a "ubiquitous virus".
Some viruses could be said to be "ubiquitous" e.g. most of the adult
population will have some sort of antibodies to EBV.
However, the XMRV virus was only identified in 8 of 218 (3.7%) healthy
controls (compared to 68 of 101 patients (67%) of the patients).
The researchers also did some extra experiments, summarised in plain English
"Testing the white blood cells from thirty CFS patients showed that 63% (19
people) of the samples tested showed viral proteins. Tests on samples from
five healthy controls did not show any viral proteins.
"Overall, samples from people with CFS were 54 times as likely to contain
viral sequences as samples from healthy controls.
"The researchers found that XMRV found in the white blood cells of CFS
patients could be transmitted to prostate cancer cells when grown together
in the laboratory. In 10 out of 12 people with CFS (83%), fluid taken from
their blood samples could also infect the prostate cancer cells in the
laboratory. Similar results were found when uninfected white blood cells
were exposed to this fluid. Fluid from the blood samples of twelve healthy
controls did not infect the prostate cancer cells.
"The researchers found that half (nine out of 18) of CFS patients carrying
XMRV DNA had antibodies against a similar virus, while none of the seven
healthy controls tested showed an antibody response. This suggested that
half of the CFS patients had had an immune response to the XMRV."
To summarise, these experiments (admittedly using smaller sample sizes)
again don't show XMRV to be ubiquitous like Bill Reeves claims.
Don't support the Reeves/empirical definition/criteria for CFS?
Sign the petition at: http://CFSdefinitionpetition.notlong.com