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Commentary
Vaccine Pandemic Conerns
Recombinomics Commentary
04:05
August 4, 2011
DR. GELLIN: I am always impressed by
what a body of work that is. Two questions. One of them, you had
mentioned about the low reactors and the biological issues at the lab
in London, is that the same issue for the H1 as well as the H3? Because
they showed, I think, that there was a higher percentage of H1 low
reactors in the London lab, as well. The question really is that a lab
problem or does that signal some other evolution, since they have had
more H1 this year?
DR. COX: Yes. What we know
for H1N1 viruses is that if you isolate them in a particular cell line,
you tend to get more of the variance with changes within that region
that I mentioned -- the 153 to 158 region. They had been using the
particular cell line that pulls out that particular variant or that
selects for that particular variant.
They have subsequently
switched to normal MDCK cells. I think what they are seeing is a
combination of the two phenomena. Plus, they receive a lot of viruses
that have been isolated COT, the special kind of MDCK cells. I think it
is a combination of they are receiving viruses with changes that cause
that reduction in activity and then having some additional low
reactors, but they are scattered throughout the tree.
The above quotes are from the US FDA's
Vaccine Advisory meeting in February.
CDC was complaining about the high level of LOW
REACTORS being reported by other centers (Mill Hill), which the CDC
attributed to lab error (use of cell lines that select for low
reactors) creating "spontaneous mutations" leading to isolates
"scattered throughout the tree". However, these "lab errors" are
precisely the changes that identify low reactors, as well as those that
target the lung, causing more severe and fatal disease. This is why the
CDC discounted the importance of D225G and D225N, which have been
linked to severe and fatal cases. At the February meeting the old
vaccine targets were unanimously recommended (with one abstention
on H1N1), in spite of record high
pneumonia and influenza death rates.
That meeting was followed by testing using eggs, including samples
where H1N1 was previously isolated on "normal" MDCK cells. The new
isolates (on eggs) had a high
frequency of Q226R and now the CDC is testing new vaccine targets
for pandemic H1N1 (which have K157E and Q226R), seasonal H3N2,
influenza B, as well as pandemic H3N2 (trH3N2). Pandemic H3N2 has D225G
and would likely be selected in egg isolates, which may have markedly
increased the number of detected (but unreported) trH3N2 isolates.
This sequence of events raises concerns that low reactors, including
H1N1 with Q226R, are widespread and associated with severe and fatal
cases. The vaccine made with the new
target with K157E and Q226R was tested against the old vaccine and
the testing was characterized as TWO WAY LOW FAIL, signaling vaccine
failure (the old vaccine poorly recognized the new target, and the new
vaccine poorly recognized.the old target).
Vaccine targets are usually selected in February at the selection
meeting pruduction of a new vaccine which is distibuted in September
for teh flu season in the northern hemisphere. The release of the
sequences in August strongly suggests that these new targets were not
used for the vaccine under production for September shippingt.
Information on shipments dates of new vaccines and the reasons behind
the selection of the new targets, including pandemic
H3N2 (trH3N2), are past due, like production of an effective
influenza vaccine.
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