The revelation that in the absence of circulating chickenpox virus,
adults who had experienced chickenpox as children are at an increased
risk of shingles, was reported in a recent Scandals.
Clearly, the prospect for an increased risk of adult shingles
as a result of vaccination is worrisome, as is using vaccination to
solve a problem vaccination itself has caused.
As disturbing as this particular result is, however, is it
legitimate to assume that this result, while unfortunate, is just an
isolated outcome and of no relevance to other vaccines and the diseases
they are designed to prevent? Or are there implications for
vaccination policy beyond the specific relationship between chickenpox
vaccine and the potential for shingles in adults?
Unfortunately, this does not appear to be an isolated outcome.
In a 1999 study entitled "Reduced passive measles immunity in
infants of mothers who have not been exposed to measles outbreaks"
and published in the
Scandinavian Journal of Infectious Diseases, it was reported that
"Geometric
mean titres (GMTs) of cord blood NT (measles) antibodies gradually
decreased after 1989 and the GMTs of the most recently born infants
were significantly lower than those of infants born in the first few
years of the study.
These observations suggest that even in mothers who experienced natural
measles in childhood, recurrent exposure to natural measles is
necessary in order to maintain adequate antibody levels for effective
passive immunity of their infants".
While the conclusion
drawn by the authors of this study was that naturally measles-immune
mothers, in the absence of periodic exposure to measles, do
not appear to pass on immunity to their infants, the implication
of this study is that measles vaccination, to whatever extent it
prevents circulation of measles virus, may prevent those who are
naturally immune to measles from maintaining their immunity.
It has long been assumed that measles immunity is lifelong.
According to Krugman
et al, in his citation of the
Panum
report of a 1846 epidemic of measles in the Faroe Islands, it was
allegedly demonstrated "that repeated exposure to the disease was not a
necessary prerequisite for permanent immunity to measles". The
1999 study cited above, however, would seem to refute this widely
accepted conclusion.
Thus it would appear that those who have naturally experienced two
diseases at least, i.e., chickenpox and measles, require repeated
exposure in order to avoid immunity loss.
Do
these unexpected results, in fact, indicate that natural immunity is
not automatically lifelong? Can natural immunity actually wane under
certain circumstances?
If
so, what are those circumstances?
Does
vaccination interfere with lifelong immunity? If so, is the loss
of this very important and effective aspect of immunity an acceptable
risk of vaccination?
Where
is the follow-up of this important study?
Are
once naturally immune children, because of vaccination, now going to be
at risk for so-called "vaccine preventable" diseases as adults?
If
so, what does this say about "expert" understanding of the immune
system?
And what does
this study, and its implications, say about the wisdom of vaccination
in general?
Is it really prudent to tinker with such a complex and critical
biological process, particularly in the absence of disease (as is the
case with vaccines given to healthy infants, children and adults)?
Sandy
Mintz