Vaccines are usually touted as one of the safest, most effective
public health measures of all time. One of the cornerstones of
vaccine policy is that regardless of arguable risk, vaccines are very
effective at preventing disease.
It must be said at the outset that I believe vaccines are effective
to some degree (depending on how "effective" is defined), and do not
count myself among those who believe that vaccines have had little or
nothing to do with any overt disease declines. However, I
also think that like claims of safety, claims of vaccine-effectiveness
are considerably overblown and understudied (more on these points in
And while there are many criticisms that can be made about such
wide-reaching claims of effectiveness, some of which have been touched
upon in previous
Scandals, it is an argument
often made against them being effective that I would like to take issue
with at this time.
It is widely known that a certain percentage of vaccines fail,
whether due to "primary
vaccine failure" (i.e., the vaccine never worked in the first
place) or "secondary vaccine failure" (waning
immunity). It is also true that outbreaks have occurred in
vaccinated populations, including at least one population in
Thus no one is arguing that vaccines are 100% effective.
So what happens when an outbreak occurs, and there are vaccinated
involved? Instead of noting that, of course, the vaccine doesn't
always work, claims are made that this means the vaccine is ineffective.
And in a mostly vaccinated population, if most of the cases are
vaccinated? Well, instead of noting that, of course, in highly
vaccinated populations most of the cases will usually have been
vaccinated, there is almost a feeding frenzy over how ineffective the
It is to be expected that there will be more cases among the
vaccinated in a highly vaccinated population. But so what?
Was the vaccine effective most of the time, some of the time, or almost
Making too much of the mere fact that there are outbreaks involving
the vaccinated, drawing simplistic inferences about vaccine
effectiveness without including critical information, detracts from
legitimate discussion of vaccine effectiveness.
Vaccines are not perfect. The simple fact that outbreaks occur and
the vaccinated can be counted among the cases, even if they constitute
a majority of them, does not in and of itself constitute proof that
vaccines are ineffective. It just proves they are less than 100%
And everybody already knows that.
There are viable arguments which can be made about and against
vaccine-effectiveness. But the mere fact that a vaccinated
population, and in particular a highly vaccinated one, can result in
cases among the vaccinated is not one of them.
"Eternal vigilance is
the price of liberty." - Wendell Phillips (1811-1884), paraphrasing
John Philpot Curran (1808)