"Herd" immunity is a theory which purports to explain how an entire
group can be protected from disease. It is thought to result in
protection of everyone once a magic percentage of vaccinated or
otherwise immune individuals is reached, by preventing transmission of
the virus to those who remain "unprotected", either because a vaccine
didn't happen to work for them, or was too risky in their case.
It relies on getting as high a percentage vaccinated as possible,
which means requiring that everyone who doesn't have an obvious
contraindication to getting a vaccine, be vaccinated.
However, it is ironic and worth noting that it is the failure of
vaccination, not its success, which is used as justification for
requiring its use. Thus, children attending school are required
to get vaccinations, whether their parents want them to or not, whether
it is personally good for them or not, simply because vaccination
doesn't always work. This, all in the name of "herd
Notwithstanding the questionable validity of using the weakness of a
product as justification for forcing it on people (more on that another
time), and whether or not there is any justice in forcing someone to
potentially sacrifice their own health in order to "protect" someone
else's, there seem to be problems with the theory itself, i.e.,
the notion that if you reach a high enough percentage that is
vaccinated, a "herd immunity" will result.
One of those potential problems is that
outbreaks have occurred in highly vaccinated populations, including
those documented to be 100% vaccinated.
If the "herd" cannot be protected with 100% vaccination rates, maybe
there is something wrong with the theory.
Another possible problem is that vaccines often do not prevent
transmission, instead merely preventing full-blown cases of disease
or subclinical cases). In fact, circulating virus is known to
the immunity of the vaccinated (and perhaps even those
immune), thereby prolonging the apparent effectiveness of
the vaccine (and maybe even natural immunity). In the
of circulating disease, vaccine-induced immunity is more likely to
wane, and boosters will be required. In any event, it is hard to
understand how something which does
not necessarily prevent transmission can result in immunity for the
Is the notion of "herd immunity" scientifically valid?
If circulation of disease cannot always be prevented by
vaccination, and instead merely drives it underground in the guise of
mild or subclinical cases, can "herd immunity" be counted on to work?
Is one of the reasons outbreaks have occurred in highly
vaccinated populations because vaccines are not as effective as we have
been led to believe? Are the methods currently used to
measure/determine immunity inadequate or flawed?
How valid is the justification for mandating vaccination, given
what appears to be some evidence against the theory used to support