How many times have you heard tiresome tropes about the HPV vaccine causing this or that? No matter how many times we debunk the nonsense, it persists. One of the critical points I try to make is that before an anti-vaccine claim can be made, there has to be a biological plausibility. That is, can we establish a reasonable and plausible biological mechanism, without resorting to special pleading and pseudoscience, that can lead one from one action, say receiving a vaccine, to some result, real or imagined.
Biological plausibility is a requirement to establish that correlation means causation. It is almost an essential requirement for one to claim a causal association. But biological plausibility must be consistent with our existing knowledge of biology, chemistry, physics, and medicine. How many times has an anti-vaccine zealot tried to convince us that “mercury in vaccines causes autism” but ignores the basic scientific tenets of numerous fields of biomedicine like biochemistry, cell biology, toxicology, immunology, neurology – well, just about every field?
Or someone who claims that acupuncture treats a bunch of diseases, yet we cannot find any reasonable biological plausibility between sticking a needle in the arm to treating some medical condition like pain. They tend to ignore that by using their own personal anecdote as “proof.”
That’s why science is much harder than what is said by the pseudoscience pushers. Establishing plausibility requires a strong knowledge of science to make the case. It’s much more than simply stating that plausibility does exist, you have to use actual real science, published in real scientific journals, to make the case.
So let’s talk a little bit about causality. And a large dose of biological plausibility. Continue reading “Biological plausibility – a keystone of medical and vaccine research”