You don't need to read this to know flu season is in flux; the flu has a pretty solid PR strategy — it more or less invented viral campaigning.

Nor do you need a reminder that some folks deny and oppose the practice of vaccination. But you may not know, vaccine deniers have been around as long as vaccines themselves. Shortly after Edward Jenner developed a vaccine for smallpox in 1796, detractors assailed the newfangled, untested, and suspect emergence of vaccines. Unlike the evolution of vaccines, not much has changed in the criticism.

In an 1802 caricature illustrated by satirist James Gillray for the "Publications of the Anti-Vaccine Society," a calm Jenner is shown vaccinating smallpox via cowpox to apprehensive patients. Rumors alleging that the vaccinated would grow bovine features are manifest as fact, while a mixture of the vaccine is shown next to a vial of vomit. Depictions like so reflected the public's skepticism in treatments that sound dangerous in spite of their experimentally-calibrated safety and effectiveness.

And much of that is understandable. For centuries up to this point, smallpox was a leading cause of death for a tremendous amount of the population. To then see a cure come onto the scene that involved inflicting its patient with a like form of deadliness did warrant some concern. It's difficult to explain in the parlance of science why something works when everything in your lived experience suggests otherwise.

Where early criticism was directed to the institution of science, a much stronger resistance formed against the government following compulsory vaccination acts passed by the British Parliament between 1840 and 1853. After years of pressure, anti-vaccinators succeeded in modifying these acts to include exemptions for conscientious objectors in 1898. (It's these laws, not military drafts, that introduced the concept into law.) In the early 1900s, the British Medical Journal documented notes from physician groups frustrated that their marked success in reducing disease was failing to defeat the “pamphlets, tracts, and leaflets” of vaccine skeptics.

Modern criticisms follow from the thread of history to take three flavors. A libertarian response seeks refuge from the unwarranted intrusions of government in the name of civil liberty. A pseudoscientific response ties the practice of vaccination to the proliferation of other problems, most commonly autism. Finally, the anecdotal-unimpressed response alleges that some people still get sick, so flu vaccines are ineffective.

Generally we can dismiss and avoid deniers, critics, and skeptics as quacks (see climate change). The problem with the anti-vaccine tribe is that they actively generate a less healthy world; their exemption thwarts the model of vaccination. Vaccines, especially in their modern deployment against the flu, depend on the inoculation of a critical mass. In a classroom of 20 children, if one child gets the flu because his or her parents are vaccine skeptics, the rest of the class' inoculation is moot. By not vaccinating, this is a skepticism made more salient by the practice of skepticism itself.

That both vaccines and deniers have been around for 210 years does not mean they're on the same footing. Diphtheria, measles, mumps, and rubella have all been made memories by vaccines. Smallpox was eradicated by the 1970s. Polio is on the same path. On the other hand, we're seeing the same arguments from skeptics, plus or minus some new colloquialisms and an amplifying media. It tends to be the case that controversy bends to the will of history. We can only hope the same will be true here. After all, you know what else was controversial in the 1800s? Slavery. You should get that flu shot.