Pesticides as the cause of polio

As told: polio was never an infectious disease. Paralysis rates rose and fell in step with agricultural pesticide use — lead arsenate from the 1890s, DDT from 1945 — and the summer peak of polio matched the spraying season, not any pattern of contagion. On this account the vaccine arrived just as pesticide use was being curtailed, and took credit for a decline it did not cause. A stronger version adds that the diagnostic category itself was quietly redefined after 1955 so that cases which would once have been counted as polio were recorded as aseptic meningitis or Guillain-Barre instead.

Morton Biskind, a physician writing between 1949 and 1953, argued that DDT poisoning was being misdiagnosed as polio and pressed the case in medical journals and before Congress. The argument was largely dormant for decades until Jim West assembled the pesticide-production and paralysis charts in the late 1990s, and Suzanne Humphries carried it into the modern vaccine-critical movement through the book Dissolving Illusions. It circulates now mostly as a pair of overlaid graphs.

Paraphrased summaries of publicly circulating reports, not verbatim quotes from identified individuals. Unverified by definition.

• “A poster who found the pesticide-production and paralysis charts describes it as the moment the official history stopped making sense to her, and says she has since declined the polio component for her children.”

  no changeReported 2021

  Paraphrased from publicly circulating accounts. Records a change in behaviour, not a health outcome.

• “A retired farmer's account describes his brother's paralysis in the summer of 1952, weeks after crop dusting near the family land, and his lifelong conviction that the spraying and not any virus was responsible. He notes that no doctor at the time asked about pesticide exposure.”

  no changeReported 2016

  Paraphrased from publicly circulating recollections shared in vaccine-critical forums. Unverified.

The correlation is real, and it is the reason the theory persuades people: polio was seasonal, it peaked in summer alongside spraying, and DDT is genuinely neurotoxic. What the theory has to account for and does not is that poliovirus was isolated from patients in 1908 and grown in culture by 1949, that transmission was demonstrated experimentally, and that the 1954 Francis field trial randomised roughly 1.8 million children — placebo controls in that trial developed paralytic polio at nearly three times the rate of the vaccinated arm, in the same towns, in the same summer, under the same spraying. Pesticides cannot explain a difference that tracks who received an injection. The 1955 case-definition change is documented and did tighten reporting, but it postdates the trial it is invoked to explain away. Countries that never used DDT heavily had polio epidemics; the disease has since been eliminated from regions where pesticide use rose rather than fell.