Have there been negative large-scale long term effects from vaccines?

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It pains me to give the antivaxxers the slightest ammunition, but an example of a vaccine that can have long-term, negative effects some time after it has been administered is the Oral Polio Virus.

A potential, adverse effect of the OPV is its known ability to recombine to a form that causes neurological infection and paralysis. This genetic reversal of the pathogen to a virulent form takes a considerable time (at least 12 months) and does not affect the person who was originally vaccinated. The vaccine-derived attenuated virus is normally excreted from vaccinated people for a limited period. Thus, in areas with poor sanitation and low vaccination coverage, the spontaneous reversal of the vaccine-derived virus to a virulent form and its spreading in the environment can lead to unvaccinated people becoming infected.

John Kolmer's 1935 polio vaccine was given to ten thousand children, five of these died of polio and 10 more were paralysed, usually in the arm where the vaccine was injected

Even Jonas Salk's polio vaccine could cause problems, though this was because of poor preparation. The Cutter Incident was due to live virus being allowed to contaminate the vaccine.

In spite of these problems, the vaccines have hugely reduced the deaths and disabilities caused by polio. In 1952, a polio epidemic in the USA caused 58,000 cases including 3,145 deaths and 21,269 cases of paralysis. The USA has been free of polio since the 1960s

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