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Yeah this is a known thing. That's why we don't vaccinate against polio but try to keep it out of the country.

The US still vaccinates against polio, but we don’t use the OPV anymore: https://www.cdc.gov/vaccines/vpd/polio/index.html

The OPV is still used in the few countries where there is polio in the wild because it does have advantages over the IPV.

Ah yes, thanks for the clarification.