polio vaccines are made from weakened or dead polio viruses and may themselves undo eradication.
First, the inactivated/killed polio vaccine cannot come back to life. Second, that risk for the attenuated vaccine is well known.
Eradicating polio may offer permanent benefits
Will.
You can disagree as to whether the benefits are worth the costs, of course. And perhaps finite problems can be analyzed within the usual framework—but I wanted to bring them up.
No, may. Even if you have zero known cases, you have not eradicated polio for sure because of the carriers and natural reservoirs and obscure little hidden villages. So you still need vaccines. And your own links point out that the attenuated vaccine can still be infectious!
This is believed to be a rare event, but outbreaks of vaccine-associated paralytic poliomyelitis (VAPP) have been reported, and tend to occur in areas of low coverage by OPV, presumably because the OPV is itself protective against the related outbreak strain.
To quote from one of the references:
The rate and pattern of VP1 divergence among the circulating vaccine-derived poliovirus (cVDPV) isolates suggested that all lineages were derived from a single OPV infection that occurred around 1983 and that progeny from the initiating infection circulated for approximately a decade within Egypt along several independent chains of transmission.
Correcting factual errors:
Neither does polio. “Some diseases have no non-human reservoir: poliomyelitis and smallpox are prominent examples.”
First, the inactivated/killed polio vaccine cannot come back to life. Second, that risk for the attenuated vaccine is well known.
Will.
You can disagree as to whether the benefits are worth the costs, of course. And perhaps finite problems can be analyzed within the usual framework—but I wanted to bring them up.
No, may. Even if you have zero known cases, you have not eradicated polio for sure because of the carriers and natural reservoirs and obscure little hidden villages. So you still need vaccines. And your own links point out that the attenuated vaccine can still be infectious!
To quote from one of the references:
What is a “contaminated natural source”? I am genuinely curious.
A variation on natural reservoir.