I was somehwat up on this at one point when I was a Rotary member, as Rotary's main initiative is polio eradication.
The problem with the live-virus oral polio vaccine (OPV) and vaccine-associated paralytic poliomyelitis (VAPP) has been discussed for quite some time in public health circles. Contrary to what you seem to be implying, though, the number of polio victims, even accounting for the elevated risk, has been massively lower than the alternative.
However, there is an inflection point where risk of wild polio virus (WPV) cases does not justify the risk of the live-virus OPV and the super aggressive repeated vaccinations that are called for when facing a massive epidemic, and that is the problem that the paper you cite is addressing (and it is a real problem).
It's a risk/benefit calculation, not a verdict on whether live-virus OPV is harmful or helpful to humanity (immeasurably helpful on net) and does not apply to the IPV vaccine, which is not associated with these problems (to my knowledge).
Also, keep in mind, these are not 491,000
additional cases. The net is still massively lower with OPV vaccination than with no vaccination. The question is when you reach crossover for whether OPV is doing more good than
IPV (not than no vaccine, which is not even up for debate, I'm sorry). For some years, people have been saying India has/had finally reached that point. But it asbolutely, definitely, was NOT there when Rotary and Gates began pouring money in to help bring the hyperepidemic under control.
This is much different from saying that the polio vaccine is bad or even that the OPV is bad.
- the polio vaccine used in India during the period is the OPV, a live-virus, but attenuated, form of polio. It most certainly carries more risks, but is more effective, than the inactivated polio virus (IPV) that is used to maintain herd immunity in other places, like the US (and presumably the UK) since 2000. It's a question of risk/benefit. The mechanism is not certain, but it appears that the doses may be so high in India that even the attenuated form can colonise the gut and possibly then mutate and pass to others. It's a real public health issue, no question.
- At least as early as 2013, the WHO called for beginning a transition away from the OPV to the IPV vaccine as worldwide incidence of polio decreases (as I mentioned, in the US and countries where polio was considered eradicated, this took place around 2000).
- this study studies pulse vaccination where kids are getting 8-10 doses of live virus, compared to the 3 doses plus booster of inactivated virus that kids get in countries where polio is considered controlled or eradicated. After 2004, it was common in India to conduct 10 nationwide rounds of vaccination in a single year.
- India was, at the time this started, "hyperepidemic" and accounted for 60% of all polio cases in the world.
- Before this started, India saw 500-1000 cases of paralysis and death EVERY DAY due to polio.
For the 491,000 people who appear to have been afflicted in India due to the vaccine between 2000 and 2017, you have to stack that up against the 500-1000 cases daily in 1999. If you look at what the toll of that would have been, you get 3.3 million to 6.6 million cases. Also, you have to remember that those millions of cases are lower than might be since already before the all-out effort, a lot of Indians were being vaccinated, not just in the incredible numbers at the aggressive doses you see after 1999 (147,000,000 doses given out in a single day once).
The point of that paper is not that polio vaccination is bad, and definitely not a net ill, but that the hyper-aggressive pulse vaccination program with live virus is no longer warranted in India as the disease is no longer hyper-epidemic in India and that vaccine practices should transition to practices similar to in nations where polio is under control because, at a certain point, you hit crossover where the additional protection provided by live-virus is offset by the additional risks and the net number of polio cases is higher with OPV than with IPV vaccines.
Eradicating poliomyelitis: India's journey from hyperendemic to polio-free status (2013)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3734678/The conclusion in the abstract of the above paper gives a nice summary (WPV = wild polio virus)
Elimination of WPVs with OPV is only phase 1 of polio eradication. India is poised to progress to phase 2, with introduction of inactivated poliovirus vaccine (IPV), switch from tOPV to bOPV and final elimination of all vaccine-related and vaccine-derived polioviruses. True polio eradication demands zero incidence of poliovirus infection, wild and vaccine.
Oral polio drops linked to paralysis in Indiahttps://www.scidev.net/asia-pacific/disease/news/oral-polio-drops-linked-to-paralysis-in-india.htmlObjective 2: Immunization systems strengthening and OPV withdrawalhttp://polioeradication.org/wp-content/uploads/2016/07/PEESP_CH6_EN_US.pdfhttp://polioeradication.org/who-we-are/strategic-plan-2013-2018/Vaccine-associated paralytic poliomyelitis in India during 1999: decreased risk despite massive use of oral polio vaccinehttps://www.who.int/bulletin/archives/en/80(3)210.pdfObjective Vaccine-associated paralytic poliomyelitis (VAPP) is a rare but serious consequence of the administration of oral polio vaccine (OPV). Intensified OPV administration has reduced wild poliovirus transmission in India but VAPP is becoming a matter of concern....
Data from the acute flaccid paralysis (AFP) surveillance system in Latin America showed an estimated VAPP risk of 1 case per 1.5–2.2 million doses administered in 1989–91 (6). These studies demonstrated that the risk was substantially increased following receipt of the first dose of OPV and that children with B-cell immunodeficiency disorders were at highest risk for VAPP
https://en.wikipedia.org/wiki/Pulse_Poliohttps://www.webmd.com/children/vaccines/polio-vaccine-ipv#1https://web.archive.org/web/20070929090612/http://www.immunize.cpha.ca/english/consumer/consrese/pdf/Polio.pdfAnd for another reference:
The Economist article you link to:
The tally for 2018 shows a dramatic swing: 98 cases of vaccine-derived polio; 29 cases of the wild version. What is vaccine-derived polio?
Wikipedia
At its peak in the 1940s and 1950s, polio would paralyze or kill over half a million people worldwide every year
https://en.wikipedia.org/wiki/History_of_polio
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