Apparently, it does, as indicated by this CDC report. Please tell me I'm wrong If I'm reading this incorrectly, but it seems to be saying that the Polio vaccine can prevent, AND CAUSE, polio. https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5638a3.htm
There were too many terms for me to follow along with the article, so it's beyond me. But, that said, I heard decades ago that there are two polio vaccines. One that's made with dead polio, which is safe, and one that's made with living polio specimens, which can sometimes cause polio instead of preventing it. Closer to the current day, I hear that militant terrorists are spreading diseases like polio back into areas and warzones that were previously free of polio because they eradicated it in the past.
There have been cases of people contracting polio who have not been inoculated themselves by changing babies diapers for example who were inoculated with live vaccine. It can be expected that polio and measles could make a comeback as many vaccination programs throughout the world wither due to the focus on c-19. The fact that measles has an R0 factor of about 15 while c-19 never rises above three is rather frightening.
Only indirectly. A person who in immunised can excrete live virus which in rare cases has the potentially to trigger an actual polio outbreak if the wider community has poorly vaccine take-up. It's only actually happened a handful of times and is massively outweighed by the almost irradiation of polio vaccination programs have achieved. https://en.wikipedia.org/wiki/Polio_vaccine#Vaccine-induced_polio
Only in third world countries (and China which is a second rate country) not in the U.S. Sounds like a quality control problem.
As I recollect the excreted virus mutates enough to not be Here is a direct quote from the latest issue of the Economist Espresso dated 25 Aug 2020 "An independent health commission originally appointed by the World Health Organisation is today expected to declare that Africa has eradicated polio. This, however, does not mean the disease has stopped paralysing African children. The polio virus is now endemic in only two countries, Afghanistan and Pakistan. But more than 20 countries, mostly in Africa, have harmful mutations of the virus in the oral polio vaccine. The vaccine-virus, a neutered version of the original bug, is excreted for a time after oral vaccination. It can be picked up—and passed on further—by anyone who is not vaccinated. If this chain of transmission lasts for more than a year, the vaccine-virus can mutate its way into a paralysing form. The disruption to routine childhood vaccination in developing countries caused by the covid pandemic is creating fertile ground for such mutations—and for the spread of the virus from Pakistan and Afghanistan. The end of polio may not be as close as it seems."
