Several articles in the news including the one in Quanta [1,2,3] appear to have caused some misunderstanding. What is clear so far is that “circulating vaccine-

Several articles in the news including the one in Quanta [1,2,3] appear to have caused some misunderstanding. What is clear so far is that “circulating vaccine-derived polioviruses (cVDPVs) can emerge in settings with low population immunity...,” therefore, “all countries must maintain high population immunity.” [4] It was found that “compared with January 2017–June 2018, the number of reported cVDPV outbreaks more than tripled, from nine to 29,” in the most recent survey. [4] As a result, the Global Polio Eradication Initiative” is planning future use of a novel type 2 OPV, stabilized to decrease the likelihood of reversion to neurovirulence.” One of the most significant barriers to polio eradication is “reaching every child – including inconsistent campaign quality, insecurity, conflict, massive mobile populations, and, in some instances, parental refusal to the vaccine.”[5] It is false to say that somehow cVDPVs had been kept a secret or their importance downplayed. [6] There are critical reasons to remain vigilant of any adverse consequences but keep in mind that every year “hundreds of thousands of cases due to wild polio virus are prevented. Well over 10 million cases have been averted since large-scale administration of OPV began 20 years ago.” [7] [1] https://www.quantamagazine.org/why-smallpox-is-no-more-but-polio-and-other-diseases-persist-20191203/ https://www.quantamagazine.org/why-smallpox-is-no-more-but-p... [2] https://www.nytimes.com/aponline/2019/11/25/health/ap-af-med-africa-polio.html https://www.nytimes.com/aponline/2019/11/25/health/ap-af-med... [3] https://www.washingtonpost.com/world/africa/more-polio-cases-now-caused-by-vaccine-than-by-wild-virus/2019/11/25/1a4d087e-0f76-11ea-924c-b34d09bbc948_story.html https://www.washingtonpost.com/world/africa/more-polio-cases... [4] https://www.cdc.gov/mmwr/volumes/68/wr/mm6845a4.htm https://www.cdc.gov/mmwr/volumes/68/wr/mm6845a4.htm [5] http://polioeradication.org/news-post/global-leaders-pledge-us2-6-billion-to-eradicate-polio-at-the-reaching-the-last-mile-forum-in-abu-dhabi/ http://polioeradication.org/news-post/global-leaders-pledge-... [6] https://www.ncbi.nlm.nih.gov/books/NBK236293/ https://www.ncbi.nlm.nih.gov/books/NBK236293/ [7] https://www.who.int/features/qa/64/en/ https://www.who.int/features/qa/64/en/