The situation with polio in the world in 2023

Content
● Introduction (see). ● Poliomyelitis caused by wild type 1 virus (see). ● Poliomyelitis caused by viruses obtained from vaccines (see). ● General overview of countries with polio cases in the last 12 months (see). ● Polio eradication is feasible (see). ● Additional information, links and recommended links (see).

In other words

● The final global polio situation for 2023 is presented in diagrammatic form. ● In 2023, 6 cases of wild poliovirus type 1 (VP1) were reported in Afghanistan and another 6 in Pakistan, all in the border regions between both countries. In the previous year, 2022, there were 2 cases in Afghanistan, 20 in Pakistan and 8 in the non-endemic country of Mozambique. ● In 2023, a total of 373 cases caused by vaccine virus type 2 (VPdv2) were reported in 22 countries, and a further 133 cases caused by vaccine virus type 3 (VPdv3) in three countries. In the previous year, 2022, there were 689 and 193 cases, respectively. ● Elimination of wild-type VP1 infections is feasible. ● Eradication of polio caused by circulating vaccine-derived viruses is extremely difficult, and a new oral vaccine has been developed and is expected to help achieve this goal.

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Introduction

Final data on status of polio in the world in 2023to conclude two notes previously published on this site:

The data shown schematically in the four figures are taken from Global Polio Eradication Initiative (GPEI).

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Poliomyelitis caused by wild type 1 virus

• In 2023, 6 cases of wild poliovirus type 1 (VP1) were reported in Afghanistan and another 6 in Pakistan, all in the border regions between both countries (their common border is about 2600 km).
• The cases in Pakistan involved people previously vaccinated with the oral vaccine.
• The cases, which affected areas of Afghanistan where there had been no cases in previous years, occurred in areas where door-to-door vaccination was prohibited by local authorities.
• In the previous year, 2022, there were 2 cases in Afghanistan, 20 in Pakistan and 8 in the non-endemic country of Mozambique.

elimination of VP1 infections wild is a possibility, but vaccination efforts only need to be stepped up in the two endemic countries (see image above).

Vaccination coverage in the second year of life is estimated to be 76% with three doses of bivalent oral vaccine in Afghanistan in 2022, and 71% with one dose of inactivated vaccine (Bjork A, MMWR Morb Mortal Wkly Rep, 2023).

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Poliomyelitis caused by vaccine-derived viruses

• In 2023, a total of 373 cases caused by vaccine-derived virus type 2 (VPdv2) and an additional 133 cases caused by vaccine-derived virus type 3 (VPdv3) were reported.
• In the previous year, 2022, there were 689 and 193 cases, respectively.
• Cases of HPd2 have been reported in 22 countries, 19 of them on the African continent (the rest in Indonesia (6 cases), Yemen (4) and Israel (1)). In 2022, this will affect 20 countries.

End polio cases caused by circulating vaccine-derived viruses is extremely difficult, and the introduction of a new oral vaccine against type 2 virus (nVPO2) is aimed at strengthening the fight against polio in countries affected by outbreaks caused by VPdv2, primarily on the African continent. The development of versions similar to the new type 1 virus vaccine is currently being explored as a possible treatment for outbreaks caused by VPdv1. And all this without neglecting national vaccination programs, which include the use of trivalent inactivated vaccines and bivalent oral vaccines, which are the mainstay of the fight to eradicate polio.

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Overview of countries with polio cases in the last 12 months

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Eradication of polio is possible

eradication of polio is possiblebut vaccination (which is necessary to maintain, expand and strengthen) is only part, albeit an extremely important one, of the solution.

Eliminating the use of all attenuated oral vaccines will be a solution that will need to be considered in the coming years (as these vaccines are currently both the solution and the source of the problem).

Improving transmission control conditions, including safe water distribution infrastructure, epidemiological surveillance and other measures, requires the cooperation of the international community and the stability of affected regions.

Once the goal of polio eradication is achieved, this story will not end, but a period of management will begin to ensure the eradication of all polioviruses.

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More information on this website

Links and recommended links

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