WHO global initiative: Poliomyelitis eradication
A world without poliomyelitis: The WHO, with its global initiative, is pursuing this objective. High vaccination rates, constant monitoring and safe handling of polio viruses in laboratories are the key elements in the worldwide eradication of poliomyelitis.
In 1988, the World Health Assembly adopted Resolution WHA41.28, thereby launching the Global Polio Eradication Initiative (GPEI).
Since then, the global number of cases has decreased by more than 99%, from an estimated 350,000 new cases per year. Whereas wild poliovirus used to be endemic in more than 125 countries, it now circulates only in Afghanistan and Pakistan.
Polio eradication is considered achieved when no new cases caused by wild polioviruses occur worldwide for three consecutive years, surveillance systems demonstrate sufficiently high sensitivity, and all laboratory stocks are managed under strict containment conditions.
Five WHO regions are currently certified as polio-free: the Americas (1994), the Western Pacific (2000), Europe (2002), South-East Asia (2014), and Africa (2020).
Global Eradication of Wild Poliovirus Types 2 and 3
Wild poliovirus type 2 (WPV2)
The last WPV2 case occurred in 1999. WHO declared WPV2 globally eradicated in September 2015. To prevent re-emergence, the Sabin type 2 strain was globally withdrawn from the oral live polio vaccine (OPV) in April 2016. Attenuated vaccine strains may be genetically unstable and, in rare cases, mutate back to neurovirulent forms. This can lead to so-called circulating vaccine-derived polioviruses (cVDPVs), which may spread in under-immunized populations and cause clinical cases.
Wild poliovirus type 3 (WPV3)
The last WPV3 case was reported in Nigeria in 2012. On 24 October 2019, the WHO declared WPV3 globally eradicated.
Containment After Eradication
Since the eradication of poliovirus types 2 and 3, strict global requirements have been in place for the containment of remaining virus stocks. Wild polioviruses, vaccine-derived viruses, and potentially infectious material (PIM) may therefore only be stored in specially certified facilities known as Poliovirus-Essential Facilities (PEFs). Facilities without such certification are required either to destroy these samples or to transfer them to a PEF.
The same requirements apply to the Sabin type 2 vaccine strain, as this virus type is no longer used in the oral polio vaccine and any re-emergence must be prevented. In contrast, the Sabin type 3 vaccine strain may temporarily continue to be used in non-certified facilities as long as the bivalent oral polio vaccine (OPV1 and OPV3) remains in use worldwide.
Following the eradication of WPV1, the same requirements will apply to all remaining poliovirus type 1 materials.
National Poliovirus Containment Coordination Body
The Biosafety, Human Genetics and Reproductive Medicine Section of the Federal Office of Public Health (FOPH) serves as the national coordination body responsible for the controlled handling and safe containment of polioviruses in Swiss laboratories. In collaboration with cantonal authorities, it ensures strict compliance with the WHO Global Action Plan for Poliovirus Containment, 4th edition (GAP IV, see under documents). GAP IV has been in force since 1 July 2022 and has fully replaced the 3rd edition (GAPIII, 2014/2015). It constitutes the globally binding framework for all facilities handling or storing poliovirus materials.
Also binding is the WHO PIM Guidance, 2nd edition (October 2024): “Guidance to minimize risks for facilities collecting, handling or storing materials potentially infectious for polioviruses” (see under documents). This document is not only intended for specialized polio laboratories but for all facilities — including hospitals, environmental laboratories, and biobanks — that may possess and/or handle PIM, such as stool samples, wastewater samples, or respiratory specimens, without knowing whether they contain polioviruses. The 2nd edition includes updated web annexes (A–D), including a country- and territory-specific poliovirus data inventory (Web Annex A) and revised reporting forms (Forms 1 and 2, see under documents).
Core Tasks of the National Coordination Body
- Inventory: Identification of all Swiss laboratories holding wild polioviruses, live attenuated polio vaccines (OPV/Sabin), vaccine-derived polioviruses , or potentially infectious material
- Containment of WPV2 and WPV3: Ensuring that these eradicated strains are either stored exclusively in certified PEFs or have been destroyed
- Preparation for WPV1 containment: Coordinating preparatory activities for the future containment of all remaining WPV1 materials following successful eradication, in accordance with GAP IV Phase III.
For questions regarding the containment of polioviruses, please contact biosafety@bag.admin.ch.
Further information
Index
Further Topics
Poliomyelitis (polio)
While the global health community is now close to eradicating poliomyelitis (often referred to as polio) worldwide, this objective has not yet been achieved. As a result, polio vaccinations are still required in countries now free of the disease; and booster vaccinations in adulthood may also be recommended before travel to certain destinations.
Biosafety
Biosafety aims to protect people and the environment when genetically modified, pathogenic or alien organisms are handled.
Federal Office of Public Health FOPH
Biosafety, Human Genetics and Reproductive Medicine Section
Schwarzenburgstrasse 157
Switzerland - 3003 Bern