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> Wild polioviruses are classified as risk group 2. The rationale for the minimal biosafety levels is the near universal immunization of the population with OPV and/or IPV.
Biosafety Level 2 (BSL-2) is the currently recommended minimal standard for all countries. To ensure safe handling of wild polioviruses and potentially infectious materials as eradication nears (Pre-Eradication), BSL-2, hereafter referred to as BSL-2/polio, should be enhanced by specific practices described in this document
(Box 10).