Immunization, Vaccines and Biologicals

Replacing trivalent OPV with bivalent OPV

A critical step in polio eradication


Objective 2 of the Polio Eradication and Endgame Strategic Plan 2013-2018 calls for an important transition in the vaccines used to eradicate polio and requires the removal of all oral polio vaccines (OPVs) in the long term. This will eliminate the rare risks of vaccine-associated paralytic polio (VAPP) and circulating vaccine-derived poliovirus (cVDPV).

The withdrawal of OPVs began in April 2016 with a switch from trivalent OPV (tOPV) to bivalent OPV (bOPV), removing the type 2 component (OPV2) from immunization programmes.

Background information

The following core materials provide an overview of the importance of the switch and its role in hastening the interruption of all poliovirus transmission.

OPV Switch - An Introductory Powerpoint

OPV Switch - Frequently Asked Questions (long version)

OPV Switch - Frequently Asked Questions (easy version)

OPV Switch - Quick reference summary

For more information on the switch from tOPV to bOPV, please see pages:

Please let us know if you have additional questions that are not covered through this site by emailing

Related links