Evolution of poliovirus since introduction of attenuated vaccine.

Cessation of Trivalent Oral Poliovirus Vaccine and Introduction of Inactivated Poliovirus Vaccine - Worldwide, 2016.

Since the 1988 World Health Assembly resolution to eradicate poliomyelitis, transmission of the three types of wild poliovirus (WPV) has been sharply reduced (1). WPV type 2 (WPV2) has not been detected since 1999 and was declared eradicated in September 2015. Because WPV type 3 has not been detected since November 2012, WPV type 1 (WPV1) is likely the only WPV that remains in circulation (1). ...

Introduction of Inactivated Poliovirus Vaccine and Switch from Trivalent to Bivalent Oral Poliovirus Vaccine — Worldwide, 2013–2016

Since the 1988 World Health Assembly resolution to eradicate poliomyelitis (polio), transmission of wild poliovirus (WPV) has been interrupted in all countries except Afghanistan, Nigeria, and Pakistan. No polio cases caused by WPV type 2 (WPV2) have been identified since 1999, and WPV type 3 has not been detected since November 11, 2012. This progress has been achieved through widespread use o...

Experience with production and control of attenuated poliovirus (Subinstrains) in human diploid cells

Introduction of Inactivated Poliovirus Vaccine in National Immunization Program and Polio Endgame Strategy.

The World Health Organization declared India among other 10 countries in South East Region - as 'polio-free' in 2014. Since then, the Government of India (GoI) has scaled up its initiatives against polio endgame which targets virus eradication and sequential withdrawal of type 2 virus from oral polio vaccine (OPV). However, prior to choosing the switch from trivalent OPV (t-OPV) to bivalent OPV...

Improvement in the yield of oral poliovirus vaccine (Sabin strains) produced in human diploid cells