India switched from tOPV to bOPV in April 2016. The primary reason for this switch was:
- A bOPV is more thermostable and cheaper to produce
- B Wild poliovirus type 2 was eradicated globally (2015); continued Sabin type 2 in tOPV risked cVDPV2 emergence ✓
- C bOPV provides superior seroconversion for all three poliovirus serotypes
- D tOPV caused more Vaccine-Associated Paralytic Poliomyelitis (VAPP) than bOPV
Correct answer: B. Wild poliovirus type 2 was eradicated globally (2015); continued Sabin type 2 in tOPV risked cVDPV2 emergence
Explanation
Wild poliovirus type 2 was certified eradicated in 2015. Continuing tOPV (Sabin types 1+2+3) risked generating circulating vaccine-derived poliovirus type 2 (cVDPV2) outbreaks from the replicating Sabin 2 component. The April 2016 globally synchronized tOPV-to-bOPV switch (types 1 and 3 only) removed Sabin 2 from routine immunization, directly reducing cVDPV2 risk while maintaining protection against wild poliovirus types 1 and 3.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.