WHO Prequalifies New nOPV2 Vaccine to Strengthen Polio Eradication

Novel Oral Polio Vaccine Type 2 Cleared for Global Immunisation Campaigns

The World Health Organization (WHO) has prequalified another novel oral polio vaccine type 2 (nOPV2) , reinforcing global initiatives aimed at eliminating poliomyelitis. This approval permits United Nations agencies , including UNICEF, to procure and deploy the vaccine across international immunisation programmes.

WHO prequalification signifies compliance with globally accepted benchmarks of quality, safety, and efficacy , ensuring the vaccine’s suitability for large-scale public health use.

Significance of nOPV2

The nOPV2 vaccine represents a major technological advancement in polio prevention. Unlike earlier oral polio vaccines (OPVs), which occasionally reverted to virulent forms and triggered circulating vaccine-derived poliovirus (cVDPV) outbreaks, nOPV2 has been designed for enhanced genetic stability .

This stability reduces the probability of mutation while preserving the vaccine’s capacity to halt virus transmission. The innovation directly addresses one of the principal challenges encountered during the final phase of global polio eradication.

Global Polio Eradication Strategy

The approval aligns with renewed international commitments, including a $1.9 billion funding mobilisation pledge announced in December. The eradication programme targets the immunisation of nearly 370 million children annually , despite mounting fiscal pressures and competing global health demands.

Although polio has been eradicated in most regions, persistent transmission in limited geographies continues to pose risks of resurgence. Sustained vaccination coverage remains critical to prevent re-emergence.

Public Health Context

Poliomyelitis is a highly infectious viral disease primarily affecting children under five years of age . It can cause irreversible paralysis and, in severe instances, death. Oral vaccines remain central to eradication campaigns due to ease of administration and their ability to generate intestinal immunity , crucial for interrupting transmission.

Exam-Focused Points

• WHO prequalification → Enables UN procurement & global deployment

• nOPV2 → Targets type 2 poliovirus , improved genetic stability

• Key risk addressed → Vaccine-derived poliovirus outbreaks

• Polio impact → Mainly children under five; paralysis risk

• Global target → ~ 370 million children immunised annually