Vaccine Derived Polio Virus (VDPV)
Week [30 November-6 December]
A child in Delhi was diagnosed with the P2 strain of the rare Vaccine Derived Polio Virus (VDPV). The last recorded case of VDPV was reported from Beed, Maharashtra, in 2013. The P2 strain, considered the strongest of the three strains of the polio virus, was the first to be eliminated from India in 1999.
What is vaccine-derived polio?
Oral polio vaccine contains an attenuated (weakened) but live vaccine-virus, activating an immune response in the body. In rare cases, when the child’s immunity is low, the virus can start circulating actively in the body of an immunised child. In areas of inadequate sanitation, excreted vaccine-virus can spread in the immediate community before eventually dying out. On rare occasions, if a population is seriously under-immunised, an excreted vaccine-virus can spread in the immediate community before eventually dying out. On rare occasions, if a population is seriously under-immunised, an excreted vaccine-virus can continue to circulate for an extended time.
Source: WHO