Vaccine-derived polio in Peru after 32 years of elimination: reflections on the routine childhood immunisation coverages

Abstract

After 32 years of polio elimination in Peru, six sporadic cases of vaccine-derived poliovirus (VDPV) have been reported between 2003 and 2011 in urban and periurban settings. On 21 March 2023, a new case was confirmed in a one-year-old indigenous male infant resident of the district of Manseriche, Loreto region, located in a remote area in the north-eastern Peruvian jungle. The patient developed fever, cough, and weakness in the lower limbs, and had not received any previous vaccinations. Therefore, a sample was taken and sent to the Oswaldo Cruz Institute (FIOCRUZ) from Brazil, given the absence of PCR and genomic tests for polio in Peru. A type 1 VDPV was detected...