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With the COVID-19 pandemic abating, the only remaining Public Health Emergency of International Concern is polio [1]. Remarkable progress has been made in reducing the global burden of poliomyelitis since the establishment of the Global Polio Eradication Initiative (GPEI) in 1988. However, achieving and sustaining eradication of all forms of polioviruses is being compromised by two sources of paralytic poliomyelitis: persisting pockets of type 1 wild poliovirus transmission in Afghanistan and Pakistan which reported 6 cases each in 2023 [2] and ongoing outbreaks of circulating vaccine-derived polioviruses (cVDPV)[3]. The latter, particularly those arising from type 2 Sabin oral polio vaccine (OPV) strains, have outnumbered cases of wild-type polio over the last few years, mostly due to outbreaks in the WHO African Region which affected 28 different countries in 2023 [4]. Sabin OPVs, in monovalent (mOPV) or trivalent (tOPV) forms, induce robust humoral and intestinal immunity, but while passing through the vaccinee’s intestine can lose their attenuations and in rare cases can revert to neurovirulence. In settings of persistently poor immunity and low levels of sanitation and hygiene, such reverted OPV strains can establish person-to-person circulation and cause paralytic outbreaks [5]. This risk is more prominent with type 2 poliovirus given there is limited mucosal immunity against this serotype of polio in young children following the 2016 global switch from tOPV (types 1, 2 and 3) to bivalent (types 1 and 3) OPV in essential immunization schedules [6, 7]. To mitigate the risk of cVDPV and vaccine-associated paralytic poliomyelitis (VAPP) and …