The SV40 virus was unintentionally introduced into humans through contaminated polio vaccines derived from rhesus macaque cells, raising concerns about its oncogenic potential. Despite efforts to eradicate polio, new vaccine-derived poliovirus strains and prolonged viral shedding have complicated vaccination efforts and led to a rise in acute flaccid paralysis cases. Alternative vaccination strategies utilizing monovalent and bivalent vaccines are being implemented to increase effectiveness and control the disease.