Vaccine-derived poliomyelitis in Nigeria.
D002675:Child, Preschool; D004196:Disease Outbreaks; D006801:Humans; D009549:Nigeria / Q000453:epidemiology; D011051:Poliomyelitis / Q000139:chemically induced* / Q000453:epidemiology; D011055:Poliovirus Vaccine, Oral / Q000009:adverse effects*
D011055:Poliovirus Vaccine, Oral