Polio, Angola.
D000810:Angola / Q000453:epidemiology; D002675:Child, Preschool; D006801:Humans; D011051:Poliomyelitis / Q000453:epidemiology* / Q000517:prevention & control; D011055:Poliovirus Vaccine, Oral / Q000008:administration & dosage; D014611:Vaccination
D011055:Poliovirus Vaccine, Oral