title: The immunity gap and vaccination against poliomyelitis.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D006579:Heterozygote; D006801:Humans; D007110:Immunity, Active; D007114:Immunization; D007223:Infant; D011051:Poliomyelitis / Q000453:epidemiology / Q000235:genetics / Q000276:immunology* / Q000517:prevention & control; D017955:Poliovirus / Q000472:pathogenicity; D012959:Socioeconomic Factors; D014774:Virulence