title: The protective effect of childhood infections.
authors.forename: S L
authors.initials: SL
authors.lastname: Johnston
authors.forename: P J
authors.initials: PJ
authors.lastname: Openshaw
mesh_terms: D001249:Asthma / Q000276:immunology*; D001424:Bacterial Infections / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D014777:Virus Diseases / Q000276:immunology*