title: Infections preventing atopy: facts and new questions.
authors.forename: P M
authors.initials: PM
authors.lastname: Matricardi
mesh_terms: D003140:Communicable Disease Control; D003141:Communicable Diseases / Q000276:immunology*; D006801:Humans; D006920:Hygiene; D006969:Hypersensitivity, Immediate / Q000453:epidemiology / Q000276:immunology / Q000517:prevention & control*; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology