Vaccination at the portal of entry of infectious agents.

Administration, Intranasal Administration, Oral Adult Child Child, Preschool Hepatitis A/prevention & control Herpes Simplex/prevention & control Humans Infant Influenza, Human/prevention & control Meningitis, Meningococcal/prevention & control Mycoplasma Infections/prevention & control Polysaccharides, Bacterial/therapeutic use Respiratory Tract Infections/epidemiology,prevention & control United States Vaccination/methods Vaccines/administration & dosage Virus Diseases/prevention & control

Polysaccharides, Bacterial Vaccines