title: A comparison of subcutaneous, nasal, and combined influenza vaccination. II. Protection against natural challenge.
mesh_terms: D000041:Absenteeism; D000336:Aerosols; D000367:Age Factors; D000368:Aged; D000906:Antibodies / Q000032:analysis; D000917:Antibody Formation; D003168:Complement Fixation Tests; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D007252:Influenza Vaccines / Q000008:administration & dosage*; D007251:Influenza, Human / Q000175:diagnosis / Q000453:epidemiology / Q000276:immunology / Q000517:prevention & control*; D007279:Injections, Subcutaneous; D009500:Neutralization Tests; D009666:Nose; D011159:Population Surveillance; D014481:United States; D014611:Vaccination
chemical_list: D000336:Aerosols; D000906:Antibodies; D007252:Influenza Vaccines