Fever After Simultaneous Versus Sequential Vaccination in Young Children

Inclusion Criteria: 1. 12 through 16 months of age (i.e. from the 1-year birthday until the day before 17 months of age) at the time of vaccination 2. Stable health as determined by investigator's clinical examination and assessment of child's medical history 3. Has received all immunizations recommended by Advisory Committee for Immunization Practices (ACIP) during the first year of life with the exception of rotavirus and influenza vaccines. 4. The parent(s)/ legally authorized representative(s) LAR(s) intend for the child to receive DTaP and PCV13 in addition to this season's IIV 5. The parent(s)/LAR(s) must be willing and capable of providing permission for their child to participate through the written informed consent process 6. The parent(s)/LAR(s) must be able to comply with the requirements of the protocol (e.g., completion of the memory aid (either electronic or paper diary), return for follow-up visits, respects intervals between the visits and have telephone access. 7. The parent(s)/LAR(s) must be English speaking 8. The parent(s)/LAR(s) must agree to sign a medical release for the child so that study personnel may obtain medical information about the child's health (if needed) Exclusion Criteria: 1. History of any seizure (including febrile seizure) in the child or a febrile seizure in a first degree relative 2. Has already completed influenza vaccination during the current season per ACIP recommendations 3. Receipt of more than 3 previous doses of DTaP 4. Received the 3rd dose of DTaP within 6 months of Visit 1 5. Receipt of more than 3 previous doses of PCV13 6. Received the 3rd dose of PCV13 within 8 weeks of Visit 1 7. History of a severe allergic reaction (e.g. anaphylaxis) to a previous dose of any influenza, diphtheria toxoid-, tetanus toxoid-, or pertussis-containing vaccine, or pneumococcal vaccine. 8. History of a severe allergic reaction (e.g., anaphylaxis) to any component (including egg protein) of any of the three vaccines used in this study; or a latex allergy. 9. History of Guillain-Barré syndrome within 6 weeks following a prior dose of influenza, DTaP, or tetanus toxoid containing vaccine 10. History of a progressive neurologic disorder 11. History of encephalopathy within 7 days of a previous pertussis-containing vaccine 12. History of collapse within 3 days after a prior dose of DTaP 13. Received any other licensed vaccines within 14 days (for inactivated vaccines) or 28 days (for live vaccines) prior to Visit 1 14. Received an experimental/investigational agent (vaccine, drug, biologic, device, blood product, or medication) within 28 days prior to Visit 1, or expects to receive an experimental/investigational agent during the study period (up to 8 days after visit 2) 15. A moderate to severe acute illness within 72 hours of Visit 1 16. A reported temperature greater than or equal to 100.4°F (38.0°C) within 72 hours prior enrollment or a temperature (measured by temporal artery thermometer) greater than or equal to 100.4°F (38.0°C) at the time of enrollment 17. Receipt of an antipyretic medication (acetaminophen or ibuprofen) within 24 hours prior to enrollment 18. Parent(s)/LAR is planning to administer a prophylactic antipyretic or medication on the day of, and/or within 7 days following Visit 1 or Visit 2 19. Long term (at least 14 consecutive days) oral corticosteroids (prednisone 2 mg/kg/day or equivalent other glucocorticoid), any parenteral steroids, high-dose inhaled steroids (\>800 mcg/day of beclomethasone dipropionate or equivalent) or other immune-modifying drugs or immunosuppressants within the preceding 6 months prior to Visit 1 20. Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and or their provider's routine physical examination 21. Has an active neoplastic disease, a history of any hematologic malignancy, current bleeding disorder, or taking anticoagulants. 22. Unable to receive an intramuscular injection in the thigh 23. Any condition deemed by the investigator to place the child at increased risk as a result of their participation in the study 24. Any child or grandchild of a study investigator or study team member