Flu · Optional
Influenza (Flu) (Flu)
Flu is given from 6 months of age and is optional in this planner (CDC and AAP recommendations differ). The Influenza (Flu) vaccine protects against Seasonal influenza.
Not a standard school requirement
Key takeaways
- On the routine, on-time schedule, Flu is a 1-dose series. Delaying the start doesn't change the total number of Flu doses — it spaces them out.
- Flu can be given on a slower, spaced-out schedule. The dose count stays the same, but visits can be spread out. Minimum ages and intervals still apply, and the planner enforces them automatically.
- None of the Flu products listed on this page contain an aluminum adjuvant.
- Flu is generally not required for kindergarten entry. Check your state's specific rules.
What changes when Flu is delayed?
On the routine, started-on-time schedule, Flu is a 1-dose series. Delaying the start does not always change this, but for several vaccines the CDC's own catch-up rules mean a later start needs fewer total doses. Here is what applies to Flu:
- Given every year in the fall/winter, starting at age 6 months.
- First-ever flu season for a child under 9: 2 doses ≥4 weeks apart; otherwise 1 dose/year.
- Flu vaccine is yearly, so this plan shows only the FIRST season (never-vaccinated child): 2 doses ≥4 weeks apart under age 9, 1 dose from age 9. Repeat 1 dose each fall after that; a child who already had 2 earlier doses needs only 1. Plan with your child's healthcare practitioner each fall.
The exact timing depends on your child's age and how you space visits. The spaced-out scheduler applies these rules automatically and shows the minimum doses still needed by your deadline. For a fuller look at timing, risks and catch-up, see the delay guide for Flu.
What brands and ingredients does the Flu vaccine have?
The US-licensed products below are listed with their manufacturer, aluminum content, preservative and egg flags, and full ingredient list. Each card links to the official CDC or FDA source. Formulations change — treat these as a starting point, not the final word.
Single-disease brands
Fluzone (Trivalent)
Sanofi
Inactivated, egg-based, age 6mo+. Single-dose presentations are thimerosal-free; multi-dose vials contain thimerosal.
Ingredients (5)
- egg protein
- formaldehyde
- octylphenol ethoxylate (Triton X-100)
- sodium phosphate-buffered sodium chloride
- thimerosal (multi-dose vials only)
Flucelvax (Trivalent)
Seqirus
Cell-based (egg-free), inactivated, age 6mo+.
Ingredients (5)
- Madin Darby Canine Kidney (MDCK) cell protein & DNA
- phosphate-buffered saline
- polysorbate 80
- cetyltrimethylammonium bromide (CTAB)
- beta-propiolactone
FluMist (Trivalent)
AstraZeneca
Live attenuated, intranasal, ages 2–49 years.
Ingredients (8)
- monosodium glutamate
- hydrolyzed porcine gelatin
- arginine
- sucrose
- potassium phosphate
- ovalbumin
- gentamicin sulfate
- EDTA
Flu vaccine FAQs
How many doses of Flu does my child need?
On the routine, on-time schedule, Flu is a 1-dose series. Delaying the start doesn't change the total number of Flu doses — it spaces them out.
Can the Flu vaccine be delayed or spaced out?
Yes. Flu can be given on a slower, spaced-out schedule. The dose count stays the same, but visits can be spread out. Minimum ages and intervals still apply, and the planner enforces them automatically.
Does the Flu vaccine contain aluminum?
No. None of the Flu products listed on this page contain an aluminum adjuvant.
Is Flu required for school?
Flu is generally not required for kindergarten entry. Check your state's specific rules. See requirements by state.
Plan Flu on a slower schedule
See how many Flu doses your child would still need and when, on a spaced-out plan that finishes in time for school. Review the result with your child's healthcare practitioner.
Build my plan →Sources
Primary sources only. Links open the publisher's own page.
- CDC Child and Adolescent Immunization Schedule by Age (opens in a new tab)
- CDC Catch-up Immunization Schedule (Table 2) (opens in a new tab)
- CDC Child and Adolescent Schedule Notes (opens in a new tab)
- CDC Vaccine Excipient Summary (Pink Book, Appendix B) (opens in a new tab)
- FDA Vaccines Licensed for Use in the United States (opens in a new tab)
- CDC CDC Vaccine Excipient Summary (Appendix B) (opens in a new tab)
- DailyMed FDA/DailyMed PI — Fluzone (opens in a new tab)
- DailyMed FDA/DailyMed PI — Flucelvax (opens in a new tab)
- DailyMed FDA/DailyMed PI — FluMist (opens in a new tab)