Plain-English answers to the vaccine questions people actually ask
The CDC pages are authoritative but dense. These guides translate the schedule into practical answers for the situations that come up most often: new nursing students, healthcare hires, first-year college students, and adults who lost their vaccine records.
By audience
K–12 school vaccine questions parents ask
Missing records, in-process enrollment, exemptions, natural chickenpox immunity, and what to do when the school nurse says no.
Child & adolescent vaccine schedule (7–18)
The 11–12 and 16-year visits, HPV 2-vs-3 doses, catch-up rules, and how state school requirements differ.
College vaccine questions students ask
Meningococcal (MenACWY vs MenB), dorm rules, Hep B for non-clinical majors, and exemptions.
College vaccine requirements, explained
What most U.S. colleges require: MMR, meningococcal (MenACWY), Hep B, and the dorm rule.
Healthcare worker titer & vaccine questions
Negative varicella titers, lost Hep B titers, equivocal results, and when to start onboarding titers.
Healthcare worker vaccine requirements
The standard hospital and clinical-program checklist: titers, Tdap, Hep B, flu.
USCIS immigration vaccine questions
Current 2026 I-693 list, the May 2024 polio addition, COVID-19 removal, foreign records, and titer limits (including polio).
USCIS immigration vaccine requirements
The Form I-693 vaccine list, including the polio (IPV) rule that changed in May 2024.
Understanding titers
Titer questions — the confusing parts explained
Quantitative vs qualitative, equivocal results, negative titers after vaccination, and which titers actually work.
How long to wait after a vaccine before a titer
Exact intervals per vaccine — Hep B (1–2 months), MMR/varicella (≥4 weeks), and why draws too soon fail.
Should I get a titer or a booster?
When it's cheaper and faster to test than to re-vaccinate — and when it isn't.
Do I need an MMR booster as an adult?
The one-dose vs two-dose question, born-in-1957 rule, and when a titer replaces a booster.