The standard kitten core vaccine series begins at 6–8 weeks of age, with doses repeated every 2–4 weeks until 16 weeks of age or older, followed by a booster at 26 weeks (6 months) of age. Core vaccines are feline herpesvirus type 1 (FHV-1), feline calicivirus (FCV), feline panleukopenia virus (FPV), feline leukemia virus (FeLV) for kittens, and rabies.AAHA Clinical G…+1
The number of doses in the primary series depends on the age at which vaccination begins. A kitten starting at 6–7 weeks of age requires four primary core vaccine doses; one starting at 8–9 weeks requires three doses.WSAVA Global Gu… Intervals shorter than 2 weeks between doses interfere with successful immunization, particularly with attenuated live vaccines.AAHA Clinical G…
The 6-month (26-week) booster for FHV-1, FCV, and FPV is recommended to close the window of susceptibility created by maternally derived antibodies (MDA). Up to one-third of kittens may fail to respond to a final core vaccine at 16 weeks and may retain blocking MDA levels at 20 weeks.AAHA Clinical G… The 26-week booster ensures that any kitten that failed to seroconvert during the primary series is protected before 12 months of age, rather than remaining unprotected until a traditional 12-month booster.WSAVA Global Gu…+1 Adopting this protocol may require up to five vaccine visits in the first 6 months of life when vaccination begins at 6–7 weeks.WSAVA Global Gu…
FeLV vaccination is core for all kittens and young cats under 1 year of age due to age-related susceptibility. The initial series consists of two doses 3–4 weeks apart, beginning as early as 8 weeks of age.AAHA Clinical G… FeLV revaccination is administered 12 months after the last dose in the kitten series, then annually for cats with regular exposure to FeLV-positive cats or cats of unknown status, or every 2–3 years (where product licensure allows) for adult cats with lower exposure risk.AAHA Clinical G…+1 FeLV antigen status should be established by testing prior to vaccination.AAHA Clinical G…
After the 26-week core booster, the next core (FHV-1/FCV/FPV) revaccination is not required for at least 3 years in a low-risk cat. For adult and senior cats, revaccination intervals for FHV-1, FCV, and FPV depend on vaccine label, vaccine type, route of administration, and individual risk assessment.WSAVA Global Gu…+1 The risk-benefit of vaccinating senior cats should be weighed against their overall health status.AAHA Clinical G…
Regarding titers: the provided sources do not describe specific titer protocols or cutoffs for determining when serologic testing should replace vaccination in cats. The veterinary literature addresses this topic separately from the vaccination schedule guidelines cited here.
| Vaccine | Primary Series | 6-Month Booster | Adult Revaccination |
|---|---|---|---|
| FHV-1, FCV, FPV | Every 2–4 weeks from 6–8 wks until ≥16 wks | Recommended at 26 weeks | ≥3 years (low-risk); interval varies by riskWSAVA Global Gu…+1 |
| FeLV | 2 doses, 3–4 weeks apart, starting ≥8 weeks | Not specified at 6 months | 12 months post-series, then annually (high-risk) or q2–3 years (low-risk)AAHA Clinical G… |
| Rabies | Per label and local regulations | — | Per label and local regulationsAAHA Clinical G… |
Would you like to go over the specific protocol for vaccinating a kitten with unknown vaccination history that presents at 12 weeks of age?