Core puppy vaccination begins at 6–8 weeks of age and repeats every 2–4 weeks until 16 weeks of age or older. The total number of doses in the primary series is determined by the starting age and the chosen interval between vaccinations.WSAVA Global Gu…
When vaccination starts at 6 or 7 weeks with a 4-week interval, four primary core vaccines are administered. When vaccination starts at 8 or 9 weeks with a 4-week interval, three primary core vaccines are sufficient.WSAVA Global Gu… The final dose in the series must be given at 16 weeks of age or older — this cutoff was specifically increased from the previous recommendation of 14–16 weeks to ensure adequate coverage of puppies whose maternally derived antibodies (MDA) persist at high enough titers to block vaccine response until 12 weeks of age or beyond.WSAVA Global Gu…
MDA is the central variable governing vaccine response timing. MDA wanes to a level permitting active immunization in most puppies by 8–12 weeks of age, but some puppies retain protective MDA titers as late as 18 weeks of age.WSAVA Global Gu…+1 Measuring MDA titers before designing a vaccination schedule reduces the risk of vaccine failure in individual puppies.BMC Veterinary…
In shelter settings, the American Animal Hospital Association (AAHA) recommends a modified-live virus (MLV) DA2PP vaccine at or before entry for all puppies 4 weeks of age and older, with boosters every 2–3 weeks until 18–20 weeks of age.AAHA Clinical G… Leptospirosis vaccination should not begin until at least 12 weeks of age; when initiated, a quadrivalent leptospirosis vaccine is given with a booster 3 weeks later.AAHA Clinical G…
| Starting Age | Interval | Total Core Doses | Final Dose Age |
|---|---|---|---|
| 6–7 weeks | Every 4 weeks | 4 doses | ≥16 weeks WSAVA Global Gu… |
| 8–9 weeks | Every 4 weeks | 3 doses | ≥16 weeks WSAVA Global Gu… |
| Any age (shelter) | Every 2–3 weeks | Until 18–20 weeks | 18–20 weeks AAHA Clinical G… |
| ≥12 weeks (shelter) | 3 weeks apart | 2 doses (lepto) | Booster at 3 wks AAHA Clinical G… |
Would you like guidance on how to handle a puppy with unknown or incomplete prior vaccination history?