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Pharmaceuticals2026-05-14 · 8 min read

Dog Vaccine Schedule: Puppy Shots, Adult Boosters, and Lifestyle Vaccines Explained

A guideline-based dog vaccine schedule built on AAHA's 2022 canine vaccination guidelines.

Ran Chen
Ran Chen
Founder, VetMedGuide. Life-sciences operator and 10× global market-access lead.
Published

Every dog needs vaccines, but not every dog needs the same vaccines at the same intervals. The AAHA Canine Vaccination Guidelines (published 2022, updated 2024) organize canine vaccines into two groups: core vaccines recommended for all dogs, and non-core vaccines added based on lifestyle, geography, and exposure risk. This article walks through the complete dog vaccine schedule from puppyhood through senior years, explains which vaccines are non-negotiable and which depend on your dog's situation, and covers what happens when vaccines are overdue or history is unknown.

Quick answer

Every dog should receive core vaccines: distemper, adenovirus-2, parvovirus, parainfluenza (often combined as DHPP or DAPP), rabies, and leptospirosis. Puppies start the combination vaccine at 6–8 weeks, with boosters every 2–4 weeks until at least 16 weeks of age. Rabies is given once at 12–16 weeks. Adult dogs receive boosters at 1 year after the initial series, then every 3 years for distemper/adenovirus/parvovirus and annually for leptospirosis. Non-core vaccines — Bordetella, Lyme, canine influenza, and rattlesnake toxoid — are added when a dog's lifestyle or location justifies them.

What "core" and "non-core" actually mean

AAHA defines core vaccines as those recommended for all dogs regardless of lifestyle, unless there is a specific medical reason not to vaccinate. Core vaccines protect against diseases that are widespread, have high morbidity or mortality, or pose a public health risk.

Non-core vaccines are recommended for some dogs based on risk of exposure. Factors that change the calculation include geographic region, boarding or daycare attendance, travel, hiking in tick-endemic areas, and contact with other dogs or wildlife. The term "non-core" does not mean optional — AAHA's framework encourages veterinarians to ask, "What is core for this patient?" and treat lifestyle vaccines as required for dogs whose risk profile warrants them.

Core vaccines every dog needs

The following vaccines are recommended for all dogs by AAHA and UC Davis School of Veterinary Medicine:

Vaccine Protects against Initial puppy schedule Adult revaccination
DHPP/DAPP (combination) Distemper, adenovirus-2 (hepatitis), parvovirus, parainfluenza At least 3 doses between 6 and 16 weeks, 2–4 weeks apart 1-year booster, then every 3 years
Rabies Rabies virus (fatal, zoonotic) Single dose at 12–16 weeks (as required by law) 1-year booster, then per product label (1-year or 3-year) and state law
Leptospirosis (4-serovar) Leptospira bacteria (kidney/liver failure, zoonotic) 2 doses, 2–4 weeks apart, starting at 12 weeks Annually

AAHA's 2022 guidelines designate leptospirosis as a vaccine that most dogs should receive. UC Davis and AAHA both note that leptospirosis is increasingly diagnosed in urban and suburban environments — it is not limited to rural dogs. Rodents, standing water, and wildlife exposure put even backyard dogs at risk.

Puppy vaccine schedule: what happens when

Puppies receive antibodies from their mother's milk (maternal immunity) in the first weeks of life. These antibodies decline over time, but while present they can interfere with vaccine response. This is why puppies need a series of doses — each booster catches puppies whose maternal antibodies have declined since the last dose.

Age Vaccine Notes
6–8 weeks DHPP/DAPP (dose 1) Start as soon as maternal antibodies begin declining
10–12 weeks DHPP/DAPP (dose 2) 2–4 weeks after dose 1
12 weeks Leptospirosis (dose 1) AAHA recommends starting at 12 weeks; some product labels allow as early as 8 weeks
12–16 weeks Rabies (single dose) As required by state law; minimum age 12 weeks
14–16 weeks Leptospirosis (dose 2) 2–4 weeks after lepto dose 1
14–16 weeks DHPP/DAPP (dose 3, final puppy dose) Must be given at or after 16 weeks to ensure maternal antibodies have waned

A puppy is not fully protected until approximately 2 weeks after the final DHPP dose. AAHA recommends that the final dose in the puppy series be administered at or after 16 weeks of age to maximize the chance of immunization.

For high-risk puppies (shelters, endemic parvo areas), some veterinarians add an extra DHPP dose at 18–20 weeks.

Adult dog boosters

After the puppy series, the adult schedule maintains immunity:

At 1 year of age (or 12 months after the final puppy dose):

  • DHPP/DAPP booster (1-year booster)
  • Rabies booster (required by law regardless of product used)
  • Leptospirosis booster (annual)

After the 1-year boosters:

  • DHPP/DAPP: every 3 years, per AAHA guidelines
  • Rabies: per product label and state law (1-year or 3-year cycle)
  • Leptospirosis: annually (immunity wanes within 12 months)

Adult dogs with unknown vaccination history should receive 2 doses of the combination vaccine 2–4 weeks apart, a single dose of rabies (followed by booster at 1 year), and 2 doses of leptospirosis 2–4 weeks apart. AAHA's position is clear: when vaccine history is unknown or overdue, the benefits of vaccinating outweigh the risks in nearly all cases.

Non-core (lifestyle) vaccines

These vaccines are added based on your dog's environment and activities.

Bordetella (kennel cough)

Bordetella bronchiseptica is a bacterial contributor to canine infectious respiratory disease complex (CIRD, often called kennel cough). It spreads through respiratory droplets wherever dogs congregate.

  • When it fits: Dogs who board, attend daycare, visit groomers, go to dog parks, or are housed in shelters.
  • Schedule: Single initial dose (intranasal or oral) or 2 doses (injectable, 2–4 weeks apart). Revaccination annually, or every 6 months for dogs in high-density environments.
  • Route: Available as intranasal, oral, or subcutaneous injectable.

Lyme disease (Borrelia burgdorferi)

Lyme disease is transmitted by infected black-legged ticks (Ixodes scapularis). It is most prevalent in the Northeast, mid-Atlantic, and upper Midwest, though the tick range is expanding.

  • When it fits: Dogs who live in or travel to Lyme-endemic regions, hike in wooded or tall-grass areas, or have tick exposure. AAHA recommends vaccination accompanied by monthly tick prevention.
  • Schedule: 2 doses, 2–4 weeks apart. Annual booster. The series should be completed 2–4 weeks before travel to endemic areas.
  • Note: Vaccination does not replace tick prevention. Both are recommended together.

Canine influenza (H3N2 and H3N8)

Canine influenza virus (CIV) causes acute respiratory illness. H3N2 is the more commonly circulating strain in recent years. Outbreaks are reported in shelters, boarding facilities, and veterinary clinics.

  • When it fits: Dogs who board, attend daycare, visit groomers, or are in regions with active outbreaks.
  • Schedule: 2 doses, 2–4 weeks apart. Annual booster.
  • Note: H3N2 and H3N8 are different strains — some vaccines are bivalent (cover both). Discuss with your veterinarian which product is appropriate.

Rattlesnake toxoid

A toxoid vaccine targeting the Western diamondback rattlesnake.

  • When it fits: Dogs in rattlesnake-endemic areas of the southwestern United States, particularly hunting dogs or dogs that hike in desert terrain.
  • Schedule: 2 initial doses, 2–4 weeks apart. Annual booster, or more frequently for dogs in high-exposure environments.
  • Limitation: The vaccine is designed to reduce severity of envenomation, not prevent it. Any snakebite still requires immediate veterinary emergency care.

Senior dogs and vaccine adjustments

Senior dogs should continue receiving core vaccines on schedule. There is no AAHA recommendation to stop core vaccination based on age alone. However, the conversation with your veterinarian may shift toward:

  • Whether non-core vaccines are still necessary if lifestyle has changed (e.g., a dog that no longer boards may not need Bordetella).
  • Whether titer testing is appropriate if the dog has a history of vaccine reactions (titers are available for distemper, parvovirus, and adenovirus but not accepted for rabies compliance).
  • Monitoring for age-related conditions that may affect vaccine response.

What to ask your veterinarian

Vaccine decisions depend on your individual dog. When you discuss the schedule, ask:

  • Which non-core vaccines are recommended for my dog's lifestyle? Boarding, hiking, travel, and regional disease prevalence all change the answer.
  • Is leptospirosis common in our area? Many practices now treat lepto as core for all dogs because of increasing urban prevalence.
  • What product and schedule do you use for DHPP? Some practices use 3-year labeled products after the 1-year booster; others administer annually. Both approaches are supported when following manufacturer labeling.
  • What are the rabies requirements in our state or county? Local law may be stricter than the product label.
  • How do you handle a dog with a history of vaccine reactions? Options include pre-treatment with antihistamines, spacing vaccines, or titer monitoring.

What this schedule does not do

This article provides a framework based on AAHA guidelines. It does not replace a vaccination plan designed by your veterinarian for your individual dog. Factors including breed, health status, reproductive status, prior reactions, and regional disease patterns all affect the right schedule. Dose amounts and specific product selection are veterinary decisions.

Sources

Topics
Vaccination & Infectious Disease
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