Your puppy receives the bulk of their vaccines during the first year of their life, protecting them from common diseases such as:

• Bordetella
• Distemper
• Rabies
• Hepatitis
• Flu
• Parvovirus

If your area is high in ticks, parasites, infected wildlife, or contaminated water, your puppy may also receive vaccines against leptospirosis and Lyme disease.

Around 12 to 16 weeks, your puppy also begins receiving a monthly preventative medication for heartworm, a parasite spread through mosquitoes.

Vaccines prevent illness from spreading in the community while providing your puppy with protection against more serious diseases. While some animals experience short-term side effects such as discomfort or lethargy, serious long-term effects are rare and can be discussed with your vet.

Maternally-Derived Antibodies (MDA)

When your puppy is first born, they live exclusively off their mother’s milk. Specifically, they eat colostrum, a special type of milk that mammals produce immediately after delivering a newborn. Colostrum is loaded with maternally-derived antibodies that pass the mother’s immunity down to the infant, along with a host of other good stuff.

The amount of MDA that each litter, or even each puppy in a litter, receives can highly vary, most likely due to the timing of that first, crucial feeding. Lack of sufficient colostrum during those early stages is heavily associated with neonatal mortality rate. Unfortunately, approximately 10 percent of live-born puppies die before three weeks.

A puppy with strong MDA may be incapable of responding to vaccines before 12 weeks. The antibodies are powerful enough to neutralize their effect until then. If you’ve ever heard of a puppy getting sick after being vaccinated against that specific illness, they most likely had strong MDA. However, protection wanes by 16 weeks in all puppies, which is why the current recommendation encourages pet owners to start vaccinating by 12 weeks.

A puppy with poor MDA is more vulnerable to disease from an earlier age and responds to vaccines earlier. Because it’s hard to discern which category a puppy falls into or how long they’re protected for, vets recommend vaccinating early—it does not harm puppies with strong MDA and only helps puppies with poor MDA.

Puppy Vaccine Schedule

Your vet should follow the guideline outlined by the World Small Veterinary Association (WSAVA):

• 6-8 Weeks: Distemper, parvovirus
• 10-12 Weeks: DHPP (distemper, hepatitis, parainfluenza, parvovirus)
• 16-18 Weeks: DHPP, rabies
• 12-16 Months: DHPP, rabies
• Every 1-2 Years: DHPP
• Every 1-3 Years: Rabies

These are considered core vaccines that all dogs must receive for both their own and their community’s benefit. These diseases can be fatal in a puppy and spread quickly among the canine population if left unchecked.

Non-core vaccines—Bordetella, leptospirosis, influenza, Lyme disease, Coronavirus—are administered throughout the first year, depending on your vet’s discretion and your area’s individual risk. Although your puppy can receive a canine Coronavirus vaccine, please note that this does not provide protection against SARS-CoV-2, the virus that causes the COVID-19 infection. If you’re uncertain about whether your puppy needs to receive non-core vaccines, discuss your concerns with your vet.

Essentially, your puppy receives the core vaccines starting at around 6 weeks and continues to receive boosters every 2 to 4 weeks until they’re 16 weeks old, then receives a booster shot around 12 months of age or 12 months after their last shot.

However, WSAVA cautions that the booster shot’s timing has more to do with convenience—dog owners who bring their puppy in for the first annual health check can receive the booster shot then. Should a puppy fail to respond to any of the earlier core vaccinations, they may be left unprotected until that booster. Therefore, current guidelines are being revised to recommend that your puppy get a booster at around 6 to 7 months.

Shelter Puppy Vaccine Schedule

Because puppies adopted through a shelter are exposed to a greater number of dogs with unknown health histories, WSAVA recommends a different, more aggressive vaccine schedule for them. If you adopt your puppy through a shelter, you should receive a complete vaccine history so that you can transition your puppy to your vet smoothly.

The general recommendation for shelter puppies is to start the first round of vaccines by 4 to 6 weeks of age and repeat every 2 weeks until the puppies reach 20 weeks of age.

Many puppies get the kennel cough vaccine while in shelters. The vaccine is given not to prevent outbreaks but to manage symptoms. So if your puppy has kennel cough despite getting a shot for it, don’t worry—it’s totally normal.