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Are Multiple Parvo Shots Really Necessary?

Why Do Puppies Need Multiple Parvo Shots?Whether you’ve had a dog before or not, you probably already know that welcoming a new puppy into your life almost always requires a couple of vet trips. While the usual routine checkup is a must, your vet will also talk to you about the Parvo vaccine. They will more than likely put your puppy on a vaccination schedule once they turn eight weeks old. That means that throughout the year, you will need to bring your puppy in for a Parvo shot every three to four weeks until they reach the age of 16 weeks. A final dose is required one year after that, making it a total of three vaccinations. 

To most pet parents, three Parvo shots may seem a bit concerning—excessive, even—which is completely understandable. Isn’t one vaccination enough? Does every Parvo shot increase a puppy’s immunity to the disease? Why is there a need to get puppies revaccinated every three to four weeks? Well, as unnecessary as multiple Parvo shots may seem, there is actually a good reason behind it. On top of having underdeveloped immune systems, puppies are born with maternal antibodies, which can interfere with the vaccination.

What Are Maternal Antibodies?

Why Do Puppies Need Multiple Parvo Shots?Maternal antibodies are disease and infection-fighting proteins transferred from a mother dog to her puppies. They are meant to provide temporary protection while a puppy’s immune system undergoes a vulnerable development period. During this time, the puppies gain their mom’s immunity, meaning that they will be immune to the same pathogens their mother is immune to. As puppies get older, this passive immunity will gradually fade away. Without timely vaccinations, they are left unprotected from harmful microorganisms, like Parvo.


When Do Puppies Lose Their Maternal Antibodies?

Why Do Puppies Need Multiple Parvo Shots?Maternal antibodies normally begin wearing off when puppies are six to eight weeks old. This is why veterinarians recommend that puppies receive their first round of Parvo shots, as well as other vaccines, around that time. However, every puppy is unique and may lose its maternal antibodies for different pathogens at different times. Some could stay protected from Rabies for up to three months but lose immunity to Parvo within three weeks. Puppies’ immune systems learn how to fight various types of foreign bodies. It also prevents diseases and infections from the get-go through the different vaccination series.


So, How Do Multiple Parvo Shots Protect Puppies?

Why Do Puppies Need Multiple Parvo Shots?Unfortunately, there’s no way of knowing whether or not a puppy still has their maternal antibodies. Veterinarians have simply observed that most puppies respond well to vaccinations once they reach six to eight weeks of age. However, when it comes to vaccines, guessing isn’t an option. There have been cases where puppies still have their maternal antibodies up until they are eight weeks old. 

Failed vaccinations in puppies are most common when there is a presence of maternal antibodies. This is because that passive immunity can inactivate vaccines before they get the chance to trigger a response from the puppy’s immune system, preventing them from gaining immunity. In the case of Parvo, puppies receive multiple Parvo shots between the age of eight to sixteen weeks to make sure that they’re always protected. According to PetMD, puppies are likely to have no maternal antibodies left once they turn 14 to 16 weeks old, which is why the last Parvo shot is given around this time. 

Ultimately, puppies can lose their maternal antibodies at any given moment. Some may become susceptible to diseases and infections at eight weeks old, others at ten weeks, and so on. To be sure that puppies are protected, they need to receive Parvo shots every three weeks starting at six to eight weeks of age up until they reach sixteen weeks of age.

Has your puppy completed their Parvo shot series?