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All communities will be placed in read-only mode (you will be able to see and search for posts but not start or reply to discussions) as we conduct maintenance. We will make another announcement when posting is re-opened. Thank you for your continued support and patience, and if you have any further questions, please email

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ricardo5252 posted:
Can a dog who is vaccinated yearly (6) for parvo virus still catch disease
srstephanie responded:
Hi ricardo5252,

I'm not a vet ... but I'm a good friend of Dr Richard Ford (emeritus, NC State) who is one of the co-authors of the AAHA Canine Vaccination Guidelines. He is renown and respected as an expert in vaccinology ... and is also known as an infectious disease expert.

I've heard multiple vet CE talks by Dr Ford and others ... and have spoken often with Dr Ford. All would answer your question with a YES!

The vaccine for Parvovirus (any company ... all are modified live virus vaccines) is VERY good ... and in the vast majority of dogs, once vaccinated as an adult ... it is considered protective for at least 7 years and most feel that the majority of dogs are protected for life. The current 2011 AAHA Vaccination Guidelines recommend booster vaccinations (after the initial 1-yr booster) be given every "3 or more years" ... just in case some dogs may not respond well.

BUT long-term immunity is assuming that they responded to the vaccine. There have always been a minority of dogs that are known as "non-responders" ... who simply will not respond immunologically to a vaccine, no matter how many times it is given. Vaccines are not "drugs" ... they are "biological products" ... hence are not licensed by the FDA, but by the US Department of Agriculture, Center for Veterinary Biologics (USDA-CVB). The point being, that an individual dog's genetics can determine how it responds to the injection of a biological product. It is unknown why some dogs simply do not respond to a particular vaccine antigen. The dog may have an immunological response to other antigens (e.g. Adnovirus, Distemper, etc) but just not to one antigen (e.g. parvovirus).

If one wants to know if their dog responded to a parvovirus vaccine, a titer test can be done about 2 or more weeks post vaccination to look for an antibody response. Antibodies do not indicate protection for all diseases ... BUT they are a good indication of protective immunity for parvovirus (or panleukopenia in cats, which is a parvovirus).

One final note ... there are several strains and variants of parvovirus. There has been some concern among veterinarians about the newer Parvovirus 2c variant... BUT tests have shown that all of the current parvovirus vaccines will protect for parvovirus 2a, 2b AND 2c.

Bottom line ... parvovirus vaccines are very good vaccines, BUT no vaccine protects 100% of all dogs ... and some dogs are simply, biologically, "non-responders".

Hope that helps.
Stephanie in Raleigh
healingpaws replied to srstephanie's response:
srstephanie , is there any way I could send you a personal e-mail? I have a pretty general question in regards to feline vaccinations and I would love to hear your insight and thoughts!
srstephanie replied to healingpaws's response:

I check webmd irregularly and just now saw your post. Sure you can write to me. Use this address which forwards it to my private email account. If I get too much spam on it, I can easily change it:


William Draper, DVM, better known as "Dr. Will," is a well-known small animal practitioner in the Atlanta, GA area. He grew up in Inglewood,...More

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