The high season for snakes is upon us. Readers have been hearing and asking about the Rattlesnake Vaccine. We asked Dr. Conn what she thinks of the vaccine, who should get it, how it works, and how effective it is. This is what she had to say.
This vaccine is meant for use in healthy dogs to help decrease the severity of rattlesnake bites. The vaccine is specifically for the toxin of Crotalus atrox which is the western diamondback rattlesnake and provides the best protection against the venom of that particular rattlesnake. The vaccine is produced from inactivated Crotalus atrox venom with an adjuvant and preservatives added. The vaccine has been shown to provide cross protection against the venom of other types of rattlesnakes and copperheads since the venom of pit vipers share some of the same toxic components. The vaccine however does not provide protection against the Mojave rattlesnake, cottonmouths or coral snakes. Benefits of the vaccines are that it allows more time to get to a veterinary hospital, it reduces the amount of pain and swelling experienced and provides faster recovery times.
The vaccine works by stimulating the dog’s immune system to produce antibodies against rattlesnake toxin. The antibodies are short lived and the vaccine typically only provides protection for six months necessitating a booster shot either once a year one month before “snake season” or twice a year in areas where rattlesnakes are year-round risks. To provide initial immunization, the dog will need two doses one month apart and must be at least four months of age.
It is important to keep in mind that no vaccine will ever provide 100 percent immunity. There are individual variations in the response to a vaccine, some dogs produce a lot of antibodies, some don’t. It does not provide equal protection against all rattlesnakes and in snake encounters it is often not known what kind of snake bit the dog; sometimes owners don’t even see the attacks. Protection from the vaccine will wane over time necessitating boosters. Sometimes so much venom is injected into the bite wound that it overwhelms the amount of antibodies.
Therefore, this vaccine should not be used solely as a means of protection against rattlesnake bites. It is meant to provide some protection and to reduce the severity of the snakebite. Your dog will still need emergency treatment and in some cases will still need antivenom. Like all vaccines, there is always a risk of an anaphylactic reaction which can be mild like a skin reaction, or in severe cases, can result in anaphylactic shock which can be fatal. Because it interferes with the body’s immune system there is concern in some veterinary circles that over-vaccination can cause immune meditated diseases such as IMHA which is when the immune system starts attacking the red blood cells.
I typically do not recommend this vaccine to my patients, except for specific situations. For example, if you plan on taking your dog hiking or camping in known rattlesnake areas where you may not have access to veterinary attention or if you live in a rattlesnake endemic area and your nearest vet clinic is far away. In those scenarios, the vaccine may be worth looking into.
Read more: What you need to know about snakes.
Read more: Rattlesnake Aversion Training
About Dr. Kristy Conn
Dr. Kristy Conn graduated from Ross University School of Veterinary Medicine and did her clinical year at the University of Minnesota Veterinary Teaching Hospital where she fell in love with emergency and critical care medicine. She has practiced emergency medicine at various clinics almost exclusively for the past 10 years, in addition to volunteering in shelter medicine, checking on the health of arrivals and providing low cost spay/neuters and immunizations to recently adopted animals. She is a member of the National Animal Health Emergency Response Corps which helps provide veterinary care to animals affected by disasters such as Hurricane Katrina. She resides in Long Island with her beloved mixed breed dog named Buster.