Most people living in Santa Barbara are aware that we share our slice of paradise with numerous slithery friends.
Most snakes are non-venomous and will cause no harm to humans or animals. Like most wildlife, they are more afraid of you than you are of them.
The only venomous snakes in California are in the rattlesnake family. There are eight species: the Southern Pacific rattlesnake, the Northern Pacific rattlesnake, the Great Basin rattlesnake, the western diamondback, the red diamondback, the sidewinder, the speckled rattlesnake, and the Mojave green rattlesnake.
In Santa Barbara, our two local rattlesnake species are the Northern Pacific and Southern Pacific.
Rattlesnakes live in both rural and suburban locations. They are active all year round, but are most active (and therefore most likely to bite) between the warmer months of April and October.
Close Encounters
Dogs are most likely to encounter rattlesnakes when hiking, camping, or if they live in more rural areas with more access to wildlife. This could even happen in your own backyard.
Remember that snake bites are a defensive behavior. If they perceive you, your children, or your pets as a threat, they will attack and bite.
They are not, by nature, aggressive. The most common location for a dog or cat to be bitten is on the face, neck, or extremities.
Most rattlesnake venom causes hemotoxity and blood-clotting disorders, which lead to disruption of the integrity of the blood vessels and uncontrolled bleeding.
The bite location will swell dramatically, with up to to a third of the total blood circulation diffusing into tissues. Tissue death can develop within hours to days, and can be severe, requiring long term wound management.
The combination of toxicities can lead to rapid and severe blood loss, shock, and potentially death.
The venom of the Mojave rattlesnake is different. It is generally neurotoxic, leading to rapid paralysis of the respiratory muscles and suffocation.
Because of this, treatment may vary, and the snake venom vaccine (see below) is not protective against this venom. Interestingly, some Mojave rattlers have now been identified as having both neurotoxic and hemotoxic effects, suggesting hybridization.
Not All Bites Are Created Equal
It is impossible to know, at the time of a bite, how severe the symptoms will be.
The severity is determined by the type of snake, the size of the pet (the smaller the pet, the more severe the symptoms), the location of the bite (symptoms generally worse for bites on head, neck, and chest), and how much venom was released at the time of the bite.
The amount of venom released at the time of the bite can vary widely. Contrary to popular belief, the larger (and older) the snake, the more venom that can/will be released into the bite. A snake that perceives a greater threat may also deliver more venom into its bite.
Snakes that have been “grasped” may release more venom for this reason, according to some studies.
Snakes of any age can control the amount of venom they release during a bite.
Approximately 20-25% of bites are dry, meaning no venom has been injected. Thirty percent of bites are mild, causing local pain and swelling in the bite area but no systemic symptoms.
Forty percent of bites are severe, requiring intensive intervention and longer hospital stays (and vet bills to match). Only around 5% of bites are fatal.
Treatment — Sooner the Better
The faster the bite is recognized, and treatment instituted, the more effective the treatment is. Antivenin is the definitive treatment for snake bite envenomation.
Do not try to suck out the venom, cut the wound open, ice the wound, or apply bandages or pressure to the bite. Remove any collars, if present, since swelling can be rapid.
The most important thing you can do is to seek immediate veterinary care at the nearest emergency hospital with in-stock antivenin. Your pet will be hospitalized, with IV fluids instituted, along with other supportive treatments for wound care, pain management, and maintenance of fluid volume and blood clotting.
Our nearest veterinary emergency hospitals that provide 24-hour emergency care and stock antivenin are:
- Advanced Veterinary Specialists, 414 E. Carrillo St., Santa Barbara, CA 93101; 805.729.4460.
- VCA Care Specialty and Emergency Animal Hospital, 301 E. Haley St., Santa Barbara 93101; 805.618.2440.
- PETS Hospital, 4854 S. Bradley Road, Suite 109, Orcutt, CA 93455; 805.250.5600.
What Is Antivenin?
Antivenin is a medical biological product consisting of antibodies created from horses that have been immunized to the venom. Antivenin binds and neutralized venom toxins.
It is extremely important in the treatment of snake envenomation, but is most effective when given within four hours of the bite.
It is very expensive, and several vials may be needed in the course of treatment. There is a small risk of allergic reaction to the antivenin due to the equine origin.
Vaccination Can Help
Dogs that live an at-risk lifestyle (hiking, camping, residing in areas where rattlesnakes are known to live) are all good candidates for the rattlesnake vaccine.
This vaccine (made by Red Rock Biologics) is stated to be effective against the venom of the western diamondback.
It purportedly has activity against the venom of six out of seven other California rattlesnakes (though not the Mojave), and there may also be cross-protection against numerous other venomous snakes outside California.
There is some controversy about how effective the vaccine is, as the manufacturer has not performed efficacy testing, as this would involve exposing unvaccinated dogs to venom.
More peer-reviewed studies are warranted, although anecdotal evidence suggests that the vaccine may be equivalent to one to two vials of antivenin.
The vaccine is given as a series of two doses 3-4 weeks apart, with some adjustments made based on body size. Boosters are then given annually, ideally in the spring before “snake season.”
Boosters can be given twice yearly for very high-risk dogs living in the foothills or other rural areas.
It is important to note that the goal of the vaccine is to lessen the severity of the symptoms; it does not preclude emergency treatment. Even a vaccinated dog must be taken to an emergency veterinary hospital for treatment immediately.
Snake Avoidance Training
Dogs can be trained to avoid rattlesnakes. This is done at yearly clinics, usually offered in the spring. A few are offered in our area — check your local boarding facilities and trainers for more information.
Teaching a dog snake avoidance is probably the most effective way to avoid envenomation side effects, better even than vaccination.
As with so many other scenarios, an ounce of protection is worth a pound of cure. Remember that we live in the natural habitat of these venomous snakes.
Most bites are defensive, so if you can spot a snake, back off and let the snake move away on its own. Protect yourself by being aware of your surroundings, and consider hiking in thick clothing and sturdy footwear.
Stay on open trails and avoid walking in tall brush where you won’t see a snake (bonus, you’ll avoid ticks this way also).
Stay alert for the warning sounds of a snake, as you may hear them before you see them. Sign your dog up for rattlesnake avoidance clinics, even yearly if needed.
Consider vaccinating your dog if they are at risk in their daily activities or before traveling to rattlesnake-heavy trails.
If your pet (dog or cat) is bitten, get them to the nearest veterinary emergency hospital for immediate care.
With prompt attention, the prognosis for your pet is good.
For your pocketbook, that might be another story! Pet insurance is always a great idea.