Careena Chase almost stepped on this rattlesnake while watering her garden late afternoon Thursday, July 24. “I had turned around and was backing up trying to get my hose loose — thank God the hose stayed stuck,” Chase wrote in an email. The snake was 2 feet away from her. “He did not rattle until he moved up against the house and then rattled for only a moment.” Photo by Careena Chase
Careena Chase almost stepped on this rattlesnake while watering her garden late afternoon Thursday, July 24. “I had turned around and was backing up trying to get my hose loose — thank God the hose stayed stuck,” Chase wrote in an email. The snake was 2 feet away from her. “He did not rattle until he moved up against the house and then rattled for only a moment.”
Photo by Careena Chase

For people concerned about their dogs succumbing to rattlesnake bites, a preventive measure may be Crotalus Atrox Toxoid, a rattlesnake vaccine for canines that Red Rock Biologics in Sacramento developed.

The vaccine “was developed to provide protection for dogs against Western Diamondback Rattlesnake venom,” Red Rock’s website reads. “… this vaccine may also provide protection against the venoms of the Western Rattlesnake (including the Prairie, Great Basin, Northern and Southern Pacific varieties), Sidewinder, Timber Rattlesnake, Massasauga and the Copperhead. Partial protection may be obtained against Eastern Diamondback Rattlesnake venom. This vaccine does not provide protection against venom from the Water Moccasin (Cottonmouth), Mojave Rattlesnake or Coral Snake.”

The company claims that in dogs the vaccine generates antibodies that neutralize the venom. And while the vaccine doesn’t prevent a reaction to the venom, canines “experience less pain and have a reduced risk of permanent injury from rattlesnake bite,” according to Red Rock. “Veterinarians typically report that vaccinated dogs bitten by rattlesnakes experience less swelling, less tissue damage and a faster recovery from snakebite than unvaccinated dogs.”

Janice Murasko of Animal Rescue Friends of Idyllwild said, “We give the vaccine at Sadie’s Clinic, and we have had at least two people say their dogs were hit by a rattler, and the only reason they survived was because of it. It gave them the time to get to the vet off the Hill.

“The first year, the dog gets two injections a month apart,” she said. “After that it is once a year.” A shot costs $25 and the supply is unlimited, she said. To make an appointment, call 951-659-1122 and leave a message on number 2.

But the vaccine is controversial. Local resident Kathy Keane’s dog, Lucky, died despite having a vaccination within six months of his death from what she believed was a Southern Pacific rattlesnake along a trail in Idyllwild. He was due to receive the vaccine in June when he was bitten May 30 of this year.

Still, Keane recommends vaccinating but warned, “It’s important to know that the vaccine only protects against venom B, the typical rattlesnake venom, a hemotoxin that causes localized swelling and tissue damage (and later possible neurological damage if treatment is delayed).”

She agrees with Murasko that it gives a person more time to get to the vet for anti-venom administration, if necessary. “The vaccines do not protect at all against venom A, the neurotoxic venom,” said Keane. “Our Southern Pacific rattlesnake has both types of venom.”

The University of California, Davis, Veterinary Medical Teaching Hospital goes even further and discourages the vaccine with its canine vaccination guidelines: “The product license is currently conditional as efficacy and potency have not been fully demonstrated. Based on existing evidence, the UC Davis VMTH does not currently recommend routine vaccination of dogs for rattlesnake envenomation, and the vaccine is not stocked by our pharmacy.”

Pets Vet Office Manager Jordan Schrader in Hemet said Dr. Robert Rizon in that office recommends the vaccine, however. “We’ve had a big success rate in dogs bitten by rattlesnakes,” Schrader said. “The share of survivors is greater. It’s not a cure, however, but most dogs survive because it gives the owner time to get to a vet who offers the anti-venom as we do.”

Unfortunately, Lucky did not make it when he was taken to Pets Vet. “We think it was a different type of [venom] strain,” Schrader said.

Schrader said Pets Vet vaccines also are $25 and the vet recommends a booster shot three weeks later, then an annual shot.

Dr. Lindsay Crowley, a mobile vet in Anza, also carries anti-venom for horses, said Murasko. Her phone number is 951-444-1838.

No vaccine has been developed for humans.