One of the most common presentations at our emergency clinic during the spring and summer months are unhappy patients with extremely swollen faces and limbs. Often these are caused by an altercation with one of the various poisonous critters in our area. Snake bites seem to be the most common of the three. Dogs and cats are very curious about these strange animals. My own dog, Kody, would play with any snake he found, and he never learned that they are best left alone.
There are three main types of snakes in central Virginia. They are the pit vipers i.e. copperheads, water moccasins, and rattlesnakes or coral snakes. I have encountered all three types of vipers, both on the family farm and during my many hikes in our area. The second kind of snakes are coral snakes. I have not seen one in our area. They are extremely shy and nocturnal, but they are reported to exist in our area. You can tell a coral snake from the like colored kingsnake by the old adage, red/yellow dangerous fellow, red/black safe for Jack.
Pit vipers are by far the most common cause of snakebites in Virginia. Copperheads are the most common bite in our area. Pit viper venom causes marked swelling initially. The venom causes destruction of vascular walls, a drop in blood pressure, prevent normal clotting, and can cause respiratory and cardiovascular failure in severe cases. Most owners notice the swelling that is intensely painful initially. As a side note, newly hatched snakes tend to have a worse bit than larger ones. They cannot control how much venom they inject whereas a more mature viper has more control. Rattlesnake bites tend to be more severe than copperhead or water moccasin bites. Treatment consists of antivenin, antibiotics, pain control, and supportive care. The earlier the antivenin is administered the more effective it will be. The antivenin itself carries the risk of an allergic reaction to it. The patient must be monitored closely after it has been administered. Patients usually require supportive care for 24 to 48 hours.
Coral snake venom is extremely potent. The bite itself is much harder to recognize. Coral snakes have very small fangs located near the rear of their oral cavity. When they bite, it is not a strike like a pit viper. They latch on and chew on their victim to release their venom. The bite site itself is very hard to see, especially in our long coated furry friends. Even worse, clinical signs can be delayed for up to 12 hours, making it hard to identify that your pet is headed for a problem. Once present, clinical signs progress rapidly. In addition to the swelling that you normally see with a snakebite, coral snake venom causes neurologic signs and rapid respiratory failure. The venom paralyzes muscles including the ones responsible for breathing. Treatment consists of antivenin specific for coral snakes, aggressive supportive care, and careful monitoring.
There are two venomous spiders found in Virginia. They are the Black Widow Spider and Brown Recluse. The Black Widow is much more common in our area. They, as the name implies, are black, but have a red hourglass marking on their stomach. The bite itself is often very hard to see on our pets. Common clinical signs of a Black Widow bite include loss of sensation to the affected area, twitching, and difficulty breathing. These can then progress to swelling, seizures, and paralysis. Treatment consists of muscle relaxants, supportive care, and antivenin.
Brown Recluse bites are rarely seen in our area, but they do occur. Unlike the Black Widow, the Recluse releases venom that is extremely toxic to tissues. The bites are recognized by the severe necrosis they cause. The bitten area is often quite painful. The bite itself is not often seen, but has a bull’s eye appearance when noted. There is no antidote for a Brown Recluse bite. Treatment consists of supportive care, antibiotics, and pain control. With both types of spiders, proper identification is important. If safely possible, carefully collect the culprit and bring it with you to your veterinarian. Don’t get bitten yourself!!
The last type of bite that I want to cover is bee stings. Bee stings include hornets, yellow jackets, regular bees, and wasps in our area. Bee stings contain various toxic components. They cause marked inflammation, pain, and can cause an anaphylactic reaction just as in people. Common clinical signs include pain in the stung area and swelling. If your pet is having an anaphylactic reaction, you may see nausea, trouble breathings, and neurologic signs. Treatment consists of supportive care, and medications to reduce inflammation.
The common theme with all of the forms of bites is early treatment allows your pet to recover faster. Proper identification is key for establishing the proper treatment plan. Some of these venoms do not manifest until hours after the bite and are much more severe if allowed to develop. Most animals recover quite well after a short stay in hospital.
– Dr. McKenna