DIAGNOSING THE BITE
To make certain that a poisonous snake has caused the bite, first examine the wound for teeth marks. In a perfect bite by a poisonous snake (excluding the coral snake), the pattern will reveal two distinctly larger holes where the fangs have entered the flesh. There also may be two rows of smaller teeth marks between these punctures.
Furthermore, if the snake engages the lower jaw, two additional rows of small teeth impressions will be seen below the first group.
Frequently the bite pattern is not a clear one. For example, if the snake pulls to one side as it disengages the fangs after a strike, the result is a series of scratch marks instead of punctures. There is also the possibility that the snake will engage only a single fang; or, perhaps, during fang replacement, two fangs are temporarily in position on one or both sides of the upper jaw. Any of these conditions, as well as others, can contribute to an obscure bite pattern.
The bite of a coral snake often is difficult to diagnose by examination of the wound. Because this snake impels its fangs in a sort of chewing motion, the pattern created by its bite may be two groups of closely spaced punctures where the fangs have entered the flesh a number of different times.
A clearly defined harmless snake bite pattern consists of a series of uniformly small punctures (four rows made by teeth in the upper jaw, two rows by teeth in the lower), but always without the large fang holes. More typically, a non-poisonous bite produces several rows of scratches.
Pit-viper poisoning is diagnosed primarily by the presence of local signs and symptoms. The most important of these are:
1. Pain accompanies most poisonous snake bites. Generally intense and burning in character, it becomes more severe with the passing of time. This symptom alone is not conclusive because pain can be imagined following a non-poisonous bite. Occasionally in a severe bite, the pain is replaced by numbness and tingling.
2. Swelling at the bite area is present in every case of poisoning. It will appear within five to 30 minutes. In a severe case, the swelling may continue to spread for 24 hours. There will be no swelling from a bite by a non-poisonous snake or by a poisonous snake that injected no venom.
3. Discoloration, reddish or bruise-like in appearance, begins around the fang punctures within a half hour and becomes gradually more extensive.
Intense local pain is symptomatic of coral snake poisoning but, unlike a case of pit-viper poisoning, swelling and discoloration are not pronounced. Diagnosis of coral snake envenomation is difficult and must be based primarily on systemic symptoms: headaches, weakness, lethargy and facial paralysis.