A mother brings her nine-year-old son to your office, along with the snake that bit him 20 minutes earlier. Which of the following, if identified during your examination of the snake, is most suggestive that the snake is poisonous?
- elliptical pupils
- a rounded head
- a double row of caudal plates
- the length of the snake
- the presence of a black band next to a red band
Answer: A
Elliptical pupils
There are two families of poisonous snakes: Viperidae is pit vipers, rattlesnakes, water moccasins, copperheads. They are distinguished by elliptical pupils vs. round in non-venomous snakes. Elepidae contains cobras, mambas, taipan and coral snakes. There are differentiated by their color bands, "red on yellow kills a fellow", "red on black, venom lack". Most poisonous snakes in the US - coral snakes. Mambas are the most poisonous in the world; cobras are hooded at the neck and are next most poisonous but neither of these are found in the U.S.
Know Your Content Blueprint
Animal and insect bites are covered as part of the PANCE Infectious Disease Blueprint