What are the key symptoms of ant bite?

Sterile pustules: Fire ants cause the most distressing ant bites. They actually are stings, produced by the rear end of the insect, often in a circular pattern. There is intense stinging, and then later, after that subsides, you will see a clear blister with yellow pus inside. Don't break it. If you are allergic to the fire ants, you can have a lot of itching, swelling, or even throat closing, asthma and shock.