In some cases, an ant invasion is just a nuisance. No one likes opening their cabinet to find a line of ants marching to and from a box of cereal or bag of sugar. Occasionally, though, ants can pose a more serious threat. Certain species are known to carry bacteria on their bodies, and these bacteria can potentially contaminate the food that the ants come into contact with.   Carpenter ants can cause structural damage to your home, much in the same way that termites would. Meanwhile, the bite of a fire ant can result in an intensely painful reaction, including a potentially life threatening allergic reaction in sensitive individuals.