Chiggers are small red pests from the mite family. They are about 1/60 of an inch (.04mm) and are found through out the world.
During their larval stages chiggers feed on skin cells. They crawl on to their host and use a digestive enzyme to loosen the skin. Chiggers do not actually bite. The enzyme used to break up the skin causes skin irritation, the severity of the irritation or rash depends on a number of factors like how man chiggers and the hosts natural reaction to the enzyme.
When chiggers have out grown skin cells the detach from their host and begin a transition stage called the nymph stage and eat plant material.
At adulthood chiggers become predators eating small insects and their eggs.