Posted by: Footler PJ4 SEP 2013
Pharmacists pride themselves on being available to offer advice and answer questions. These questions may be disconcerting (“What is taking so long? It’s only a few pills!”) or they may be unexpected. “Do birds have taste buds?” is one I recall. (They do, but relatively few).
One recent question was about the difference between jiggers and chiggers. The jigger, Tunga penetrans, also known as chigoe flea, is a parasitic arthropod found in tropical and subtropical areas. It lives in soil and sand but feeds on warm-blooded hosts, including humans. The breeding female flea burrows head first into the host’s exposed skin — often the feet, although any part of the body can be affected. The tip of the flea’s abdomen remains exposed to enable it to breathe and defaecate while feeding on the host’s blood. Several dozen eggs develop during the following two weeks. They can cause intense irritation (tungiasis), secondary infections, toe deformation and nail loss. The eggs fall to the ground when ready to hatch, whereupon the flea dies.
Chiggers have nothing to do with chigoe fleas. They are the larval form of a family of mites, the Trombiculidae, which live in more temperate areas, including forests, grasslands, golf courses and damp areas around lakes and streams. In the UK, western Europe and eastern Asia the best known chigger is Trombicula autumnalis, also called the harvest mite. Other species are found in North America and Australia.
The larval mites feed on the skin cells, not blood, of various animals, including humans. They do not “bite” but inject digestive enzymes to break down skin cells while feeding through a hole formed in the skin. This causes severe itching. Eventually, the larvae fall from the skin to mature into adults, which feed on plant materials and are harmless to humans.