AUGUST
2006

 

By
Tom Turpin
 
Professor of
Entomology
Purdue University

 

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Check out these books by Tom Turpin:

Flies in the face of fashion

What's Buggin You Now?

 

 

 

8-24-06

Download the audio of On Six Legs: MP3, WMV.

A Good Year for Chiggers


If you have ever had chiggers, you know what this article is about. If not, consider yourself lucky! Chiggers have been known to make outdoors people, including hikers, picnickers, wild-blackberry pickers or even lawn-sitters miserable. Given the chance, these creatures will feed on us and, in the process, produce an itchy, red welt. And this is why we don't like chiggers.

These pests are not insects; they are mites. The name chigger, or jigger as they are sometimes called, is based on the word chigoe or flea. Chiggers have also been called "red bugs," because of their red or orange color. Chiggers are very tiny creatures, smaller than newsprint periods. But even though they are small, chiggers create a lot of misery when attacking humans.

Here's the scoop on chiggers. Several species of these mites exist in the United States. The adult stage is not parasitic and spends the winter in the soil. On the first warm days of the spring, the adult crawls from the soil and deposits eggs. The eggs hatch into the juvenile stage. It is this stage that attacks animals.

The immature chigger crawls upon plants and waits until an animal comes by. The hungry chigger drops or crawls onto the unfortunate host and begins to look for a feeding site. On humans, chiggers often end up where clothing fits tightly to the skin. Such locations as waistbands, collars, bras and tops of socks are prime locations for chigger feeding. In addition, wrinkled skin, such as in ankles, armpits, back of the knees and elbows, is frequently attacked.

The baby chigger doesn't take blood from the host. It feeds by injecting digestive juices into the skin of the animal and then sucking up the partially digested cells. Within three to four hours, a red, itchy welt will develop at the feeding site. The chigger will feed for three to four days before dropping from the host. But the welt and the itching can continue for a week or longer.

As anyone who has ever been the victim of chiggers knows, these little mites can create more misery for their size than almost any creature known. To be sure, the damage they do to humans is not a major medical problem. But having chiggers is not something we are likely to forget.

So what can you do to avoid getting chiggers? The first thing is to avoid locations where chiggers are likely to be found. In general, chiggers are more common in damp areas with tall grass or weeds. If frequenting such habitats, avoid wearing sleeveless shirts, shorts and sandals. It is also a good idea to tuck pant legs into boots and button collars and cuffs.

When returning from locations that might harbor chiggers, remove clothing as soon as possible. A warm soapy shower will also reduce the number of bites that you receive. Chiggers can stay in clothing, so it is advisable to launder in hot water any clothing that was worn on outdoor jaunts before wearing again. The use of insect repellents prior to entering chigger-infested habitat is also effective in reducing incidents of chigger bites.

Chigger infestations can vary widely from spot to spot within infested areas. For instance, a 10-square-foot section of a lawn might have a heavy infestation of chiggers while the rest of the lawn has none. This means that, on occasion, people sitting in one section of a lawn will all get chigger bites while others nearby will receive no bites at all.

Once a chigger has started feeding, there is not much you can do. Treating with ointments useful to reduce itching will provide some temporary relief. But, generally, if you have managed to become a host to a group of chiggers, you will experience a week to 10 days of itching and discomfort. But don't think you are special if you have managed to get chiggers. Chiggers aren't choosy about their food sources. Small mammals, snakes, turtles and birds also serve as hosts to these little mites.

 

 

Writer: Tom Turpin
Editor: Olivia Maddox