| Past What's Hot Index |P&PDL Home Page |
Timothy J. Gibb
|Line drawing of a chigger (magnified many times)|
Americans should not have to tolerate rude behavior, especially from something as small as a chigger! And yet, that is just what we are exposed to every summer from May through September in Indiana. Chiggers are immature mites, so tiny that they are seldom seen. Several can actually fit on the period at the end of this sentence. Chiggers most often occur on the tips of tall grasses, shrubs and weeds where they wait to drop off onto any large animal that happens to brush by. Usually these animals are birds, amphibians or small mammals but the mites are just as happy with the odd human that passes by. Typically chigger mites fall onto shoes or pant legs where they begin climbing in search of some tender, moist, skin to bite. They seem to concentrate in areas where clothing fits tightly against the body, such as around the ankles, groin, waist or armpits. This is exactly the rude behavior that I am talking about. A simple bite on an arm or back of the neck may be acceptable, and can be itched in public. But public itching of the groin area, the armpits or under the bra strap is an entirely different matter. It is socially unacceptable, politically incorrect and may even be illegal in some countries.
And itch you must. Once chiggers bite, there is no alternative. Chiggers do not burrow into the skin but rather pierce skin cells with their mouthparts and inject their special chigger saliva. This saliva contains enzymes that breaks down cell walls and causes the skin cells to liquefy. Human immune systems react to this foreign enzyme, resulting in not only infuriatingly, and intense itching but also in the formation of a hard red wall at the spot of the bite. The chigger capitalizes on this body reaction -- uses the round wall, called a stylostome as a straw to suck up its meal of dissolved body tissues, and then promptly drops off immediately after feeding. The itching intensifies, however, over the next 20 to 30 hours and may go on for days or weeks, depending on the person.
So, how does one stop chigger bites from itching? Well, aside from amputation, Physicians can sometimes prescribe an antiseptic/ hydrocortisone ointment. This may help ease the itch and reduce chances of secondary infections caused by the itching and scratching -- but it is never a perfect solution. The best solution is to avoid getting into chiggers in the first place. Stay away from tall grasses and shrubs if possible. Chiggers love to live in brambles, as most people who pick black raspberries know. They also inhabit grasses close to the ponds and streams where fishermen stand. If you must go in those areas, tuck your pant legs into your socks and apply insect repellant containing DEET to the shoe and ankle area. This will stop many of the mites from beginning their climb to areas where clothing fits tightly. (Theoretically, avoiding tight fitting clothes or going naked might help. If nothing else, it will certainly confuse the little biters -- not to mention friends and neighbors).
One of the most effective methods of preventing chigger bites is to change clothes and take a hot soapy shower as soon as possible after being in chigger-infested areas. The mites are so small that it may take them several hours to crawl from shoes to where they want to bite. Often they require several hours to crawl from shoes to where they want to bite. Washing them away with a sudsy, shower before they arrive is the most effective method.
The information given herein is supplied with the understanding that no discrimination is intended and no endorsement by the Purdue University Cooperative Extension Service is implied. Any person using products listed assumes full responsibility for their use in accordance with current direction of the manufacturer. Purdue University is an equal opportunity/equal access institution.
Information listed is valid only for the state of Indiana.
[Top of page | Past What's Hot Index | P&PDL Home Page]
The Plant & Pest Diagnostic Laboratory at Purdue University.