To some people, there isn’t anything more irritating than small bumps around their ankles or knees that itch intensely. These small, itching bumps were probably caused by a chigger, according to the Missouri Department of Conservation.
"Chiggers are extremely tiny; you will need a magnifying glass to see them. Their presence is known by these itchy whelps located where the skin is most tender (ankles, back of knees, waistline, etc.)," states a release. "Their bites form a scab-like tube in response to the chigger’s irritating saliva. It is the larval stage that is parasitic and must feed on animal tissue before they molt into adulthood."
A chigger's primary food source of the larval stage is reptiles and birds, with mammals being a secondary host. Adult chiggers are adult red mites that feed on insect eggs and other smaller mites.
"Chiggers are found in brushy, grassy or weedy areas where any contact with the vegetation has the potential to allow the chiggers to climb onto you. Though irritating, chiggers do not carry any diseases, so they are not nearly as harmful as ticks and mosquitoes," states the release.
Once on board a person, chiggers can infiltrate the holes in most fabrics and are impeded by folds of flesh or barriers, such as elastic leg holes or waistbands, watchbands, backpack straps and sock tops. These help the chigger to press against a barrier and infiltrate your skin.
"Once the chigger has made an opening in your skin, it injects saliva to liquify the tissue and begin to ingest it. They will feed for three or four days if nothing interrupts their meal," states the release. "If you think you have been exposed to chiggers, take a shower or bath, this should remove most of them. If that isn’t available, rub yourself down with a towel, this will dislodge and crush most of them."
The longer a chigger is attached the longer the itching last, up to two weeks. You may need to treat the itching with an over-the-counter medication that contains antihistamines, analgesics or anesthetics.
Avoiding chiggers is difficult. Peak activity is April to October around dusk and dawn and when temperatures are in the 70s and 80s.
"To protect yourself, wear long-sleeve shirts and long pants, use insect repellent containing DEET, or pretreat clothes with permethrin. People have also relied on a dusting of sulfur, kerosene or citronella oil to ward off chiggers. If you do encounter a chigger bite, scratching is not advised. Scratching prevents the bite from healing and could cause a secondary infection," states the release.