Chiggers, or “red bugs,” are the larval stage of mites from the family Trombiculidae. These microscopic arachnids are notorious for causing intensely itchy welts after they feed. A frequent misconception suggests that these mites burrow into the skin to lay their eggs. Chiggers do not lay eggs in human skin; the painful welts and severe itching are purely a reaction to their feeding process.
The Truth About Chiggers and Your Skin
Chiggers are six-legged larvae that emerge from eggs laid by the adult mite in damp soil or on vegetation. Only this larval stage is parasitic, seeking a host to obtain a meal before developing into its next life stage. After feeding for several days, the larva drops off the host and completes its development into an eight-legged nymph and then a harmless adult.
These mites are arachnids, related to ticks and spiders. Chiggers do not burrow into the skin or live beneath the surface. They attach to the skin for hours or days to feed on liquefied tissue. The intense discomfort is triggered by the feeding process and the body’s reaction, not from an infestation of mites or eggs under the skin.
How Chiggers Cause the Intense Itching
The intense itching associated with chigger bites results from the mite’s unique feeding strategy. The larva uses specialized mouthparts to create a tiny opening in the skin, injecting a salivary secretion containing digestive enzymes into the host’s tissue.
These enzymes break down the host’s skin cells, liquefying the tissue around the bite area. The host’s immune system reacts to this foreign substance by hardening the surrounding skin cells, forming a protective, tube-like structure called a stylostome. The chigger then uses this hardened tube as a feeding straw to suck up the digested tissue slurry.
The severe, persistent itching is caused by the combination of the allergic reaction to the injected enzymes and the irritation from the stylostome itself. This structure can remain embedded in the skin long after the chigger has detached, continuing to cause irritation until the body naturally dissolves and absorbs the hardened tissue. The resulting red welts and bumps, which can resemble blisters or hives, are the body’s delayed reaction, typically appearing several hours after the chigger has begun feeding.
Immediate Treatment for Chigger Bites
Once bites are noticed, the first step is to remove any attached chiggers by thoroughly washing the affected areas with soap and water. Scrubbing the skin with a washcloth while showering helps ensure all remaining larvae are dislodged.
Treatment for the resulting welts focuses on reducing inflammation and controlling the severe itching. Over-the-counter anti-itch products, such as calamine lotion or hydrocortisone creams, can be applied directly to the bites to soothe the skin. Taking an oral antihistamine can also help minimize the body’s allergic reaction and provide relief, particularly if the itching is interfering with sleep. Applying a cold compress or ice pack to the itchy areas may offer temporary relief from the discomfort and irritation.
Effective Strategies for Preventing Chigger Contact
Proactively avoiding chigger bites centers on minimizing contact with their preferred habitats. Chiggers are typically found in areas with tall grasses, dense weeds, and thick vegetation, such as along the edges of woods, fields, and water sources. Keeping lawns mowed short and trimming back shrubbery around the home can help reduce the local chigger population.
Wearing protective clothing is an effective barrier when entering infested areas. Long-sleeved shirts and pants should be worn, with pant legs tucked into socks or boots to prevent mites from crawling onto the skin. Insect repellent containing DEET is highly recommended for application to exposed skin and clothing. For stronger defense, clothing can be pre-treated with permethrin, a repellent that kills chiggers and remains effective through several washings.