Chiggers are the larval stage of mites, which are tiny arachnids related to ticks and spiders. These microscopic pests cause an intense, localized skin reaction resulting in small, red, itchy bumps on the skin. The severe discomfort leads many people to worry about permanent skin damage. While the bite itself rarely leaves a mark, lasting skin changes usually result from the body’s reaction and subsequent scratching. This article addresses the appearance of these bites, the science behind the intense itching, and the conditions under which a chigger bite may result in permanent scarring.
What Chigger Bites Look Like
Chigger bites are identified as small, red welts that may resemble pimples, blisters, or hives. These lesions do not appear immediately, but usually develop several hours later, often 12 to 24 hours after exposure. The delayed onset means the person is often unaware of the bite until severe itching begins.
The bites are frequently found in clusters or lines where clothing fits tightly against the skin, such as around the ankles, the waistline, or behind the knees. Chiggers attach to a host and crawl until movement is restricted by elastic bands or skin folds. The resulting red bumps can persist for up to two weeks before they fully resolve.
How the Bite Causes Intense Itching
The intense itching is the result of the body’s reaction to the mite’s feeding process. Chigger larvae do not burrow under the skin or suck blood. Instead, the mite uses its mouthparts to inject digestive enzymes into the skin tissue.
These enzymes dissolve the host’s skin cells, breaking them down into a liquid material the chigger ingests as food. The body’s immune response to this foreign material hardens the surrounding skin cells, creating a tiny, tube-like structure called a stylostome. The chigger feeds through this hardened tube until it is dislodged or finishes its meal. The stylostome and residual digestive enzymes trigger the intense inflammatory and allergic reaction, causing severe itchiness that begins within hours of the bite.
When Chigger Bites Lead to Scarring
Chigger bites rarely result in a true scar, which is permanent fibrous tissue replacing normal skin. The red bumps from the initial bite fade completely within one to two weeks without leaving a mark. The risk of scarring arises almost entirely from secondary trauma caused by the person.
Excessive scratching damages the skin barrier, creating open wounds that can become infected with bacteria. A secondary bacterial infection, such as impetigo or cellulitis, causes deeper tissue destruction that the body must repair with scar tissue. This is the most common path to a permanent, raised, or depressed scar.
Another skin change often mistaken for a permanent scar is post-inflammatory hyperpigmentation (PIH), especially in people with darker skin tones. PIH presents as a temporary dark spot or discoloration remaining after the initial inflammation subsides. This condition is the result of the intense inflammatory process itself, not fibrous scar tissue, and it fades over several months.
Treatment and Prevention of Scar Formation
The most effective strategy for preventing scarring is to intervene quickly and avoid scratching the affected areas. Immediately after exposure, thoroughly wash the skin with soap and warm water to remove any chiggers that may still be attached. This simple step prevents further enzyme injection and irritation.
To manage severe itching, apply over-the-counter hydrocortisone creams or calamine lotion directly to the bites. Oral antihistamines can also help reduce the body’s inflammatory response and lessen the urge to scratch, particularly at night. Controlling the itch avoids breaking the skin and introducing bacteria, preventing the secondary infection and deep tissue trauma that leads to true scarring.