Chiggers are not insects but are actually the tiny, six-legged larval stage of mites belonging to the Trombiculidae family. These microscopic arachnids are the only form that feeds on humans and other animals, causing an intensely itchy skin reaction. Despite the discomfort their bites cause, chiggers cannot spread from one person to another. The rash and itching a person experiences are the result of an isolated interaction between the mite and the individual host.
Why Chiggers Do Not Spread Between People
Only the larval stage is parasitic, requiring a single meal before dropping off the host to continue its development into a non-feeding nymph and then an adult. The larva attaches to the skin to inject digestive enzymes that break down skin cells, which it then consumes.
Chiggers do not burrow into the skin or stay permanently attached like lice or fleas. They typically remain attached for only one to four days, but they are often dislodged sooner by scratching or showering. Since the mite quickly detaches and requires environmental contact to find a new host, a person who has been bitten is not contagious. If multiple people are affected, it is because they shared exposure to the same infested outdoor area.
Understanding the Source of Chigger Infestation
Infestation begins when a person contacts vegetation where the chigger larvae are waiting for a host. These mites thrive in specific outdoor environments, particularly in damp, shaded areas with dense growth. Common habitats include tall grasses, weedy fields, berry patches, and the transitional edges between wooded areas and lawns.
The microscopic larvae climb onto grass blades or other low-lying vegetation, positioning themselves to transfer to a passing animal or human. Once a person brushes against the infested plants, the chiggers quickly move from the vegetation onto the host’s clothing or skin.
Post-Bite Treatment and Symptom Relief
Immediate action after potential exposure can help minimize the number of bites and severity of the reaction. Taking a shower promptly with soap and water is recommended, using friction to scrub the skin and dislodge any unattached larvae. Washing all exposed clothing in hot water will kill any mites still clinging to the fabric.
The intense itching and rash are caused by the body’s localized allergic reaction to the chigger’s digestive enzymes, which remain in the skin even after the mite is gone. Over-the-counter topical corticosteroids, such as hydrocortisone cream, can be applied to reduce inflammation and itching.
Applying calamine lotion or cool compresses can also provide soothing relief to the affected areas. Oral antihistamines, like diphenhydramine, may be taken to help control the systemic allergic response. Avoiding scratching is important to prevent secondary bacterial infections that can occur when the skin barrier is broken.
Proactive Strategies for Avoiding Chiggers
When entering areas known to harbor these mites, wear protective clothing that minimizes skin exposure. This includes long-sleeved shirts, long pants, and closed shoes, with pants legs tucked into socks to create a barrier.
Repellents containing DEET should be applied directly to exposed skin, following all manufacturer instructions. For clothing and gear, permethrin-based products are highly effective, but this insecticide should only be applied to fabric, not skin, and allowed to dry completely before wearing.
Managing the immediate environment by keeping lawns mowed short and removing dense weeds and brush around the yard can reduce chigger populations. By disrupting their preferred habitat, the likelihood of chiggers successfully transferring to a host is significantly diminished.