Outdoor enthusiasts and those enjoying Arizona’s diverse landscapes often encounter various insects, leading to questions about potential nuisances like chiggers. While many associate chiggers with humid, eastern climates, these tiny mites are indeed present in Arizona. Understanding what chiggers are, where they reside, and how to manage their bites is important for anyone spending time outdoors in the state.
Understanding Chiggers
Chiggers are the larval stage of tiny mites, sometimes called harvest mites or red bugs, and are nearly invisible. These six-legged larvae are the only stage that feeds on humans and animals, and are much smaller than a period. In North America, including Arizona, chiggers do not burrow into the skin; instead, they attach to a hair follicle or pore. They inject a digestive enzyme that breaks down skin cells, which they then consume as a liquid meal.
A few hours after being bitten, intense itching typically begins, often accompanied by red bumps that may resemble pimples, blisters, or hives. These bites frequently appear in clusters, particularly around areas where clothing fits tightly, such as ankles, waistbands, or behind the knees. Chiggers in the United States do not transmit diseases, distinguishing them from species found elsewhere.
Where Chiggers Thrive in Arizona
Chiggers are common in Arizona, particularly in areas offering moisture and dense vegetation. They are found in residential grass lawns, parks, and natural preserves where plants are abundant. These mites prefer habitats with tall grasses, weeds, and brush, including wooded areas and forest edges.
Riparian zones and areas near lakes and rivers also provide ideal conditions for chiggers due to increased humidity and lush plant growth. While often encountered in southeastern Arizona’s mountain ranges, chiggers have also been reported in northern areas like Pinetop and along the Verde Rim. Chigger activity peaks during warmer months, from late spring through early fall, when temperatures are between 60 and 99 degrees Fahrenheit, and vegetation is fullest.
Preventing Chigger Bites
Preventing chigger bites involves creating physical barriers and using repellents when spending time outdoors. Wearing long-sleeved shirts and long pants made of tightly woven fabric helps deter mites from reaching the skin. Tucking pant legs into socks or boots further minimizes exposed skin, particularly around the ankles. Applying insect repellents containing DEET to exposed skin and clothing can provide effective protection, with 10% to 30% DEET recommended.
For clothing and outdoor gear, permethrin-based sprays offer another layer of defense, as permethrin kills chiggers upon contact, though it should not be applied directly to the skin. Staying on cleared paths and avoiding walking through tall grass or dense brush can significantly reduce exposure. After returning indoors from outdoor activities, showering promptly with soap and water helps dislodge any unattached chiggers. Washing all outdoor clothing in hot water immediately after use also helps eliminate any lingering mites.
Relief for Chigger Bites
If chigger bites occur, prompt action can help alleviate intense itching and prevent further irritation. Immediately washing the affected skin with soap and water is recommended to remove any chiggers that might still be attached. While the mites themselves are no longer present once itching begins, this initial wash can still provide some relief.
Over-the-counter anti-itch creams and ointments containing ingredients like calamine, hydrocortisone, menthol, camphor, or pramoxine can soothe the skin and reduce discomfort. Oral antihistamines, such as diphenhydramine, loratadine, or cetirizine, can also help manage the itching and inflammation from within the body.
Applying a cool compress or ice pack to the bites can provide temporary numbing and reduce swelling. It is important to avoid scratching the bites, as this can break the skin and lead to secondary bacterial infections. Chigger bites typically resolve on their own within one to two weeks, but if symptoms worsen, show signs of infection, or persist for an extended period, medical attention should be sought.