Ticks, small arachnids related to spiders, are present in Arizona, despite the state’s predominantly arid environment. Over 25 different tick species have been identified across Arizona, though only a few are known to bite humans and transmit diseases. Understanding the types of ticks found in Arizona, their potential health risks, and effective protective measures is important for residents and visitors alike.
Common Ticks in Arizona
The brown dog tick (Rhipicephalus sanguineus) is the most common tick species found throughout Arizona, especially in central and southern regions like the Phoenix metropolitan area. These reddish-brown ticks appear grayish-blue or olive when engorged. While primarily infesting dogs, they readily bite humans. Brown dog ticks can complete their entire life cycle indoors, making them a common household pest found in cracks, crevices, and backyard clutter.
The Rocky Mountain wood tick (Dermacentor andersoni) thrives in Arizona’s cooler, higher-elevation areas like the Mogollon Rim and White Mountains. These oval, reddish-brown ticks have females with a white shield and males with gray and white spots. They prefer habitats with dense forests, lush meadows, and brushy areas, often found in foothills and mountains. Active from March through July, they feed on various mammals, including humans, deer, horses, and small rodents.
The Western black-legged tick (Ixodes pacificus) is less prevalent in Arizona due to its preference for cooler, more humid environments. Its distribution is limited to specific high-elevation areas, like the Hualapai Mountains, appearing in late winter and early spring. These small ticks have an orange-red body and black legs. They inhabit deciduous forests, shrubs, and areas near water sources, remaining active during milder winters without snow.
Tick-Borne Diseases in Arizona
Tick-borne diseases are relatively uncommon in Arizona, though they can lead to serious health concerns.
Rocky Mountain spotted fever (RMSF) is the most frequently reported tick-borne illness in the state, with annual case numbers usually below a dozen. The brown dog tick is the primary vector for RMSF in Arizona, with the Rocky Mountain wood tick also capable of transmission. Initial symptoms often mimic the flu, including fever, headache, and muscle aches, with a spotted rash appearing two to five days later. Early diagnosis and treatment are important, as untreated RMSF can progress to a severe, life-threatening condition.
Tick-borne relapsing fever (TBRF) is infrequent in Arizona, with few annual cases, though small outbreaks are noted. Transmitted by soft ticks, specifically Ornithodoros species, it is often linked to exposure in rustic, rodent-infested cabins in mountainous, high-elevation regions like the White Mountains. Symptoms include recurring episodes of fever lasting two to seven days, alternating with symptom-free periods of four to fourteen days. They may also involve chills, sweats, headache, and muscle or joint pain.
The Western black-legged tick is associated with Lyme disease, but the risk of contracting it in Arizona remains low. While rare cases of Lyme disease have been reported in the state, the majority of cases in the United States originate from the northeastern and north-central regions. Colorado tick fever (CTF), transmitted by the Rocky Mountain wood tick, presents with flu-like symptoms such as fever and muscle pain. CTF is milder than RMSF and often resolves without specific medical intervention.
Prevention and Removal
Preventing tick bites involves several practical steps when engaging in outdoor activities. Wear long-sleeved shirts, long pants, and closed-toe shoes to minimize skin exposure. Opt for bright or light-colored clothing to make ticks easier to spot. Apply insect repellent containing at least 20% DEET to exposed skin. When walking in vegetated areas, avoid brushing against bushes or tall grasses where ticks might reside.
After spending time outdoors, conduct thorough tick checks on yourself, family members, and pets. Pay close attention to areas like hairlines, behind the ears, armpits, and the groin. For pets, regular veterinary checks and frequent grooming help manage tick presence. Within your property, trimming vegetation like weeds, tall grass, and shrubs can reduce potential tick habitats.
If a tick is found attached to the skin, prompt and proper removal is important. Use fine-tipped tweezers to grasp the tick as close to the skin’s surface as possible, ideally at its head. Pull upward with steady, even pressure, avoiding twisting or wiggling the tick, as this could cause its mouthparts to break off in the skin. Do not squeeze the tick’s body, which could force infectious fluids into the bite site.
After removal, clean the bite area with rubbing alcohol or soap and water. Placing the removed tick in alcohol can kill it. If you develop any symptoms after a tick bite, or if you are concerned, consult a healthcare professional.