Lyme disease, a bacterial infection, is present in Oregon, and ticks in the state can carry the bacterium responsible for it. Understanding the specific tick species involved and their prevalence is important for residents and visitors. Knowing how to recognize symptoms and take preventive measures can help minimize exposure and address potential infections effectively.
Lyme Disease Presence in Oregon
In Oregon, the primary tick species known to transmit Borrelia burgdorferi, which causes Lyme disease, is the western black-legged tick (Ixodes pacificus). This small, brown-black tick is found predominantly in Western Oregon and along the Columbia River in lower elevations. The overall prevalence of infected ticks in Oregon is lower compared to regions like the Northeast or Upper Midwest United States.
Only a small percentage of western black-legged ticks in Oregon carry the Lyme disease bacterium, with estimates ranging from about one to eight percent. Both adult and immature ticks, known as nymphs, can transmit the disease; nymphs are tiny and harder to spot, often leading to undetected bites. For transmission to occur, an infected tick needs to be attached to a host for at least 24 to 48 hours. In recent years, Oregon has reported an average of 40 to 69 human cases of Lyme disease annually, with most diagnoses occurring during the summer months when ticks are more active.
Recognizing and Addressing Lyme Disease
Recognizing the early signs of Lyme disease is important for prompt treatment. The most common early symptom is a characteristic “bull’s-eye” rash, medically known as erythema migrans, which can appear as a circular or oval rash around the tick bite. This rash appears within one to four weeks after a bite but can emerge up to three months later, and it may gradually expand. The rash is not hot or itchy, and its appearance can vary, sometimes having a darker or lighter center.
Alongside the rash, individuals may experience flu-like symptoms such as a high temperature, chills, headache, muscle and joint pain, and fatigue. If a tick bite is discovered, remove the tick properly using fine-tipped tweezers by grasping it as close to the skin as possible and pulling upward steadily without twisting or crushing it. After removal, clean the bite area with antiseptic or soap and water. Seeking medical attention is advised if a tick bite is followed by any of these symptoms, as early diagnosis and treatment with antibiotics can prevent more severe complications.
Protecting Yourself from Ticks
Taking preventative measures can significantly reduce the risk of tick bites. When spending time outdoors, especially in wooded, brushy, or grassy areas, wear long-sleeved shirts and long pants, tucking pant legs into socks to create a barrier. Choosing light-colored clothing can also help make ticks more visible if they attach. Staying in the center of trails when hiking helps avoid brushing against vegetation where ticks may be waiting.
Using EPA-registered insect repellents containing active ingredients like DEET, picaridin, or oil of lemon eucalyptus on exposed skin can deter ticks. Treating clothing and gear with products containing 0.5% permethrin provides further protection, as permethrin acts as an insecticide and repellent. After returning indoors, perform a thorough full-body tick check, paying attention to areas like the groin, armpits, and scalp. Tumble dry clothes on high heat for at least 10 minutes to kill any ticks. Showering within two hours of coming indoors can wash off unattached ticks.