Lyme disease is a bacterial infection caused by Borrelia burgdorferi, a spiral-shaped bacterium transmitted to humans through the bite of an infected tick. These arachnids act as vectors, picking up the bacteria from wildlife hosts and passing it on during a subsequent blood meal. Understanding the specific risk profile in South Carolina requires examining which species are active and what percentage of them carry the pathogen. This establishes the realistic level of exposure for residents and visitors throughout the state.
Lyme Disease Risk Assessment in South Carolina
South Carolina is officially classified by public health organizations as a low-incidence state for Lyme disease, a designation that reflects the comparatively low number of reported human cases annually. While the state does host the Blacklegged tick (Ixodes scapularis), the primary vector for the disease, the prevalence of the B. burgdorferi bacteria within this tick population is markedly lower than in the Northeast and Upper Midwest. In the northern United States, infection rates in the Blacklegged tick population can range from 30 to 50 percent, but studies suggest a much lower prevalence, often less than one percent, in southern populations.
This lower statistical risk is likely due to differences in the ecology and wildlife dynamics of the region. The transmission cycle, which involves ticks feeding on various reservoir hosts like rodents and birds, appears less efficient in the South. Despite the overall low state-wide average, B. burgdorferi has been confirmed as endemic in certain specific coastal foci within South Carolina. The state health department has historically reported an average of approximately eight cases of Lyme disease per year, confirming that the disease is rare but present.
South Carolina’s Primary Tick Species
The Blacklegged tick (Ixodes scapularis), often called the Deer tick, is the only species in the region known to transmit Lyme disease to humans. This tick is present across South Carolina, though typically in lower volumes than other species. Adult females are identifiable by their reddish-orange body and black scutum, contrasting with the dark coloration of their legs.
The Lone Star tick (Amblyomma americanum) is significantly more abundant in South Carolina and is the most frequently collected species. This tick is easily recognized by the distinct white or silvery-white spot on the back of the adult female. The Lone Star tick is not considered a vector for Lyme disease, but it does transmit other pathogens, including those that cause Southern Tick-Associated Rash Illness (STARI) and can trigger Alpha-gal syndrome, a red meat allergy.
Another common species is the American Dog tick (Dermacentor variabilis), which is associated with transmitting Rocky Mountain Spotted Fever. The Gulf Coast tick (Amblyomma maculatum) and the invasive Asian Longhorned tick (Haemaphysalis longicornis) are also encountered, each capable of transmitting different pathogens. Prompt identification and removal of any attached tick is prudent due to the presence of multiple tick species capable of transmitting various diseases.
Preventing Tick Bites and Proper Removal
Preventing tick bites begins with treating clothing and gear before heading into wooded, grassy, or brushy areas. Clothing, boots, and camping equipment can be pre-treated with products containing 0.5% permethrin for long-lasting protection. Skin should be protected by using an EPA-registered repellent containing active ingredients like DEET, with concentrations of 20% or more recommended for maximum efficacy.
When hiking, staying in the center of trails and avoiding tall vegetation minimizes direct contact with questing ticks. Upon returning indoors, a thorough check of clothing, gear, pets, and the body should be performed, with showering recommended within two hours to help wash off unattached ticks. Ticks often migrate to hard-to-see areas like the groin, armpits, and scalp, so these spots require particular attention.
If a tick is found attached, it should be removed immediately using fine-tipped tweezers. Grasp the tick as close to the skin’s surface as possible and pull upward with steady, even pressure, being careful not to twist or jerk the tick. Prompt removal is effective because transmission of the Borrelia bacteria typically requires the tick to be attached and feeding for 36 to 48 hours or more.
Early Signs of Lyme Infection
The initial presentation of Lyme disease often involves the appearance of the Erythema migrans rash at the site of the tick bite, occurring in approximately 70 to 80 percent of infected individuals. This rash typically begins 3 to 30 days after the bite and gradually expands, sometimes clearing in the center to create the classic “bull’s-eye” appearance. The rash can be warm to the touch but is rarely itchy or painful.
Even without the visible rash, early infection can cause non-specific flu-like symptoms. These symptoms include fever, chills, headache, fatigue, muscle aches, and swollen lymph nodes. These symptoms can be mild and easily mistaken for a common summer cold or flu.
If a person develops any of these symptoms after a known tick bite or after spending time in tick habitats, they should seek medical attention promptly. Early diagnosis and treatment with antibiotics are highly effective at preventing the infection from progressing to later, more severe stages. Recording the date of a tick bite can provide useful information for a healthcare provider if symptoms later develop.