Lyme Disease-things you should know

Lyme disease is the most common tick-borne infection in the US, with more than 60,000 cases reported to the CDC in 2022.  Other methods of estimating disease indicate that there may be over 450,000 people diagnosed and treated for Lyme disease each year.

Lyme disease is mostly found in the northeast, mid-Atlantic, and upper Midwest areas of the US.  The bacteria Borrelia burgdorferi is transmitted to humans by bites from an infected blacklegged deer tick.

If infected after a tick bite, there are three stages that Lyme disease may progress in if left untreated.

In the first stage, which occurs less than 4 weeks after the onset of infection, a majority of patients will develop a rash at the site of the tick bite/attachment.  The rash is called erythema migrans, and appears as a red rash with a central clear zone (you can find examples of how the rash looks here).  The rash does not itch and does not hurt.  Some patients may also experience fever, swollen lymph nodes, and muscle aches.

If left untreated, the infection may spread in up to 60% of people.  Flu like symptoms with fevers, joint and muscle aches and lymph node swelling may occur over the next several weeks to several months.  The heart and nervous system may also become damaged, with heart muscle inflammation, abnormal heart rhythm, nerve damage/numbness, meningitis and facial paralysis possibly developing.

In the last stage (called late disseminated), an infected person may develop arthritis of large joints such as the knee, neurological damage and further skin damage including discoloration and thinning (atrophy).

Antibiotics are used to treat the infection.  Depending on the severity and stage of the infection, the antibiotics are given either by mouth or by IV (doxycycline is the first line therapy, with amoxicillin, cefuroxime, and ceftriaxone also being used).  If the infection is causing heart and nervous system effects, a hospital stay with IV antibiotics is usually necessary.

To diagnose Lyme disease, your doctor will ask you several questions about recent travel, known tick exposure, and your symptoms.  In the early stages, the appearance of the erythema migrans rash may be all that is needed to make a diagnosis.  If the rash is not known, but Lyme disease is thought to be likely, blood tests to check certain antibodies can be done.  The accuracy of these tests depends on the length of time since you were infected and may be falsely negative in the first few weeks of infection.

To avoid Lyme disease, prevention is key.  Reducing exposure to ticks is the best defense.  Ticks usually are found in grassy or wooded areas, and you may become exposed when engaged in outdoor activities such as walking your dog, camping or gardening.  Ticks may even be found in your own yard.

Treating your clothing and gear with 0.5% permethrin and using EPA registered insect repellants can be very effective.  If you find a tick attached to you, remove the tick as soon as possible by using clean fine tipped tweezers and pulling upward in a steady, even motion.  Clean the area with soap and water. Wash your clothing with hot water and tumble dry the clothes on high heat for about 10 minutes.

Contact your doctor and schedule a consultation to determine if further testing and treatment are required.   A one-time dose of antibiotic may be all that is needed if the tick is identified as a blacklegged deer tick, was attached less than 36 hours, and if the incidence of Lyme disease infection in your area is high.