Lyme disease 101: Q&A with Dr. Sarah Gunter
Lyme disease is a tick-borne infection that affects many annually. While Lyme disease is not as prominent in Texas, people are still at risk. Dr. Sarah Gunter, assistant professor in the National School of Tropical Medicine at Baylor College of Medicine, discusses the diagnosis.
Question: What is Lyme disease?
Answer: Lyme disease is an infection that is caused by bacteria, typically Borrelia burgdorferi, that is transmitted by ticks. When an infected tick bites you and attaches over the course of 24 to 48 hours, it transmits the bacteria that causes infection and makes you sick.
Tick-borne diseases are a predominant source of vector diseases in the U.S. They account for more than 70% of our vector-borne diseases, and the majority of those are caused by Lyme disease.
Transmission of Lyme disease occurs mostly in the northeastern portion of the U.S. Lyme disease is not the only tick-borne disease that is of concern in the U.S. Diseases like spotted fever group rickettsiosis, ehrlichiosis, anaplasmosis and tick-borne viruses are also found. Even if you live outside of the region where Lyme disease is transmitted, you may still be at risk for tick-borne illness.
Q: How do you contract it?
A: Lyme is transmitted by the deer tick or the black-legged tick. Once the tick bites a person, it stays attached for several days. Over the course of 24 to 48 hours, the tick will transmit disease if it is infected.
Q: Where do the ticks live?
A: There are a lot of different tick species in the United States, but only a handful of these routinely bite humans and are capable of transmitting disease. Each tick has its own preferences on where it lives. In general, ticks like to live in shady and moist areas. When they are looking for a meal, they will climb up brush, shrubs or tall grass and reach their top legs out in a motion called questing.
In the U.S., Lyme disease is transmitted primarily by the black-legged tick. The black-legged tick is not found everywhere – it has a distribution throughout the eastern portion of the U.S., with the majority of Lyme disease transmitted in the Northeast.
Q: What are the symptoms?
A: People classically think of the bull’s eye rash called erythema migrans, which is a rash that occurs around the site where the tick bites you. People who contract Lyme disease might not get a rash – only 70 to 80% of people get the bulls eye rash – but it’s a tell-tale sign of the disease. People can also experience fever, headaches, muscle pain, joint pain and fatigue.
Talk to your primary care provider if you develop a fever or rash after being in an area where ticks are active. A physician can take a blood sample and look for your immune system’s response or antibodies against the bacteria.
Q: How do you treat it?
A: You can successfully treat Lyme disease with doxycycline, an antibiotic you take when you are suspected to have Lyme disease, or you are diagnosed with Lyme by a clinician. If it’s not treated, people can get a disseminated form of the disease, which can be more severe. If it disseminates, that can cause a severe clinical condition, such as heart or neurological conditions.
Q: Who is at risk?
A: The highest rate of disease transmission is in kids and older adults. People who are outdoors where ticks are active or in areas where its endemic (like the Northeast) are also at risk. We see transmission happening mostly in spring and summer months.
Q: How do you protect yourself?
A: Insect repellant, like those containing DEET, works for ticks. If you plan to be in an area where ticks are active, you can use permethrin on your clothes (not your skin), and it will protect you from ticks and mosquitos. Permethrin is good for several washes, so if you go camping or are outside for an extended period, this is a great option.
Q: Are other tick-borne illnesses as severe as Lyme disease?
A: While Lyme is an important source of tick-borne disease, it is by no means the only tick-borne disease. There are others we should be concerned about, such as spotted fever group rickettsioses, ehrlichiosis, anaplasmosis, babesiosis and more.
Much like Lyme disease, we are seeing increased rates of transmission of many of the tick-borne diseases being transmitted in the United States. Additionally, we are seeing certain tick species move into new areas of the country, putting new communities at risk for contracting disease.
Additional Resources: Texas Tick Project
By Homa Warren