Lyme disease is caused by the bacteria Borrelia burgdorferi and the less common Borrelia mayonii. It is transmitted to humans by a bite from a black-legged tick, also known as the “deer tick”, which usually lives in long grass or heavily wooded areas. Deer ticks are commonly found in the Northeast and Midwest regions of the US.
According to the CDC, deer ticks must be attached to a person for 36-48 hours or more before the infecting bacteria can be transmitted. However, most deer tick bites come from immature or “nymph” ticks, which may be as small as a speck of dust. The CDC estimates that there are nearly 300,000 cases of Lyme disease reported every year, however, because many instances of Lyme disease go unreported, the CDC estimates that closer to 476,000 people contract Lyme disease every year.
Lyme Disease Symptoms
The symptoms of Lyme disease develop in stages. One of the first signs of Lyme disease is a red, expanding bulls-eye-shaped rash known as erythema migrans. This rash rarely itches or hurts, but it will grow over the course of several weeks. In some cases, the rash may expand to nearly 12 inches in diameter.
Symptoms that begin to develop with the onset of Lyme disease include:
- Fever
- Headaches
- Neck stiffness
- Body aches
- Fatigue
- Swollen lymph glands
As the disease progresses, or if the infection goes untreated, more serious symptoms may develop.
These symptoms include:
- Joint pain
- A recurring rash
- Inflammation of membranes surrounding the brain and spinal cord (meningitis)
- Facial paralysis (Bell’s palsy)
- Numbness (neuropathy)
- Irregular heart rhythms
If you have been bitten by a tick and are beginning to notice symptoms of Lyme disease, talk to your doctor right away. Most cases of Lyme disease can be effectively treated with medication. The earlier the treatment starts, the more effective it is.
Lyme Disease Risk Factors
Lyme disease is caused by a bite from a deer tick. That means you are at greater risk if you live in a hostipitable environment for these insects. Your risk of contracting Lyme disease is increased if you:
- Live in the upper midwest, northeastern, or mid-Atlantic regions of the United States
- Spend a lot of time outdoors, especially in spring or summer months
- Spend time in wooded or grassy areas
Lyme Disease Prevention
Lyme disease can be prevented with a few safety measures.
Prevention methods include:
- Avoiding wooded areas or areas with tall grass
- Walking in the center of nature trails to avoid contact with brush
- Wearing light colored clothing when going outdoors (so it's easier to spot a tick)
- Wearing long-sleeve shirts and long pants when going outdoors
- Applying insect repellant with DEET
- Spraying all clothing, shoes, tents and outdoors gear with an insect repellant that contains 0.5% permethrin
- Checking regularly for ticks
