Loudoun County

Lyme Disease/Tick-borne Diseases

What is Lyme disease?

Lyme disease is caused by bacteria that some people get after being bitten by ticks infected with an organism named Borrelia burgdorferi. It was first identified in the 1970s in Lyme, Connecticut.

How common is Lyme disease in Loudoun County?

In 2009, Loudoun County reported 201 cases of Lyme disease, representing approximately 22% of the cases reported in Virginia that year. This represents a decrease in the number of reported cases from the prior two years of 293 in 2007 and 235 in 2008. Information on the current Lyme disease case definition is available from the Centers for Disease Control and Prevention.

Where is the organism that causes Lyme disease found?

The organism is maintained in wild rodents, deer, other mammals and certain ticks, most commonly the black-legged (deer) tick. It is transferred to people by the bite of an infected tick.

Who gets Lyme disease?

People of any age and in any part of Loudoun County can get Lyme disease. Infections occur throughout the year, but are more common during the late spring and summer and in people who work or play outdoors. Dogs, cats and horses can also get Lyme disease.

How is the organism spread?

The bacteria that cause Lyme disease are spread by ticks. Blacklegged ticks require a minimum of 36 hours attachment (feeding) before they can transmit Lyme disease.

You cannot get Lyme disease from animals or other people.

Rodents, particularly the white-footed mouse, are the most common reservoirs of Lyme disease.


What are the signs and symptoms of Lyme disease?

In most people, the first evidence of Lyme disease infection consists of a “bulls eye” skin rash at the site of the tick bite or developing such flu-like symptoms as fatigue, fever, headache, stiff neck, muscle or joint pain within 3 to 30 days after being bitten by an infected tick. The “bulls eye” rash, called erythema migrans (EM), is red and slowly gets bigger, usually with a clearing in the center; it is not painful and does not itch.

Bull's eye rash

(View enlarged image.)

Both the rash and flu-like symptoms may last up to several weeks and will go away with or without treatment. If the early infection is not treated though, other problems may develop such as nervous system disorders, heart problems, or joint swelling and pain.

How can Lyme disease be prevented?

There is currently no Lyme disease vaccine available for people. The best way to prevent getting Lyme disease is to reduce your chances of getting bitten by a tick and making sure that no tick is attached for more than a day. Steps you can take include:

    • Avoid tick-infested areas, such as tall grasses, whenever feasible.
    • When this is not possible, wear light-colored clothing with long sleeves and long pants and tuck pants into socks.
    • Clothes may be pretreated with a tick repellent called permethrin. Other tick repellents are available for treating the skin. Be sure to follow label instructions before using any repellent. The University of Arizona has prepared a useful publication on insect repellents, which is online:
    • Do a tick check whenever you return from a potential tick habitat and at least once a day. Remove any attached ticks promptly and carefully by gripping the tick with tweezers as close to the skin as possible and using a gentle steady pulling action. Protect hands with gloves, cloth or tissue when removing ticks from people or animals.
    • Keep ticks off your property by controlling deer and mouse populations - making your property less tick friendly - and considering annual pesticide application. More information on tick proofing your property is available in the Tick Management Handbook


What should I do if I think I have Lyme disease?

You should contact your doctor if you have an unusual rash, other signs or symptoms of Lyme disease, or if you believe that you have had a black-legged tick attached to you for at least 36 hours.

The Health Department does not recommend having ticks tested for infection with the bacteria that causes Lyme disease.

Source of photos: Centers for Disease Control and Prevention (CDC)

Other Resources

Loudoun County Government

P.O. Box 7000 • Leesburg VA 20177