Alexandria, Va., Oct. 2 -- In response to growing concern and confusion about Lyme disease, the Infectious Diseases Society of America (IDSA) has updated its Clinical Practice Guidelines on the disease, in order to provide guidance to physicians and patients based on the latest scientific evidence. The guidelines were originally published in 2000.

The most significant changes in the updated version include:

• The addition of information on human granulocytic anaplasmosis (HGA) and babesiosis, two diseases transmitted by the same tick that transmits Lyme disease;
• Recommendations of a single dose of an antibiotic for certain high-risk patients who have been bitten by a tick but do not have symptoms of Lyme disease;
• Expanded discussion and definition of so-called "chronic" or post-Lyme syndromes.

The Guidelines, developed by an expert panel according to widely accepted criteria for evidence-based medicine, contain updated information on the epidemiology, clinical features and diagnosis of Lyme disease, according to Gary P. Wormser, Chief, Division of Infectious Diseases and Vice Chairman of the Department of Medicine, New York Medical College. Dr. Wormser is lead author of IDSA's 2006 Lyme disease guidelines and chair of the expert panel that developed the guidelines.

At a Glance

• The Infectious Diseases Society of America has updated Guidelines to help physicians and patients in the diagnosis and treatment of Lyme disease.
• 95 percent of cases of Lyme disease are cured with 10 28 days of oral antibiotics.
• Long-term antibiotic treatment is not proven to be effective and may be dangerous.
• To be certain they get the proper medical care, patients who have lingering symptoms after proper treatment (those with so-called "chronic" Lyme disease) should ask their doctors if the diagnosis was accurate or if they may have a different or new illness.