A recently released OSHA hazard information bulletin* (HIB) provides guidance for people who reside in high or moderate risk areas in the U.S. and who are exposed to ticks during the course of their work and thus are at risk of contracting Lyme disease. In addition to railroad work, examples of outdoor work noted by OSHA which may be associated with increased risk of exposure to infected ticks include: construction work, landscaping, forestry, brush clearing, land surveying, farming, oil field work, utility line work and park/wildlife management.

Lyme disease is caused by Borrelia burgdorferi, a bacterium carried in the gut of certain ticks. When these infected ticks attach to the human body (often in armpits, groin, scalp, or other hairy, hidden body areas), they slowly feed, and within 36-48 hours they may transmit B. burgdorferi to their human host. Young ticks are especially abundant and seeking hosts in late spring and early summer, although adult ticks can transmit infection as well.

The Center for Disease Control and Prevention (CDC) estimates that the number of annually reported cases of Lyme Disease has increased 33-fold since national surveillance began in 1982 (based on 16,801 cases in 1998 versus 497 cases in 1982). While cases of Lyme disease have been reported in 48 of the 50 states as well as the District of Columbia, the CDC has developed a national Lyme disease risk map in which CDC identified areas of the U.S. as minimal or no risk, low risk, moderate risk, or high risk for predicted Lyme disease.

The states that include areas with the highest risk are those in the northeast U.S., from Massachusetts to Maryland; the north-central region including Wisconsin and Minnesota; and an area in northern California in the pacific-coastal region. There is a high prevalence of B. burgdorferi in the tick population in these areas and therefore an increased risk of acquiring Lyme disease from a tick bite. The remainder of the states have no or few ticks infested with B. burgdorferi and are considered low, minimal, or no risk for Lyme disease.

Although a majority of people with Lyme disease develop a "bulls-eye" rash, 20-40% of persons who have the disease do not have the rash. Other signs and symptoms may be non-specific and similar to flu symptoms (e.g., fever, lymph node swelling, neck stiffness, generalized fatigue, headaches, migrating joint aches, or muscle aches).

Diagnosis is based on a history of known exposure and development of clinical signs and symptoms, with blood testing providing valuable supportive information. Most cases of Lyme disease can be successfully treated with antibiotics. It is very important that Lyme disease be diagnosed and treated with antibiotics, since untreated Lyme disease may result in symptoms (i.e., arthritis, muscle pain, heart disease, brain and nerve disorders) that are severe, chronic and disabling.

The "first line of defense is decreasing the probability of tick bites," says OSHA's HIB. "Ticks can be vectors of other infections, in addition to Lyme disease." Steps to take include:

Ø Avoidance of tick habitat (brushy overgrown grassy and woody areas) particularly in spring and early summer when young ticks feed.
Ø Removal of leaves, tall grass and brush from areas around work areas or residential areas to decrease tick as well as host (deer and rodent) habitat.
Ø Application of tick-toxic chemicals to surrounding work or residential areas in accordance with federal, state and local regulations and community standards.

Personal protection steps to take include:

• Wearing light-colored clothing (to more easily see ticks).
• Wearing long-sleeved shirts, tucking pant legs into socks or boots (delays ticks from reaching skin so they can be more easily found before attaching).
• Wearing high boots or closed shoes covering entire foot.
• Wearing a hat.
• Using appropriate insect repellants on non-facial skin and permethrin on clothes (kills ticks) in accordance with Environmental Protection Agency guidelines.
• Showering and washing/drying clothes at high temperature after outdoor exposure.
• Doing a careful body check for ticks, prompt removal with tweezers and skin cleansing with antiseptic.

* Important Information on the Nature and Effect of Hazard Information Bulletins - The Directorate of Technical Support issues Hazard Information Bulletins (HIBs) in accordance with OSHA instruction CPL 2.65 to provide relevant information regarding unrecognized or misunderstood health hazards, inadequacies of materials, devices, technique and safety engineering controls. HIBs are initiated based on information provided by the field staff, studies, reports and concerns expressed by safety and health professionals, employers and the public. Bulletins are developed based on thorough evaluation of available facts in coordination with appropriate parties. The HIB is not intended to address issues related to patient care. An HIB is not a new standard or regulation, and it creates no legal obligations. It is advisory in nature, informational in content, and is intended for use by employers seeking to provide a safe and healthful workplace.