The northern deer tick, Ixodes scapularis (formerly Ixodes dammini) is the principal vector in the North and Southeast of the spirochete, Borrelia burgdorferi. This is the spirochete that which causes Lyme disease (Lang 1993). Lyme disease symptoms have been reported throughout the US and the world for years, but it was not until the mid-seventies that Lyme disease was described and named. The first acknowledged report was in Lyme, Connecticut, in 1975, where the disease was manifested as epidemic arthritis (Lang 1993). Since then Lyme disease has been slowly recognized as a new epidemic of the same proportion as AIDS. Although Lyme disease rarely is a direct cause of death, misdiagnosis and delay can cause permanent disability. (See Table 1.) Lyme disease has been described as a "disease of morbidity" (Lang 1993). Since 1993, Lyme disease was not considered endemic in Maryland (Lang 1993), however, there were many reported cases in 1980, 1982-1986 (Ciesielski et al., 1988). An excellent summary article (July, 2000) on tick-related disease is available.

The chronic stage has active symptoms for three months or more, and includes most of the symptoms from the disseminated stages on a relapsing or chronic basis.

At the present there are no standard treatment protocols for Lyme disease (Lang 1993). In 1995 (Time Magazine July 24) doxycycline was listed as curative for Lyme disease and for Ehrlichiosis (another deer-tick related disease). A vaccine became available in 1998.

Characteristics

Habitat

Deer ticks (Ixodes scapularis) are found primarily in wooded habitats and most abundantly in mixed hardwood forests with extensive shrub layers (Schulze et al., 1988). Fields are rarely exploited until secondary woody succession develops and the creation of edge increases the abundance of the ticks. Currently, ticks are associated with the large tracts of undeveloped woodland, typical of federal, state, and county parks and wildlife refuges.

Life Stages

There are 3 stages: larvae, nymph, adult, to the life cycle of the tick (Anderson 1988). The larval and nymphal stage ticks are found primarily in rodent nests during May and June. Adult ticks are found on shrubs and on larger mammals in the fall, winter, and early spring.

Table 1. Lyme Disease Stages and Symptoms (Lang 1993). Lyme disease is divided into 3 stages. One person may pass from the early stage to the late disseminated stage within a few weeks, while another person will take months or even years to progress to that stage. The symptoms may overlap and vary.

Early	Early	Disseminated	Late	Chronic
EM Rash	Headache Joint Pains Body Aches Night Sweats Sensitivity to Light, Sound, Touch Migratory pains Bell's Palsy Fatigue Heart Palpitations Swollen Glands Stiff Neck Worsening of Asthmatic Symptoms Disorientation Lyme Fog Conjunctivitis Sleep Disturbances	Severe Headaches/Migraines Crippling Arthritis Swollen Joints Heart Blockage Hypersensitivity to Light, Sound, Touch Crippling Migratory Pains Severe Fatigue Optic Neuritis and Increased Eye Complications Seizures Nosebleeds Memory Loss Lyme Fog Dyslexic reversals Sleep Disturbances, Nightmares Abnormal MRI, CAT Scan, EEG, CSF	Loss of Libido Fatigue	Migrane Headaches Arthritis Muscle Weakness Lyme Fog Dyslexia

Host Animals

The deer tick may soon be found to feed on almost every species of land mammal except bats and every species of bird that forages on the ground (Anderson 1988). Although ticks of all stages can be found on all types of mammals, the larval and nymph's most important host is the white-footed mouse (Peromyscus leucopus), and the adults primary host is the white-tailed deer (Odocoileus virginianus). These specific hosts are of particular importance and it is hypothesized that the increasing prevalence of Lyme disease in eastern North America may be indirectly related to the rising number of deer.

Transmission of the Spirochete

Host animals may be infected (Anderson 1988) and it has been shown that people can get Lyme disease through exposure to the urine or blood of infected animals (Lang 1988). However, it is more common for the disease to be spread through tick attachment to the human. In order for the infection to be spread to humans, the tick must be connected to the human for 4 to 24 hours (Lang 1988). The greatest risk of infection is during the month of June during the nymphal stage (Schulze et al., 1988).

Collecting and Monitoring

Ticks have been collected by flogging vegetation (Burgdorfer et al., 1988) and by trapping animals and counting nymphs or adult ticks present (Mather et al., 1988). A cloth carrying dry ice (CO₂) used as a drag has been very effective in sampling over 20- to 50-meter transects. Ticks attracted to the cloth are counted.

Tick Control Methods

Acaricides

A study done in Massachusetts using permethrin-treated cotton (PTC) distributed in early May reduced the number of host-seeking nymphs. It was determined that PTC applied twice per season can reduce the risk of transmission of the Lyme disease causing spirochete (LDS) in areas where human exposure to LDS-infected ticks is intense (Mather et al., 1988). Using carbaryl and diazinaon to spray wooded areas in November reduced the number of adults throughout the winter (Spielman 1988), although the effect was limited to one year. Also, a fall spraying does not affect larvae and nymphs because they are not active at this time (Schulze et al., 1988).

Burning and Brush Clearing

Trial burning and mowings were shown to reduce the abundance of ticks by over 70% for 1 year. This type of treatment has only local application, and is site dependent (Schulze, et al., 1988). It was suggested that immediately following mowing there is an increase in tick numbers before the numbers decrease (Spielman 1988).

Host Reduction

The reduction of deer had little short-term effect on tick populations and mass exterminations would not be popular with the public (Schulze, et al., 1988).

Integrated Disease Management

Simultaneous use of the following 14 practices can reduce the occurence and danger of Lyme disease.

1. Use a vaccine approved by the FDA on December 21, 1998 for people age 15 to 70 (a 3-innoculation treatment)
2. Educate area users about peak tick periods (May to October).
3. Use repellents, e.g., DEET. This substance should be used in moderation on the skin, especially of children.
4. Make careful personal inspection and bathing to avoid 4-hour contact with tick.
5. Use protective clothing (long pants; long-sleeve shirts).
6. Avoid shrubs in peak periods.
7. Cut/mow shrubbery along jogging/hiking paths.
8. Monitor ticks (as described above).
9. Apply annually acaricides to vegetation to control adults in the fall and spring.
10. Disperse acaricide-treated nesting material throughout the late spring and summer to control nymphs and larvae.
11. Reduce deer herd to low levels (Schulze et al., 1988), and high deer health.
12. Allert local doctors to symptoms of the disease.
13. Publish a suggested treatment regimen for local doctors as soon as one is available.

Literature Cited

Anderson, J.F. 1988. Mammalian and Avian Reservoirs for Borrelia burgdorferi. Annals of the NY Academy of Sciences. 539: 180-191.

Burgdorfer, W., Hayes, S.F., and J.L. Benach. 1988. Development of Borrelia burgdorferi in Ixodid Tick Vectors. Annals of the NY Academy of Sciences. 539 172- 179

Ciesielski, C.A., Markowitz, L.E., Horsley, R., Hightower, A.W., Russell, H., and C. Broome. 1988. The Geographic Distribution of Lyme Disease in the United States. Annals of the NY Academy of Sciences. 539:283-288.

Lang, D. 1993. Coping with Lyme Disease. 1st Ed. Ontario, Canada. 256 pp.

Mather, T.N., Ribeiro, J.M.C., Moore, S.I., and A. Spielman. 1988. Reducing Transmission of Lyme Disease Spirochetes in a Suburban Setting. Annals of the NY Academy of Sciences. 539: 402-403.

Schulze, T.L., Parkin, W.E., and E. M. Bosler. 1988. Vector Tick Populations and Lyme Disease. Annals of the NY Academy of Sciences. 539:204-211.

Spielman, A. 1988. Prospects for Suppressing Transmission of Lyme Disease. Annals of the NY Academy of Sciences. 539:212-220.

Subject: Lyme Disease Vaccine available (Information from the Vaccine Producer)

LYME-L: http://home.ease.lsoft.com/archives/lyme-l.html

First Lyme Disease Vaccine LYMErix(TM) Approved by FDA

SmithKline Beecham to Make New Vaccine Available Shortly

PHILADELPHIA, Dec. 21 /PRNewswire/ -- LYMErix(TM) [Lyme Disease Vaccine (Recombinant OspA)], manufactured by SmithKline Beecham Biologicals, today received approval from the U.S. Food and Drug Administration (FDA) for the prevention of Lyme disease.

LYMErix(TM), the world's first vaccine to prevent Lyme disease, has been proven effective in the prevention of both definite Lyme disease (characteristic symptoms with serologic diagnosis) and asymptomatic infection (no symptoms, but serologic diagnosis of infection).

Lyme disease, an emerging infectious disease, is a potentially serious multi-stage bacterial infection with a wide range of symptoms -- from a characteristic skin rash and flu-like symptoms to arthritis and heart abnormalities.

"The approval of LYMErix(TM) is especially significant for people who live in or travel to Borrelia burgdorferi-infected, tick-infested areas, or people who enjoy outdoor activities in these areas," said Dr. Vijay Sikand, clinical trial investigator and adjunct assistant professor of medicine, Tufts University School of Medicine.

"Now that a vaccine will be available, at-risk individuals should start getting vaccinated against Lyme disease in order to begin building immunity for the upcoming Lyme disease season."

Lyme disease has rapidly become the most common tick-borne illness, with cases reported in 48 U.S. states. Over 99,000 cases have been reported to the Centers for Disease Control and Prevention from 1982 to 1996. People at highest risk include those living in, working in or traveling to endemic areas in the U.S., including the Northeast, upper Midwest and Pacific coastal areas. According to a recent study published in Clinical Therapeutics, the economic burden of Lyme disease in the United States is projected to be $2.5 billion in direct and indirect medical costs over a five-year period.

Efficacy in the Prevention of Lyme Disease

LYMErix(TM) [Lyme Disease Vaccine (Recombinant OspA)] was evaluated in a landmark clinical trial that enrolled 10,936 individuals ranging from 15 to 70 years of age at 31 U.S. sites in endemic areas. Results from the multi- center, double-blind, placebo-controlled clinical trial demonstrated vaccine efficacy rates of 78 percent against definite Lyme disease and 100 percent against asymptomatic infection after three doses (after two doses, vaccine efficacy rates were 50 and 83 percent, respectively). Study participants received three doses of LYMErix(TM) or placebo on a 0, 1 and 12 month schedule. Compliance in the study was high with 95 percent of participants completing the 20-month study. "This action by the FDA is an important milestone in the prevention of Lyme disease," said Eddie Gray, vice president and director, SmithKline Beecham's U.S. Vaccine Business Unit. "The approval of LYMErix(TM) means the threat of Lyme disease may be significantly reduced for millions of Americans who spend time outdoors or plan to travel to endemic areas."

LYMErix(TM) is a genetically engineered vaccine that contains lipoprotein OspA, an outer surface protein of the causative Lyme disease bacterium, Borrelia burgdorferi. A novel hypothesis has been proposed to explain the effectiveness of lipoprotein OspA vaccination:

when infected ticks bite humans who have been vaccinated with LYMErix(TM), the vaccine-induced antibodies are taken up by the tick and interact with the Borrelia burgdorferi in the midgut of the tick,thereby preventing transmission of the organism to the host.

LYMErix(TM) may be associated with local injection-site reactions including redness and swelling, flu-like symptoms, arthralgias and myalgias. LYMErix(TM) should be available within weeks. For more information on Lyme disease and LYMErix(TM), call toll-free 1-888-LYMERIX, ext. 500.

Lyme Disease: A Widespread and Potentially Debilitating Disease

Lyme disease is a multi-stage disease caused by infection with a spiral- shaped bacterium (called a spirochete) known as Borrelia burgdorferi, which is carried by ticks that transmit the infection from animals to humans. Experts believe Lyme disease may be underreported by as much as 12 times (Maryland). In Connecticut, data indicate that, at best, only 16 percent of Lyme disease cases were reported over one year.

The onset of Lyme disease is commonly associated with a characteristic skin rash known as erythema migrans (EM), which can vary in size and location. EM is often accompanied by flu-like symptoms including headache, fever, fatigue,joint aches, muscle aches and a stiff neck. When diagnosed early, Lyme disease can usually be successfully treated with antibiotics without any long-lasting complications. However, diagnosis can be difficult because symptoms may imitate other illnesses.

If undetected and left untreated, the Lyme bacteria can spread to other parts of the body months to years following a tick bite and progress to late- stage Lyme disease. The bacteria can affect the joints, tendons, heart or nervous system, potentially resulting in arthritis, heart abnormalities such as heart block and myocarditis (inflammation of the muscular walls of heart) and Bell's palsy (paralysis of one or both sides of the face). Previous infection with Borrelia burgdorferi may not confer protective immunity. Therefore people with a prior history of Lyme disease may benefit from vaccination with LYMErix(TM) [Lyme Disease Vaccine (Recombinant OspA)].

In addition to getting vaccinated with LYMErix(TM), people can decrease their risk by avoiding tick-infested areas, tucking in pants and shirts, wearing light-colored clothing to spot ticks, using insect repellent containing DEET, and checking family members and pets for ticks.

SmithKline Beecham (NYSE: SBH) -- one of the world's leading healthcare companies -- discovers, develops, manufactures and markets pharmaceuticals,vaccines, over-the-counter medicines and health-related consumer products,and provides healthcare services including clinical laboratory testing, disease management and pharmaceutical benefit management. For company information, visit SmithKline Beecham on the World Wide Web at http://www.sb.com.