Lyme Disease Vaccine-Should I be Vaccinated? (res14)
Submitted by Fred Anderson, Epidemiologist, Washington County Department of Public Health and Environment.
On December 21, 1998, the Food and Drug Administration (FDA) licensed LYMErix by SmithKline Beecham, the first vaccine to aid in the prevention of Lyme disease for those persons 15–70 years of age. The purpose of this article is to give you current information about the epidemiology of Lyme disease in Minnesota and Wisconsin; review some of basic information on Lyme disease and discuss the current consumer information on LYMErix.
Lyme Disease
Signs and Symptoms
Lyme disease is caused by a bacteria (Borrelia burgdorferi), that is transmitted by infected deer tick (not the common wood tick). The deer tick (Ixodes scapularis) is also called the black-legged or bear tick. Lyme disease is an illness that may affect the skin, joints, nervous system, heart and other areas of the body. The most common symptom, three to 30 days following a tick bite, is a skin rash called erythema migrans or EM. The rash often has an irregular red ring-shaped appearance with a central clearing or a "bull's-eye". Some individuals may not notice or develop the rash. They may go on to develop other symptoms such as: fever and chills, headache, fatigue, muscle and joint pain.
Days or weeks later, the illness may progress and include one or more of the following symptoms: multiple EM rashes, weakness or pain in arms and legs, facial paralysis on one side, irregular heart beat, fever, stiff neck, headache, persistent malaise.
Not all people bitten by a deer tick will get Lyme disease. Less than 40% of all deer ticks carry the bacteria responsible for Lyme disease. However, an attached deer tick must be removed within 24 - 36 hours to prevent it from transmitting the bacteria, if it is infected.
Diagnosis and Treatment
Early diagnosis and treatment makes a difference. The early stages of Lyme disease are more effectively treated with antibiotics. See your physician immediately if you develop any Lyme disease symptoms following a deer tick bite or exposure to deer-tick infested areas regardless of your vaccination status.
If a person is not treated in the early stages of Lyme disease, these late symptoms may develop months or years after the tick bite: Chronic arthritis in one or more joints, usually the knees, neurologic impairment, fatigue.
Lyme Disease Vaccine
General Information
LYMErix is available to persons 15 through 70 years of age who have substantial exposure to deer ticks. These are people with frequent or prolonged exposure to deer ticks in areas endemic for Lyme disease. Those having exposure less than that (see below) may have inadequate benefit to warrant the risks and costs of the vaccine. Individuals who have had previous episodes of Lyme disease and have not changed their life style (i.e., hiking, camping and working outdoors) may wish to consider the vaccination series if they do not have persistent Lyme arthritis or other vaccine contraindications.
The LYMErix is not 100% protective against Lyme disease and provides no protection against Erlichosis or Babesiosis, two other diseases carried by infected deer ticks. Thus, individuals who are immunized with this vaccine must take the same tick precautions they would if they were not immunized (e.g., wear appropriate protective clothing, use tick (insect) repellents and do careful tick checks after being in potentially tick-infested areas). While ticks are hard to see, tick checks are very worthwhile. Lyme disease is not transmitted until the infected tick has been attached for at least 24 hours. Early diagnosis and treatment of Lyme disease also dramatically decreases the risk of later serious disease.
Vaccine Safety and Efficacy
The most common side effects are local injectionsite reactions including soreness, redness, and swelling. Less common side effects include flulike symptoms, fever and muscle aches (reported approximately 23% of vaccine recipients). The vaccine should be given with caution to individuals with arthritis, as there is some theoretical concern that in some cases it may worsen some forms of arthritis, and the issue has not yet been studied.
The vaccine is given on a 0, 1, 12 month schedule, and should be started in the spring for optimal effectiveness. While definitive data does not exist, boosters will likely be needed every year or two. Effectiveness after the first two doses (for the first tick season) is about 49%. Effectiveness for the second season after the third dose is about 76%, and 100% in preventing asymptomatic infections.
Defining Greatest Risk of Exposure to Lyme Disease
Persons with frequent or prolonged exposure in wooded, bushy or overgrown areas, (areas that are likely habitats for deer ticks, as well as deer and rodents hosts) are at greater risk of tick bites than those with minimal or lesser exposure. Such exposures may occur during either recreational or occupational activities.
Examples of when immunization with the Lyme vaccine would be appropriate:
1. People who have cabins in the endemic counties and who spend substantial time outside in wooded, bushy or overgrown grassy environments around their cabins during the tick season. (May-September)
2. People who frequently recreate (i.e., camping, canoeing, backpacking, fishing, hiking) in wooded, bushy or overgrown grassy environments in endemic counties.
3. People who live in rural areas of endemic counties and frequently work or recreate outdoors around their home.
4. People who work outdoors in wooded, bushy or overgrown grassy environments for frequent and prolonged periods of time in endemic areas.
Examples of when immunization with the Lyme vaccine would not be appropriate:
1. People living in developed, densely populated suburban areas such as Woodbury, Stillwater or other city neighborhoods without substantial and prolonged exposure to large wooded, bushy or overgrown grassy tracts of land.
2. People with cabins in endemic areas that only spend time in the cabin or on the lake, but who do not venture into the woods and infrequently work outside around the cabin.
3. Individuals who infrequently recreate (i.e., camping, canoeing, backpacking, fishing, hiking) in wooded, bushy or overgrown grassy environments in endemic counties.
4. Bicyclists who only bike on roads, tarred or graveled bike paths, regardless of the deer tick density in the area. (This would not include frequent off the road mountain biking in endemic areas.)
5. Persons younger than 15 years or older than 70 years (Currently, the vaccine is not licensed for these age groups.)
6. Pregnant women.
7. Persons with treatment-resistant Lyme disease arthritis.
Prevention and Tick Removal
The following actions can help reduce your chance of getting a tick-borne disease: Wear light colored clothing so ticks are more visible. Create a barrier to ticks by tucking pants into socks or boots or wear gaiters. Use insect repellent containing DEET, but carefully follow the directions on the container. After being in a deer-tick habitat, do a complete body check, shower and vigorously towel dry.
Remove attached ticks as soon as possible. Use a tweezers and grasp the tick as close to the mouth parts as possible. Not the body of the tick! Pull the tick out slowly to prevent breaking part of the tick off under the skin. Apply an antiseptic to the bite site. Watch for the rash and early symptoms of Lyme disease.
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