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| Lyme Disease Facts - What is it and Where did it come from? |
Definition of Lyme Disease – Lyme disease is a bacterial infection caused by the cork-screw shaped bacterium, Borrelia burgdorferi, and is primarily transmitted through the bite of an infected tick. How the disease is spread – Small mammals such as the mice, voles, chipmunks, and large mammals such as the white tailed deer are hosts to the Ixodes scapularis (black-legged tick) and Lone star tick. Over 49 species of migrating birds have been found to carry these ticks. Borrelia strains – Since 1982 over 100 U.S. and 300 worldwide strains of the bacterium have been discovered. Borrelia Burgdorferi - The causative agent, Borrelia burgdorferi, is a type of spirocheteal bacteria. Other spirochetes include the causative agents of syphilis, and relapsing fever. Spirochetes are long, thin, spiral-shaped bacteria. About 100,000 of “Bb” laid side to side would equal one inch. The bacterium is able to move around the body through the bloodstream and between tissue. It can also invade tissue, replicate, and leave the cell - destroying the cell as it emerges. Sometimes, as the bacterium emerges, the cell wall collapses around the bacterium, forming a "cloaking device". This action may aid the bacteria's ability to hide from the immune system response. The bacteria can also change into a spheroplast or “L” form as well as a cyst stage, thus unaffected by common antibiotics. Many Lyme patients have co-infections with babesia, ehrlichia, and/or HHV-6, a herpes virus, which makes treatment much more challenging. Lyme disease history - It is a popular misconception that Lyme disease was discovered in the late 1970's in Lyme, Connecticut, but 100+ year old laboratory mice specimens have been found infected with this bacterium. In the early 1980's, an entomologist at the U.S. Rocky Mountain Lab., of the National Institutes of Health by the name of Willy Burgdorfer, MD, Ph.D., was investigating outbreaks of Rocky Mountain spotted fever. He undertook a very close inspection of the tick--and found poorly stained, sluggish spirochetes. Within a year, the spirochetes had been named Borrelia burgdorferi (Bb), in his honor, and definitely identified as the causative agent of Lyme disease. |
| Ticks, Their Behavior, Life Cycle and Habitat |
Rash - Lyme disease is called the Great Imitator because it can mimic many other diseases, such as MS, Fibromyalgia, Chronic Fatigue, and Rheumatoid Arthritis, which makes diagnosis difficult. A rash can appear several days after infection, or not at all. It can last a few hours or up to several weeks. The rash can be very small or very large (up to twelve inches across). A bulls-eye rash is the hallmark of LD. It is a round ring with central clearing. Unfortunately, this is not the only rash associated with Lyme. Various other rashes associated with LD have been reported. One bite can cause multiple rashes. The rash can mimic such skin problems as hives, eczema, sunburn, poison ivy, flea bites, etc. The rash can itch or feel hot or may not be felt at all. The rash can disappear and return several weeks later. For those with dark skin the rash will look like a bruise. If you notice a rash, take a picture of it. Some physicians require evidence of a rash before prescribing treatment. The bulls-eye rash occurs only 50% of the time. Other Early symptoms - Fever, muscle and joint aches, fatigue, sore throat,swollen glands, flu like aches, stiff neck, light sensitivity |
| Diagnosis, Laboratory Tests and Treatment |
Diagnosis - There is no test that can determine if a patient is infected with the LD bacterium and then demonstrates that the patient has become bacterium-free. Therefore, LD is a clinical diagnosis, based on signs and symptoms, with the patients travel history to endemic areas and test results being additional pieces of information in the complete picture. No test can "rule-out" Lyme disease. Laboratory tests - see Tests and Treatment page for more information. Treatment - Antimicrobial therapy is the foundation of Lyme disease management. Oral therapy with doxycycline or amoxicillin is appropriate for cases of early Lyme disease without neurologic involvement. Parenteral therapy with ceftriaxone should be reserved for patients with neurologic involvement, severe arthritis, or any life-threatening manifestation of Lyme disease such as complete heart block. Controversy surrounds the issue of patients with persisting signs and symptoms of the disease that results in chronic neurologic or rheumatologic disability. Several explanations have been proposed for residual symptoms in some patients: continued infection, immunologic disease, permanent tissue damage resulting from the initial infection, or coinfection with another tick- borne pathogen. Oral antimicrobial therapy is effective and appropriate for most patients. Intravenous therapy is reserved for more serious disseminated cases. For more information, see our Tests and Treatment page |
| Protection and Prevention |
Protection and prevention - The use of sprays is a personal decision so you must know the facts. Products that contain DEET are tick repellents. They do not kill the tick and are not 100% effective in discouraging a tick from feeding on you. Products like Permanone contain premethrin, and are known to kill ticks. However, they are not to be sprayed on the skin. Permanone can be sprayed on clothing. Once it is dry it is assumed to be safe. Ticks are anti-gravitational. They are generally seeking the highest point. If they get on your body below the clothes line, one hopes they will travel up and die once they come in contact with treated clothing. Note: If the tick meets resistance on its journey to the top of your head it will stop and feed at that point. If you are wearing shorts and the tick gets stuck in the bend behind your knee the Permanone will not be helpful. Vaccine – SmithKline Beecham created a Lyme vaccine in 2001. But, lawsuits were filed which stated it caused arthritis and other autoimmune disorders. Due to these complaints and lack of public interest pulled it off the market in March, 2002. Property Protection - Consult with a professional about using insecticides on your property to kill ticks. Eliminate tall grass especially near a forest edge on your property. Provide a stone barrier between tick habitat and your yard. Pets and Other Animal Protection -Lyme disease has been diagnosed in humans, dogs, cats, horses, goats, and cattle. Other species may also be at risk. Lyme disease can affect individual pets differently. Some animals may display no symptoms. Other animals may develop fever, loss of appetite, painful joints, lethargy, and vomiting. If left untreated, the spirochete may damage the eyes, heart, kidneys, and nervous system. Cats may show lameness, fever, loss of appetite, fatigue, eye damage, unusual breathing, or heart involvement. Many infected cats do not show noticeable symptoms.Infected dogs may be lethargic, have a poor/loss of appetite, or a fever. Dogs may also experience lameness shifting from one joint to another, fatigue, kidney damage or failure, heart disorders, or neurologic involvement (e.g. aggression, confusion, overeating, and seizures). Dogs can be infected with the Lyme bacterium but not exhibit any noticeable symptoms. Dogs appear to have the same expression of disease as humans; therefore, humans have been considered an animal model for dogs. Transplacental transmission has occurred in dogs. Treat pets with proper repellents. Do a thorough tick check on your pet before it comes indoors. Save the tick in the refrigerator in a sealed container. Keep infected animals away from children to reduce chance of their exposure through saliva, urine, etc. |
| DISEASE AND TICK FACTS |
Several kinds of ticks in Iowa can be infected with the bacteria: Ixodes scapularis (Black-legged tick, formerly called deer tick) Dermacentor (Dog or wood tick) Amblyoma americana (Lone Star tick) In the past, only the black-legged (deer) tick was proven capable of transmitting the bacteria to humans. Current research has now proven the Lone star and the dog (wood) tick are able to transfer this borrelia bacteria to humans and dogs. In April, 2004, the wood tick was documented as the vector of a Lyme like disease in Montana. Currently, health officials are not passing this information to the public. The widespread distribution of these tick vectors greatly increases the prevalence of Boreliosis. In the past, only Ixodes ticks (deer ticks) collected by the public were saved for Lyme disease research at Iowa State University. The public needs to understand the potential danger of all tick bites, not only that from the deer tick. A research study is underway in Missouri which will give more answers in the next few years. The Black legged tick has a 2 year life cycle and must feed 3 times. In the larvae stage, it is tan, the size of a pinhead, and feeds on small animals like the mouse where it can pick up the spirochete. During the nymph stage the tick is the size of a poppy seed, beige or partially transparent and feeds on larger animals such as cats, dogs and humans. The adult ticks are black and/or reddish and feed on cattle, deer, dogs and humans. The Lone Star tick is grey with a white dot. Multiple diseases can be contracted from a single tick bite. Ticks are bloodsucking external parasites that feed on humans, wild and domestic mammals, reptiles and others. The black- legged tick has been found on 49 species of migrating birds, which are helping to spread the bacteria into uninfected areas. Ticks are totally dependent on the blood/tissue fluids of the host. The longer an infective tick feeds, the greater the chance of infection. Ticks are not insects. Ticks have eight legs as an adult and two body segments, whereas insects have six legs as an adult and three body segments. Ticks are arachnids, as are chiggers, spiders and mites. Tick life cycle – Ticks have four life stages: egg, larva, nymph, and adult. The egg hatches into a larva. A larva ("seed" tick) has six legs. It feeds and molts into a nymph. A nymph has eight legs and no sex differentiation. It then feeds and molts into an adult. The adult is differentiated into male or female. The female requires a blood meal in order to lay eggs. A hard tick seeks a blood meal at, or slightly above, ground level by climbing onto vegetation and using its forelegs to feel/grab for a host. Ticks are usually found from ground level to three feet above the ground. A tick uses carbon dioxide, scent, body heat, and other stimuli to find a host. Other vectors and transmission – Mosquitoes, biting flies, and fleas have also been carriers of this bacterium. There are documented cases of Lyme disease contracted from an infected pet. The bacterium can be passed from an infected Mother to a child during pregnancy. Congenital outcomes can be miscarriage, neurological disabilities, or other major organs affected. |
| Rash and Other Early Symptoms |
