Symptoms
The disease has traditionally been divided into 3 stages, which, however, cannot be clearly distinguished from each other and do not require patients to pass through them obligatorily and sequentially. The staging has therefore been abandoned by some experts in favor of an early and late phase or organ-based classification. Borrelia initially infect the skin and can then spread to other organs within weeks to years. The immune response of the host also plays a role in the development of the disease. The course varies from self-limiting to years of chronic disease resistant to treatment. © Lucille Solomon, 2012 http://www.lucille-solomon.com Skin: Within approximately 3 to 30 days, a localized rash called erythema migrans, or wandering redness, develops. The clearly demarcated, non-pruritic and painless rash extends for days to weeks in a ring or area around the injection site and becomes progressively lighter in the center (similar to a fungal skin infection). The edge is slightly raised. The skin redness disappears on its own after weeks to months, but this does not equate to healing from the disease. It should be noted that the rash does not necessarily develop (!) In some patients it is accompanied by flu-like symptoms such as aching limbs, feeling sick, swelling of the lymph nodes, fever, headache and nausea. A benign Borrelia lymphocytoma may rarely develop on the skin. These are blue-red nodules that often appear on the ear, neck, nipples, armpits, scrotum, or dorsum of the foot. This skin reaction is most common in children. Skin atrophies, known as acrodermatitis chronica atrophicans, are also possible after years. Nervous system: An attack on the nervous system manifests itself, among other things, as meningitis, cerebral neuritis and neural neuritis. Musculoskeletal system: The muscles and large joints ache and symptoms of arthritis (Lyme arthritis) develop, possibly with involvement of the tendons and bursae. Less commonly, various other internal organs are affected, such as the heart (arrhythmias, AV block, inflammation), kidney, eyes, lungs, and liver.
Causes and transmission
Lyme disease is a bacterial infectious disease caused by the gram-negative, spiral-shaped bacterium sensu stricto and other borrelia, et al. , and , all of which are found in Europe. The term sensu lato is used as an umbrella term for these species (sensu stricto: in the narrow sense, sensu lato: in the broader sense). The spirochetes are transmitted to humans by ticks of the genus, mainly by , the wood tick. The reservoir is mammals such as mice, squirrels, foxes, hedgehogs, deer, birds and reptiles. The Borrelia live in the midgut of the ticks and only enter the saliva during the blood meal and on this way into the skin of the human. The risk of transmission during a tick bite increases with the duration of the bite. The tick must first suck for several hours before the bacterium is transmitted. Therefore, it is important to remove ticks as soon as possible.
Epidemiology
Lyme disease is the most common tick-borne disease in our latitudes. Because the greatest risk of a tick bite occurs from spring to fall, most acute infections are reported during this time. 5-30% (even up to 50% in high-risk areas) of ticks distributed in many countries carry the bacteria. The incidence in many countries is estimated at 115-155 per 100,000 population and is among the highest in Europe.
Diagnosis
Diagnosis is made under medical treatment primarily on the basis of the clinical presentation, patient history, and secondarily on laboratory chemistry techniques to support the hypothesis. The skin rash, although typical, does not occur in all patients (see above). Many patients do not remember a tick bite because it is painless. Possible differential diagnoses include skin diseases of other causes (e.g., erysipelas, allergic reactions to an insect bite), fungal infections, meningitis and encephalitis of other causes, Guillain-Barré syndrome (inflammation of the spinal nerve roots and peripheral nerves), B-cell lymphoma, and multiple sclerosis.
Drug treatment
Lyme disease is treated with antibiotics, including tetracyclines (doxycycline), beta-lactam antibiotics (amoxicillin, ceftriaxone, cefuroxime, cefotaxime), or macrolides (clarithromycin, azithromycin), depending on the stage and patient. For detailed guidelines, please refer to the scientific literature. Therapy is also subject to controversy. Antibiotic therapy should be started as early as possible to prevent the spread of the pathogen to other organs and to prevent chronic damage. Appropriate precautions must be observed. Tetracyclines are contraindicated in children under 9 years of age because of incorporation into the bones and teeth. Therefore, beta-lactams are predominantly used in this group. Tetracyclines should also not be administered during pregnancy and lactation. For symptomatic treatment, nonsteroidal anti-inflammatory drugs, local glucocorticoids, antirheumatic drugs, and other drugs may be indicated, depending on the severity.
Prevention
Secondary prophylaxis: The American Infectious Diseases Society (http://www.idsociety.org) recommends 200 mg doxycycline as a single dose for secondary prophylaxis after a tick bite if 4 criteria are met. In many countries, no such antibiotic prophylaxis is given because the benefit is not scientifically proven. Vaccination is not yet commercially available. In the USA, a vaccination was launched but withdrawn from the market. The best prevention is to avoid tick bites. Ticks are found in the undergrowth and on low-growing plants. They do not fall from trees and bushes, as is often assumed, but crawl to a suitable place after contact with the skin on the body. They are found in forests, parks and gardens. Closed shoes and long, smooth, light-colored pants should be worn when hiking or playing sports. It is easier to detect the ticks on light-colored materials. Socks should eventually be put over the pants. It is not aesthetically pleasing, but it can help prevent the disease. The undergrowth and roadsides should be avoided. After spending time in a risk area, the body should be checked for ticks and the ticks should be removed as soon as possible, within 24 hours. Ticks are mainly found in the armpit area, on the groin and the back of the knee, in children also on the face, neck and scalp. The date of the bite should be noted and the site observed for 30 days. Repellents, for example with the active ingredient diethyltoluamide (DEET), are used for chemical prevention.
