Lyme Disease| Lyme Disease Symptoms, Causes, Prevention & Treatment
Lyme Disease| Lyme Disease Symptoms, Causes, Prevention & Treatment
What is Lyme Disease?
Lyme disease, also known as Lyme borreliosis, is an infectious disease caused by a bacterium named Borrelia burgdorferi sensu lato found in and spread by ticks.
The tick becomes infected after feeding on infected deer or mice. The infection is spread to humans by a bite from an infected black-legged or deer tick.
Symptom of Lyme Disease
Just like hypertension, Lyme disease can affect multiple body systems and produce a broad range of symptoms.
It is important to note that not all patients with Lyme disease have all symptoms, and many of the symptoms are not specific to Lyme disease, but can occur with other diseases, as well.
The most common sign of lyme disease in the early stage is an expanding area of redness on the skin, known as erythema migrans, that appears at the site the tick bite about a week or two after the bite.
Lyme disease causes a rash, often in a bull’s-eye pattern, and flu-like symptoms. Joint pain and weakness in the limbs can occur as well.
In the second stage usually referred to as the early disseminated stage when the bacteria has started spreading throughout the body, symptoms such as chills, fever, enlarged lymph nodes, sore throat, vision changes, fatigue, muscle aches, headaches, will occur.
If still left untreated, the disease will get to the third stage referred to as late disseminated stage and this stage is characterized by severe headaches, arthritis of one or more large joints, disturbances in heart rhythm, brain disorders (encephalopathy) involving memory, mood, and sleep, short-term memory loss, difficulty concentrating, mental fogginess, problems following conversations, numbness in the arms, legs, hands, or feet.
The rash is typically neither itchy nor painful. If untreated, symptoms may include loss of the ability to move one or both sides of the face, joint pains, severe headaches with neck stiffness, or heart palpitations, among others. Months to years later, repeated episodes of joint pain and swelling may occur.
Occasionally, people develop shooting pains or tingling in their arms and legs. Despite appropriate treatment, about 10 to 20% of people develop joint pains, memory problems, and tiredness for at least six months.
Causes Of Lyme Disease
Lyme disease is caused by spirochetes, spiral bacteria from the genus Borrelia. Spirochetes are surrounded by peptidoglycan and flagella, along with an outer membrane similar to other Gram-negative bacteria. Because of their double-membrane envelope, Borrelia bacteria are often mistakenly described as Gram negative despite the considerable differences in their envelope components from Gram-negative bacteria.
The Lyme-related Borrelia species are collectively known as Borrelia burgdorferi sensu lato, and show a great deal of genetic diversity.
Prevention Of Lyme Disease
Below are some general tips on how to cover your body in order to prevent the tick from biting you;
- Put on protective clothing includes a hat, long-sleeved shirt, and long pants tucked into socks or boots.
- Go for light-colored clothing as it makes the tick more easily visible before it attaches itself
- Use special care in handling and allowing outdoor pets inside homes because they can bring ticks into the house
- People working in areas with woods, bushes, leaf litter, and tall grass are at risk of becoming infected with Lyme at work. Hence, adequate care must be taken when working.
- Work clothing used in risky areas should be washed in hot water and dried in a hot dryer to kill any ticks
- Permethrin sprayed on clothing kills ticks on contact, and is sold for this purpose. According to the CDC, only DEET is effective at repelling ticks
Lyme Disease Vaccination
In 1998, SmithKline Beecham developed a licensed product called LYMERix.
The product was a recombinant vaccine based on the outer surface protein A (ospA) of Borrelia burgdorferi bacteria. Prior to the licensure of LYMERix, a total of 18,047 doses of the vaccine was received by 6,478 people during clinical testing. The vaccine was found to confer protective immunity to Borrelia in 76% of adults and 100% of children with only mild or moderate and transient adverse effects.
Hundreds of vaccine recipients reported they had developed autoimmune and other side effects. Supported by some patient advocacy groups, a number of class-action lawsuits were filed against GlaxoSmithKline, alleging the vaccine had caused these health problems. These claims were investigated by the FDA and the Centers for Disease Control, which found no connection between the vaccine and the autoimmune complaints. Despite the lack of evidence that the complaints were caused by the vaccine, sales plummeted and LYMErix was withdrawn from the market. Between the time of its licensure in 1998 and July 31, 2000, about 1.5 million doses of the vaccine were distributed.
Currently, three Lyme disease vaccines are available. LymeVax, formulated by Fort Dodge Laboratories, contains intact dead spirochetes which expose the host to the organism. Galaxy Lyme, Intervet-Schering-Plough’s vaccine, targets proteins OspC and OspA. The OspC antibodies kill any of the bacteria that have not been killed by the OspA antibodies. Canine Recombinant Lyme, formulated by Merial, generates antibodies against the OspA protein so a tick feeding on a vaccinated dog draws in blood full of anti-OspA antibodies, which kill the spirochetes in the tick’s gut before they are transmitted to the dog
Lyme Disease Treatment
Treatment in the early stage of Lyme disease is quite effective. Patients can be treated with some antibiotics such as doxycycline, amoxicillin, or cefuroxime axetil. People with certain neurological or cardiac forms of illness may require intravenous treatment with antibiotics such as ceftriaxone or penicillin.
Treatment regimens listed in the following table are for localized (early) Lyme disease. See references
|Age Category||Drug||Dosage||Maximum||Duration, Days|
|Adults||Doxycycline||100 mg, twice per day orally||N/A||10-21*|
|Cefuroxime axetil||500 mg, twice per day orally||N/A||14-21|
|Amoxicillin||500 mg, three times per day orally||N/A||14-21|
|Children||Amoxicillin||50 mg/kg per day orally, divided into 3 doses||500 mg per dose||14-21|
|Doxycycline||4 mg/kg per day orally, divided into 2 doses||100 mg per dose||10-21*|
|Cefuroxime axetil||30 mg/kg per day orally, divided into 2 doses||500 mg per dose||14-21|
*Recent publications suggest the efficacy of shorter courses of treatment for early Lyme disease.
Lyme Disease Prevalence
In northern Africa, B. burgdorferi sensu lato has been identified in Morocco, Algeria, Egypt and Tunisia. In East Africa, two cases of Lyme disease have been reported in Kenya.
In Asia, ticks are being found more frequently in Japan, as well as in northwest China, Nepal, Thailand and far eastern Russia. Borrelia has also been isolated in Mongolia.
In Europe, B. burgdorferi sensu lato-infected ticks are found predominantly in central Europe, particularly in Slovenia and Austria, but have been isolated in almost every country on the continent.Incidence in southern Europe, such as Italy and Portugal, is much lower
Some cases have also been reported in Canada, Mexico, U.S.A, Brazil, Columbia, Bolivia.