Microbiology
Summary
Borrelia burgdorferi is a spiral-shaped bacteria that causes Lyme disease. Lyme disease is commonly transmitted by ticks, particularly the Ixodes scapularis tick , which relies on white-tailed deer and small mammals such as the white-footed mouse for its life cycle. B. burgdorferi is primarily endemic to the Northeastern United States, although it's becoming more prevalent in other US regions. This bacterium can be visualized under a microscope using two stains: Wright's stain and the Giemsa stain.
Lyme disease progresses through three stages. These stages incorporate a range of symptoms, including the characteristic bull's eye rash (erythema chronicum migrans), flu-like symptoms, heart block caused by myocarditis, bilateral Bell's palsy, and in the final stage, migratory polyarthritis and cognitive issues. Treatment for Lyme disease ideally begins at the earliest stage with antibiotics such as doxycycline and ceftriaxone for severe cases.
Lesson Outline
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FAQs
Borrelia burgdorferi is a bacteria specifically known for causing Lyme disease. It is typically transmitted to humans through bites of Ixodes scapularis ticks. The bacteria cause a series of symptoms, which, collectively, are referred to as Lyme disease.
The major vector for the transmission of Borrelia burgdorferi to humans is the Ixodes scapularis or the black-legged tick. These ticks get infected by feeding on infected reservoir host, usually small mammals. When an infected tick bites a human and remains attached for at least 36-48 hours, it can transmit the bacteria, leading to Lyme disease.
The early symptoms of Lyme disease include fatigue, chills, fever, headache, muscle and joint aches, and swollen lymph nodes. Most notably, one of the hallmarks of Lyme disease is a rash called erythema chronicum migrans, often described as a "bull's eye rash". It begins at the site of the tick bite after a delay of 3-30 days and gradually expands over several days.
The later stages of Lyme disease are often associated with more serious complications including migratory polyarthritis and neurological conditions such as heart block and Bell's palsy. Migratory polyarthritis is characterized by joint pain and swelling, while Bell's palsy is a condition that causes temporary paralysis of the facial muscles, and heart block involves impaired heart function.
The common antibiotics used for treating Lyme disease caused by B. burgdorferi are doxycycline and ceftriaxone. Doxycycline is generally used for early-stage Lyme disease, while ceftriaxone is employed for treating severe cases of Lyme disease such as those affecting the nervous system. Both these drugs help in eliminating the B. burgdorferi bacteria from the body.
