Borrelia
General Characteristics of genus Borrelia
• under the family spirochaetaceae• spiral-shaped / coiled but fewer coils than leptospira(3-10
loose coils)• have a length of 20-30um but a width of only 0.2-0.3um• motile with both rotational and translational movements• stains well with Giemsa stain• obligate aerobes or microaerophilic(grown in vitro)• has periplasmic flagella that determines the shape of the
bacteria.
http://www.cdc.gov/ncidod/dvbid/lyme/ld_Borreliaburgdorferi.htm
General Characteristics of genus Borrelia
• Culture Medium: Barbour-Stoenner-Kelly (BSK) medium• Its optimal growth temperature is 34° to 37°C, and the
organism has a generation time of 11 to 12 hours at 35°C• Viewed through Dark-Field Microscopy
http://en.wikipedia.org/wiki/File:Borrelia_burgdorferi_(CDC-PHIL_-6631)_lores.jpg
Virulence Factors
• Antigenic Variation• Outer Surface Proteins – OspA– OspC– Dbp(Decorin-binding protein)– Erps(Osp E/F-related proteins) and
CRASPs(Complement acquiring surface proteins)– cp32
Diseases Caused by Borrelia species
• LYME DISEASE - inflammatory disease caused by a spirochete that is transmitted by ticks, usually characterized initially by a rash followed by flulike symptoms including fever, joint pain, and headache.
– Caused by: Borrelia burgdorferi, Borrelia afzelii and Borrelia garnii(COLLECTIVELY CALLED: Borrelia burgdorferi sensu lato)
LYME DISEASE
• Symptoms of LYME DISEASE– Fever– Headache– Myalgia– Drowsiness – and the following stages......
LYME DISEASE
• Stages of LYME DISEASE– First stage- The rash caused by a tick’s bite has a
characteristic “bull’s eye” appearance, called Erythema Migrans.
http://www.medicinenet.com/black_widow_brown_recluse_pictures_slideshow/article.htm
LYME DISEASE
• Stages of LYME DISEASE– Second stage- starts weeks to months after
infection and may cause arthritis, neurologic disorders, and carditis
– Third stage- characterized by chronic arthritis
LYME DISEASE
• Transmitted by:– Reservoir Host: rodents/ white-footed mouse– Arthropod vector: Ixodes scapularis (deer ticks, all stages can harbor
the spirochete and transmit disease)- Needs around 24 hours(period of attachment before transmitting of disease).
mouse deer tick
Engorged(infected) tick
LYME DISEASE
• LABORATORY DIAGNOSIS• Specimen used: Blood, biopsy specimen, joint and
cerebrospinal fluid
• TREATMENT:• Doxycycline, amoxicillin, parenteral and broad spectrum
cephalosporins
• VACCINE• LYMErix vaccine
Diseases Caused by Borrelia species
• RELAPSING FEVER– an acute febrile illness caused by Borrelia
recurrentis
– The high fevers of presenting patients spontaneously abate and then recur
Diseases Caused by Borrelia species
• RELAPSING FEVER• Vector: Pediculus humanus (sucking louse)
• B. recurrentis infects the person via either abraded or intact skin (or mucous membranes) and then invades the bloodstream.
Soft-bodied licehttp://emedicine.medscape.com/article/787000-overview
Diseases Caused by Borrelia species
• RELAPSING FEVER• Symptoms: rapid pulse,
headache,weakness,anorexia, weight loss, cough
• Relapses: – primary febrile episode typically ends after 3-6 days – the first relapse occurs abruptly 7-10days later– relapses average to 3, and there can be more than 10
Epidemiology
• LYME DISEASE– Of the total Lyme Disease reports in the world in
2006, 59,770 cases or 93% of it came from 10 states in the US (Connecticut, Delaware, Maryland, Massachusetts, Minnesota, New Jersey, New York, Pennsylvania, Rhode Island and Wisconsin. )
• RELAPSING FEVER– prevalent in Ethiopia and Sudan
Laboratory Diagnosis
• SPECIMEN COLLECTION– Sp of choice: Blood or CSF– Examination of live ticks: The midgut of each tick is to be dissected
Laboratory Diagnosis
• MIROSCOPIC EXAMINATION– the midgut of each tick was removed under a
stereomicroscope and homogenized in a 0.9% NaCl
Laboratory Diagnosis
• ANTIBIOTIC SUSCEPTIBILITY– Oral: doxycycline, amoxicillin, clarithromycin– Injection: benzylpenicillin, cefotaxime
and ceftriaxone– Vaccines: LYMErix vaccine
http://www.medicinenet.com/black_widow_brown_recluse_pictures_slideshow/article.htm
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