1. Borrelia and Leptospira are spirochete bacteria that can cause relapsing fever and Lyme disease. 2. Borrelia is transmitted by ticks and body lice and causes relapsing fever, characterized by recurring fevers. Leptospira is transmitted by contact with contaminated water and causes Weil's disease, affecting the liver and kidneys. 3. Diagnosis involves microscopic examination of blood or urine to detect the spirochetes or serological tests to detect antibodies. Treatment includes antibiotics like doxycycline, penicillin, and tetracycline.

1. Borrelia and Leptospira
Dr. Himanshu Khatri
Email: himanshubkhatri@yahoo.co.in

2. Spirochetes
• Speira= coil, and chaite=hair
• Elongated
• Motile (by endoflagella located between cell
wall and outer membrane)
• Flexible
• Spirally twisted along long axis

3. Spirochetes
• Three species:
1. Treponema
2. Borrelia
3. Leptospira

4. Borrelia
• They are large spirochetes
• Several species occur as commensals on
buccal and genital mucosa

5. Morphology
• It is an irregular spiral (unlike Treponema
which is a regular spiral)
• It possess 5-10 loose coils

6. • Borrelia cause:
• 1. Relapsing fever
• 2. Fusospirochetosis by B. vincenti
• 3. Lyme disease by B. burgdorferi

7. Relapsing fever (RF)
• It occurs in epidemic and
sporadic form
• It is an arthropod borne
infection
• RF is of two types: tick
borne and louse borne
• The borrelia which cause
these two types are
indistinguishable in
morphology and many
other features
Louse

8. Louseborne RF
• It is transmitted from person to person
through body lice (Pediculus humanus
corporis)
• Humans are the only reservoir
• It is caused by B. recurrentis
• It gives a more severe infection with high case
fatality

9. Tickborne RF
• It is transmitted through ticks
• It is caused by B. duttonii, B. hermsii, B. parkeri
etc
• Several soft ticks belonging to the species
Ornithodorus act as vectors
• It is a zoonosis
• It gives a milder form of illness with lesser case
fatality
• However, relapses of fever are more frequent

10. Antigenic properties
• DNA rearrangements occur in DNA plasmids of
borrelia
• These rearrangments cause antigenic variations
in vivo
• This is how borrelia escape the immune system
• It is also believed to be the reason for recurrence
of fever
• When immunity is developed to all antigens,
recovery of disease occurs

11. Pathogenicity and clinical features
• First symptom is sudden onset fever
• During this period of 3-5 days, borrelia are abundant in
patient’s blood
• The immune system clears the borrelia from the blood
• This results in an afebrile period which lasts 4-10 days
• During this period, antigenic variation takes place
• The borrelia escape the immune system and multiply
• Their numbers again increase in blood, and fever
reoccurs
• The disease ultimately subsides after 3-10 relapses

12. RF as a cause of Pyrexia of Unknown
Origin (PUO)

13. Laboratory diagnosis
• Borrelia can be
demonstrated in blood
• A drop of blood may be
examined under a dark
ground or phase contrast
microscope
• They are present only in
pyrexial period
• Borrelia have a
characteristic ‘lashing’
motility
• Blood smears can be
stained with Giemsa or
Leishman stain

14. Laboratory diagnosis…cont’d
• Cultivation of borreliae is too difficult
• Serological diagnosis is impractical due to
antigenic variation

15. Prophylaxis
1. Louse borne relapsing fever:
• Prevention of louse infestation
• Use of insecticides
2. Tick borne relapsing fever:
• It is difficult
• It includes identification of tick infested
places eradication of vectors

16. Treatment
• Tetracycline, chloramphenicol, penicillin and
erythromycin are effective

17. Borrelia vincenti
• It is a normal commensal in mouth
• But in opportunistic conditions, it may cause ulcerative
gingivostomatitis
• It may also cause ulcerative oropharyngitis (Vincent’s
angina)
• The predisposing conditions include malnutrition and
viral fevers
• In Vincent’s angina, B. vincenti is always associated
with fusiform bacilli (Fusobacterium fusiforme)
• The symbiotic infection is called ‘fusospirochetosis’

18. Laboratory diagnosis
• Stained smears from
the exudates of the
lesions show borrelia
along with fusiform
bacilli

19. Treatment
• Penicillin and metronidazole are used

20. Lyme disease: Borrelia burgdorferi
• It is called Lyme disease as it was first
observed in Lyme, Connecticut, USA
• It is transmitted by bites of hard ticks like
Ixodid ticks
• The natural hosts are deer, rodents and other
animals

21. Clinical features
• Lyme disease occurs in
three stages:
• The first stage is localized
infection
• It appears as an
expanding annular skin
lesion
• It is called ‘erythema
migrans’

22. Lyme disease…2nd stage
• The second is that of ‘disseminated infection’
• It appear a few weeks later
• Patient develops fever, headache, myalgia,
arthralgia and lymadenopathy
• Some develop meningeal or cardiac
involvement

23. Lyme disease…3rd stage
• The third stage is ‘persistent infection’
• It sets in months or years later
• It occurs as chronic arthritis, polyneuropathy,
encephalopathy and acrodermatitis chronica
atrophicans

24. Laboratory diagnosis
• It can be made by culture or by serology
• Borrelia grow slowly culture is time
consuming not the preferred method
• Also, serology is more practical as there is no
antigenic variation
• Serology is positive only after 1-2 months of
illness

25. Treatment
• Doxycycline, amoxicillin and cefuroxime

26. Leptospira
• They are delicate
spirochetes (they are
thinner than Treponema
and Borrelia)
• Lepto means fine or thin
• They have hooked ends
• They are better stained
with silver impregnation
methods

27. • Several leptospira are saprophytic
• But many are parasitic in rodents and other
animals
• Humans are infected with leptospires when
contaminated water with urine of carrier
animals enters through cuts or abrasions on
the skin, or through intact mucosal surfaces

28. Clinical features
• The clinical picture ranges from mild
undifferentiated fever ( around 90%) to Weil’s
disease (around 10%)
• In Weil’s disease, liver and kidneys are
damaged
• Weil’s disease is usually caused by the
serogroup L. Icterohemorragiae

29. Weil’s disease
• Jaundice occurs by the 2nd or 3rd day
• The synthesis of coagulation factors is
hampered
• Thus, purpuric hemorrhages may be seen on
the skin or mucosa
• And hence the name icterohemorrhagiae is
given to the serogroup causing it
• The kidneys are usually involved and
albuminuria is a constant feature

31. • Leptospira are seen in the blood in the acute
phase of the disease (leptospiremic phase)
• They can be rarely seen after 8-10 days
• But they continue to persist in the internal
organs
• They are most abundant in the kidneys
• So, they can be demonstrated in urine in the
latter stages of the disease (leptospiruric
phase)

32. Laboratory diagnosis
• It includes:
1. demonstration of leptospira
by dark field microscopy in
blood (usually in the 1st
week) and urine (2-6 weeks)
2. isolation in culture (rarely
done)
3. inoculation in guinea pigs
(rarely done)
4. serological tests (during 2-4
weeks of illness) most
common. Even rapid kits
for IgM and IgG are
available

33. Prophylaxis
• Rodent control
• Disinfection of water
• Wearing of protective clothing

34. Treatment and chemoprophylaxis
• Penicillin and tetracycline
• A mild Jarisch-Herxheimer reaction may occur
in some
• Doxycycline can be given for prophylaxis

35. THANK YOU