Leptospirosis is a zoonotic bacterial infection caused by Leptospira interrogans, which has over 200 serovars. It is transmitted to humans via contact with infected animal urine and can cause a range of symptoms from mild to severe. Early diagnosis is important as antibiotic treatment is most effective in the early stages of the disease. Laboratory diagnosis involves culturing blood and urine to detect the bacteria, as well as serological tests to detect the antibody response to infection.

1. Leptospirosis
Leptospirosis
Dr.T.V.Rao MD
Dr.T.V.Rao MD

2. Leptospirosis - Zoonosis
Leptospirosis - Zoonosis
Leptospirosis is an acute anthropo-zoonotic
Leptospirosis is an acute anthropo-zoonotic
infection of worldwide significance caused by
infection of worldwide significance caused by
spirochaete Leptospira interrogans which has 23
spirochaete Leptospira interrogans which has 23
serogroups and >200 serovars. Various factors
serogroups and >200 serovars. Various factors
influencing the animal activity, suitability of the
influencing the animal activity, suitability of the
environment for the survival of the organism and
environment for the survival of the organism and
behavioral and occupational habits of human
behavioral and occupational habits of human
beings can be the determinants of incidence and
beings can be the determinants of incidence and
prevalence of the disease.
prevalence of the disease.

3. What is leptospirosis?
What is leptospirosis?
Leptospirosis, also known as canicola fever,
Leptospirosis, also known as canicola fever,
hemorrhagic jaundice, infectious jaundice, mud
hemorrhagic jaundice, infectious jaundice, mud
fever, spirochetal jaundice, swamp fever,
fever, spirochetal jaundice, swamp fever,
swineherd's disease, caver's flu or sewerman's
swineherd's disease, caver's flu or sewerman's
flu, is a bacterial infection resulting from
flu, is a bacterial infection resulting from
exposure to the
exposure to the Leptospira interrogans
Leptospira interrogans
bacterium. There is an acute form of human
bacterium. There is an acute form of human
infection known as Weil's disease, where the
infection known as Weil's disease, where the
patient suffers from jaundice, though this term is
patient suffers from jaundice, though this term is
often (incorrectly) used to describe any case of
often (incorrectly) used to describe any case of
infection..
infection..

4. Leptospirosis – A Major Zoonotic
Leptospirosis – A Major Zoonotic
Infection
Infection
Weil's disease is comparatively rare,
Weil's disease is comparatively rare,
though 'mild' cases of leptospirosis
though 'mild' cases of leptospirosis
happen everywhere there are carriers,
happen everywhere there are carriers,
and it is believed that leptospirosis is one
and it is believed that leptospirosis is one
of the most common zoonotic infections in
of the most common zoonotic infections in
the world. Millions of people are infected
the world. Millions of people are infected
each year, but information and treatment
each year, but information and treatment
can be limited, especially in the developed
can be limited, especially in the developed
world where cases are considered 'rare'
world where cases are considered 'rare'
by the medical community.
by the medical community.

5. Animals spread Leptospirosis
Animals spread Leptospirosis
Rats, Mice, Wild Rodents,
Rats, Mice, Wild Rodents,
Dogs, Swine, Cattle are
Dogs, Swine, Cattle are
principle source of
principle source of
infection
infection
The above animals excrete
The above animals excrete
Leptospira both in active
Leptospira both in active
infection and
infection and
Asymptomatic stage
Asymptomatic stage
The Leptospira survive and
The Leptospira survive and
remain viable for several
remain viable for several
weeks in stagnant water.
weeks in stagnant water.

6. What causes Leptospirosis
What causes Leptospirosis
Leptospirosis is a bacterial disease that
Leptospirosis is a bacterial disease that
affects humans and animals. Leptospira
affects humans and animals. Leptospira
bacteria are found worldwide and there
bacteria are found worldwide and there
are many different types or serovars
are many different types or serovars
capable of causing disease. Disease
capable of causing disease. Disease
caused by Leptospira bacteria is most
caused by Leptospira bacteria is most
common in temperate or tropical climates
common in temperate or tropical climates
and appears to be rare in North America.
and appears to be rare in North America.

7. Scientific Beginning
Scientific Beginning
It was first described by
It was first described by Adolf Weil
Adolf Weil in
in 1886
1886
when he reported an "acute infectious
when he reported an "acute infectious
disease with
disease with enlargement of spleen
enlargement of spleen,
,
jaundice
jaundice and
and nephritis
nephritis".
". Leptospira
Leptospira was
was
first observed in
first observed in 1907
1907 from a
from a post mortem
post mortem
renal tissue
renal tissue slice.
slice.[2]
[2]

8. Pathogenic strains x Non pathogenic
Pathogenic strains x Non pathogenic
Leptospirosis
Leptospirosis
There are several species of Leptospira only few
There are several species of Leptospira only few
are pathogenic to Humans, rest to some Animals
are pathogenic to Humans, rest to some Animals
and Many in Nature as saprophytes
and Many in Nature as saprophytes
Leptospira Interrogans is Pathogenic there are
Leptospira Interrogans is Pathogenic there are
200 serovars.
200 serovars.
Leptospira biflexa Non Pathogenic there are 60
Leptospira biflexa Non Pathogenic there are 60
serovars
serovars
Further classifications are made on shared
Further classifications are made on shared
antigens
antigens

9. Genomic based classification
Genomic based classification
DNA – DNA hybridization studies proved
DNA – DNA hybridization studies proved
more specific
more specific
The traditional serologic classification has
The traditional serologic classification has
limitations at Molecular level, but useful at
limitations at Molecular level, but useful at
Epidemiological studies.
Epidemiological studies.

10. Morphology
Morphology
The Leptospira appear
The Leptospira appear
tighly coiled thin flexible
tighly coiled thin flexible
Spritochetes 5 – 15
Spritochetes 5 – 15
microns long.
microns long.
Fine spiral of 0.1 – 0.2
Fine spiral of 0.1 – 0.2
microns
microns
One end appears bent
One end appears bent
forms a hook.
forms a hook.
Actively motile
Actively motile
Seen best with dark field
Seen best with dark field
Microscopy.
Microscopy.

11. Greater Understanding with
Greater Understanding with
Electron Microscopy
Electron Microscopy
Electron Microscopy
Electron Microscopy
show thin axial
show thin axial
filament and a
filament and a
delicate membrane
delicate membrane
In dark field it may
In dark field it may
appear as chain of
appear as chain of
miniature cocci.
miniature cocci.

12. Comparative Morphology of
Comparative Morphology of
Spritochetes
Spritochetes

13. Culturing of Leptospira
Culturing of Leptospira
Leptospira grwos best
Leptospira grwos best
under aerobic conditions
under aerobic conditions
at 28
at 280
0
to 30
to 300
0
c best
c best
demonostrated in
demonostrated in
Semisolid agar media
Semisolid agar media
Optimal Media
Optimal Media
Fletchers Media
Fletchers Media
Stuarts Media
Stuarts Media
Optimal growth after 1 – 2
Optimal growth after 1 – 2
weeks
weeks

14. Growth requirements
Growth requirements
Leptospira derive
Leptospira derive
energy from oxidation
energy from oxidation
of long chain fatty
of long chain fatty
acids, and cannot use
acids, and cannot use
or carbohydrates or
or carbohydrates or
amino acids as major
amino acids as major
energy source.
energy source.

15. Antigenic structure
Antigenic structure
All isolates of L.inttterogans from different parts
All isolates of L.inttterogans from different parts
of the world are serologically related and exhibit
of the world are serologically related and exhibit
cross reactions in serologic tests.
cross reactions in serologic tests.
Overlapping of Antigens do occur in different
Overlapping of Antigens do occur in different
species.
species.
Outer envelop contains large amount of
Outer envelop contains large amount of
Lipopolysaccharides ( LPS )
Lipopolysaccharides ( LPS )
Antigenic structure varies from one strain to
Antigenic structure varies from one strain to
other
other
This variation forms the basis of serologic
This variation forms the basis of serologic
classification
classification

16. Genome of Leptospira
Genome of Leptospira
L. interrogans serogroup Icterhaemorrhagiae
L. interrogans serogroup Icterhaemorrhagiae
consists of a 4.33 megabase large chromosome
consists of a 4.33 megabase large chromosome
and a 359 kilobase small chromosome, totaling
and a 359 kilobase small chromosome, totaling
4,768 predicted genes. A series of genes have
4,768 predicted genes. A series of genes have
been discovered that could potentially be related
been discovered that could potentially be related
to adhesion. This genome differs from the two
to adhesion. This genome differs from the two
other pathogenic spirochaete (
other pathogenic spirochaete (Treponema
Treponema
palladium and Borrelia burgdorferi
palladium and Borrelia burgdorferi), though
), though
some similar genes are visible (CHGC, 2004).
some similar genes are visible (CHGC, 2004).

17. Pathogenesis
Pathogenesis
Leptospira are present in the water bodies
Leptospira are present in the water bodies
Enter through breaks in the skin ( cuts and
Enter through breaks in the skin ( cuts and
abrasions ) and mucous membranes
abrasions ) and mucous membranes
Enters through Mouth – Nose – Conjunctive
Enters through Mouth – Nose – Conjunctive
Rarely enters though ingestion.
Rarely enters though ingestion.
Incubation period 1 – 2 weeks
Incubation period 1 – 2 weeks
When multiples blood stream produces fever.
When multiples blood stream produces fever.
May establish organ involvement in Kidney and
May establish organ involvement in Kidney and
Liver,
Liver,
May produce hemorrhage and necrosis in the
May produce hemorrhage and necrosis in the
tissues and initiates dysfunction of these organs
tissues and initiates dysfunction of these organs

18. Sequence of Leptospira Infection
Sequence of Leptospira Infection

19. May present with
May present with
Jaundice
Jaundice
Hemorrhage
Hemorrhage
Nitrogen retention
Nitrogen retention
The Illness is Biphasic with initial temperature
The Illness is Biphasic with initial temperature
when the second phase comes with raise of IgM
when the second phase comes with raise of IgM
titers raise
titers raise
Aseptic meingitis – initial headache, stiffness of
Aseptic meingitis – initial headache, stiffness of
neck, pleocytosis of Cerebro spinal fluid
neck, pleocytosis of Cerebro spinal fluid

20. Presenting with Jaundice is
Presenting with Jaundice is
significant and Important,
significant and Important,
Serious Manifestation
Serious Manifestation

21. May present with Major
May present with Major
Complications
Complications
Nephritis
Nephritis
Hepatitis.
Hepatitis.
Manifestations in eye
Manifestations in eye
Muscular lesions
Muscular lesions
Many infections are
Many infections are
mild and subclinical
mild and subclinical

22. Weil’s Syndrome
Weil’s Syndrome
Weil's syndrome
Weil's syndrome is a severe form of
is a severe form of
leptospirosis that causes a continuous fever,
leptospirosis that causes a continuous fever,
stupor, and a reduction in the blood's ability to
stupor, and a reduction in the blood's ability to
clot, which leads to bleeding within tissues.
clot, which leads to bleeding within tissues.
Blood tests reveal anemia. By the third to sixth
Blood tests reveal anemia. By the third to sixth
day, signs of kidney damage and liver injury
day, signs of kidney damage and liver injury
appear. Kidney abnormalities may cause blood
appear. Kidney abnormalities may cause blood
in the urine and painful urination. Liver injury
in the urine and painful urination. Liver injury
tends to be mild and usually heals completely.
tends to be mild and usually heals completely.

23. Hepatitis - Leptospirosis
Hepatitis - Leptospirosis
Hepatitis is the
Hepatitis is the
frequent complication
frequent complication
Elevation of serum
Elevation of serum
creatine phosphilipae
creatine phosphilipae
enzyme raise
enzyme raise
differentiates from
differentiates from
Viral hepatitis where
Viral hepatitis where
the enxyme is not
the enxyme is not
raised
raised

24. Nephritis - Leptospirosis
Nephritis - Leptospirosis
Kidney involvement in
Kidney involvement in
animals produce chronic
animals produce chronic
disease of the kidney and
disease of the kidney and
the infected animal starts
the infected animal starts
shedding large number of
shedding large number of
leptospira and main
leptospira and main
source of environmental
source of environmental
contamination of bacteria
contamination of bacteria
and results I human
and results I human
infections
infections
Human urine also contain
Human urine also contain
Spirochetes in the second
Spirochetes in the second
and third week of infection
and third week of infection

25. Early and Prompt Diagnosis is
Early and Prompt Diagnosis is
Highly Essential
Highly Essential
The development of simpler, rapid assays
The development of simpler, rapid assays
for diagnosis has been based largely on
for diagnosis has been based largely on
the recognition that early initiation of
the recognition that early initiation of
antibiotic therapy is important in acute
antibiotic therapy is important in acute
disease but also on the need for assays
disease but also on the need for assays
which can be used more widely.
which can be used more widely.

26. Laboratory Diagnosis
Laboratory Diagnosis
Specimens
Specimens
1
1 Blood to be collected in a
Blood to be collected in a
heparin tube
heparin tube
2 CSF, Tissues
2 CSF, Tissues
Microscopic examination
Microscopic examination
3 Urine to be collected with
3 Urine to be collected with
great care to avoid
great care to avoid
contamination
contamination
4 Serum for agglutination
4 Serum for agglutination
tests
tests

27. Culturing Leptospira
Culturing Leptospira
Blood and Urine be cultured
Blood and Urine be cultured
in Fletcher’s semisolid
in Fletcher’s semisolid
agar or other media
agar or other media
chemically defined
chemically defined
protein-free media for the
protein-free media for the
growth of leptospires have
growth of leptospires have
been proposed. In order to
been proposed. In order to
obtain the desired rapid
obtain the desired rapid
and abundant growth of
and abundant growth of
organisms necessary for
organisms necessary for
the efficient production of
the efficient production of
vaccines, it has been
vaccines, it has been
necessary to supplement
necessary to supplement
such media with a source
such media with a source
of fatty acids,
of fatty acids,

28. Serology
Serology
Agglutinating
Agglutinating
antibodies raise to
antibodies raise to
very high titers
very high titers
1 : 10,000 or higher
1 : 10,000 or higher
occurs 5 – 10 weeks
occurs 5 – 10 weeks
after onset of infection
after onset of infection

29. Serology - ELISA
Serology - ELISA
Several
Several
Immunoassays are
Immunoassays are
available as
available as
commercial kits
commercial kits
Detection of IgM and
Detection of IgM and
razing titers of IgG will
razing titers of IgG will
guide in association
guide in association
with clinical history
with clinical history
will help in Diagnosis
will help in Diagnosis

30. Treatment
Treatment
Antibiotic of choice is
Antibiotic of choice is Benzyl Pencillin
Benzyl Pencillin
given by injection in doses of 5 mega units
given by injection in doses of 5 mega units
in a day, for 5 days.
in a day, for 5 days.
If the patients are genuinely hypertensive
If the patients are genuinely hypertensive
to Pencillin opted with Erythromycin
to Pencillin opted with Erythromycin
250mgs four times a day for a period of 5
250mgs four times a day for a period of 5
days.
days.

31. Treatment - Other alternatives
Treatment - Other alternatives
The leptospirosis can be effectively
The leptospirosis can be effectively
treated with
treated with
Doxycycline
Doxycycline
Ampicillin
Ampicillin
Amoxicillin
Amoxicillin
Severe patients need administration
Severe patients need administration
Intravenous Pencillin or Amoxcillin
Intravenous Pencillin or Amoxcillin

32. Epidemiology
Epidemiology
Leptospirosis causes several animal infections
Leptospirosis causes several animal infections
Most wide spread zoonotic infection in Nature
Most wide spread zoonotic infection in Nature
Human infections are accidental associated with
Human infections are accidental associated with
contamination of water, other materials
contamination of water, other materials
contaminated with excreta and animal flesh.
contaminated with excreta and animal flesh.
Animal carriers often excrete upto 100million
Animal carriers often excrete upto 100million
leptospirosis per ml of urine
leptospirosis per ml of urine

33. Epidemiology - Occupation
Epidemiology - Occupation
Ce rta in occupa tiona l
Ce rta in occupa tiona l
groups s uch a s
groups s uch a s
a griculture worke rs in
a griculture worke rs in
rice a nd ca ne fie lds ,
rice a nd ca ne fie lds ,
mine rs a nd s e ve r
mine rs a nd s e ve r
cle a ne rs a re pote ntia l
cle a ne rs a re pote ntia l
victims
victims

34. How Man gets Infected
How Man gets Infected
Water the great source
Water the great source
Drinking
Drinking
Swimming
Swimming
Bathing, as the urine of
Bathing, as the urine of
Rodents chronically
Rodents chronically
infected contaminate
infected contaminate
water sources
water sources
Children get infected
Children get infected
when in contact with
when in contact with
infected Dogs
infected Dogs

35. Control of Leptospirosis
Control of Leptospirosis
Rodent control is
Rodent control is
most important.
most important.
Human’s should avoid
Human’s should avoid
contact with water
contact with water
contaminated with
contaminated with
animal contact.
animal contact.

36. Chemoprophylaxis
Chemoprophylaxis
Doxycycline 200 mg
Doxycycline 200 mg
ora lly once a we e k is
ora lly once a we e k is
s imple e ffe ctive
s imple e ffe ctive
me a s ure . Whe n
me a s ure . Whe n
he a vy e xpos ure is
he a vy e xpos ure is
a nticipa te d
a nticipa te d

37. Vaccination in humans
Vaccination in humans
Vaccination for humans is justified where they
Vaccination for humans is justified where they
cannot be separated from animal sources or
cannot be separated from animal sources or
where the animals cannot be immunized
where the animals cannot be immunized
successfully
successfully
Necessity of human vaccinated will arise where
Necessity of human vaccinated will arise where
people live and work in proximity to rodents in
people live and work in proximity to rodents in
wet, tropical conditions, in wet rice planting and
wet, tropical conditions, in wet rice planting and
harvesting, in military operations, or working in
harvesting, in military operations, or working in
sewers.
sewers.
Ye t no univers a lly a cce pte d va ccine is a va ila ble
Ye t no univers a lly a cce pte d va ccine is a va ila ble
for huma ns
for huma ns

38. Vaccination of Animals
Vaccination of Animals
Vaccinating animals have a dual purpos e
Vaccinating animals have a dual purpos e
1 Protecting animals
1 Protecting animals
2 Protecting humans who may contract leptos piros is
2 Protecting humans who may contract leptos piros is
from them
from them
It is probably true as that immunization of animals will
It is probably true as that immunization of animals will
prevent leptos piros is in people in contact with them.
prevent leptos piros is in people in contact with them.
It proved true in 1980 when extens ive vaccination of
It proved true in 1980 when extens ive vaccination of
dairy cows in New Zealand lead to marked decreas ed
dairy cows in New Zealand lead to marked decreas ed
incidence in Humans .
incidence in Humans .
Animals immunized experimentally with polys accharide
Animals immunized experimentally with polys accharide
derived from Leptos pira LPS linked to diphtheria
derived from Leptos pira LPS linked to diphtheria
Toxoid were protected agains t challenges
Toxoid were protected agains t challenges
Several other vaccines in us e to s uit local needs .
Several other vaccines in us e to s uit local needs .

39. New Vaccine trails - Leptospira
New Vaccine trails - Leptospira

40. Cr e a t e d f or He a l t h
Cr e a t e d f or He a l t h
a wa r e ne s s on
a wa r e ne s s on
Le pt os pi r os i s
Le pt os pi r os i s
Dr.T.V.Rao MD
Dr.T.V.Rao MD
Email
Email
doctortvrao@gmail.com
doctortvrao@gmail.com