Tuberculosis hardly excuse anyone irrespective of its shape, size, colour, cast, creed, breed, species or genus having a little warmth in blood. Therefore, elephants e not exception, rather very prone for this disease which have taken many times more lives than any of the war.

1. ZOONOTIC TUBERCULOSIS in
ELEPHANTS
Dr Sakshi Dubey, MVSc. Scholar, Epidemiology
Dr. Bhoj R Singh, Principal Scientist & Head, Division of Epidemiolo
IVRI, Izanagar, Bareilly, UP, India

2. Tuberculosis
 One of the most ancient diseases of mankind and




animals
A contagious zoonotic disease
Aristotle was first to say that tuberculosis is an
airborne disease.
In 1865 Jean Antoine Villemin, put out the idea that TB
was genetically inherited.
In1882 Robert Koch proved Villemin wrong by
discovering the bacterium causing the disease. It is
caused by Mycobacterium spp.

3. Indian scenario
 Endemic in most parts.
 Holds about 21% of the total global TB
cases
 1000 Indians die from TB per day.
(Krishnaswami, 2000)
 One third of the population is suffering from
TB.

4. Global
Scenario
 2nd most common infectious cause of deaths
(WHO 2013)
 Human TB (zoonotic 3-10%) - localized in High
Burden Countries
(India, China, Indonesia, Nigeria, Bangladesh, a
nd Pakistan)
 22 High Burden Countries including India house
for 80 % of all new TB cases.
 In developing countries ~10.5% of human cases
are associated with M. Bovis (ILRI,2012).

5. The Global Burden of TB -2011
Estimated number
of cases
All forms of TB
8.7 million
(8.3–9.0 million)
Estimated number
of deaths
1.4 million*
(1.3–1.6 million)
Multidrug-resistant TB
1.1 million (13%)
430,000
(1.0–1.2 million)
HIV-associated TB
(400,000–460,000)
Up to 0.5 million
Unknown, but
probably > 150,000
Source: WHO Global Tuberculosis Report 2012
GLOBAL TB
PROGRAMME
* Including deaths attributed to HIV/TB

6. Incidence rates, 2011 ( WHO )
0–24
25–49
50–149
150–299
≥300
Per 100 000 population
Highest rates in Africa, linked to high rates of HIV infection
~80% of HIV+ TB cases in Africa

7. Prevalence in
Animal
Overall, 7.4% of livestock
Bovines: 8%,
camels 11%,
Sheep and goats 2%
Pigs 15%,
Wildlife 5%
(ILRI,2012)

8. Tuberculosis in wild animals
 A number of cases reported among wild animals
worldwide.
 In zoo primates TB is due to M. tuberculosis and
M. bovis
 In Larger land mammals (Ungulates), TB is
mostly caused by M. bovis.
 M. tuberculosis is the main cause of TB in
Elephants, Rhinoceroses, Tapirs, and in some
exotic bovine spp.

9. Tuberculosis in wild animals
 TB in a chimpanzee at London zoo reported by Owen
(1961)
 TB in Tigers of Delhi and Darjeeling Zoos (Rathore and
Khera, 1981)
 TB in Lions of zoological garden Bombay (Das and
Jayaro, 1986)
 M. tuberculosis reported in some exotic carnivores
and Psittacine birds.

10. Tuberculosis in wild
animals
Eurasian badger (Meles meles) UK
White-tailed deer (Odocoileus virginianus)
Wildlife
Reservoirs of
TB
Wild boar (Sus scrofa) Sp
Cape buffalo (Syncerus caffer) Africa
(Wilson et al., 2009)
Brush-tailed possum (Trichosurus vulpecula) New

11. Tuberculosis in Elephants
 Described in Asian documents of over 2000 years
old
 1st report of TB in elephants made in London
zoo in 1875
 Sporadic TB in Asian elephants and 1st case in
African elephant reported in mid 20th century
(Gorovitz, 1962)
 During 1997 transmission of TB between human
and elephants reported
(Michalak et al., 1998)

12. Epidemiology
 Though it is also found in free ranging animals, tuberculosis
found more commonly in captive animal worldwide.
 In Asian elephants mostly M. tuberculosis and M. bovis are
involved.
(Abraham et al., 2010 and Mikota et al., 2007)
 Female seems to be affected more than the male elephants
(Karthik, 2012)
 Prevalence of TB in Asian elephants is about 15% in India
and 13% in Nepal
(Abraham et al., 2010 and Mikota et
al., 2007)
 In United States of America (USA), its prevalence in
elephants is 6.3%

13. Transmission to
elephants
 Humans activity can lead to an increased level of
M. tuberculosis being shed into the environment
and may result in the spillover of infection into
wildlife populations
(Mikota, 2008)

14. Development of TB
Inhalation of bacteria
Bacteria reach lungs, enter macrophages
Bacteria reproduce in macrophages
Lesion begins to form
(caseous necrosis)
Activated macrophages
Bacteria cease to grow;
lesion calcifies
Immune
suppression
Lesion liquifies
Spread to
blood,organs
reactivation
death
Bact coughed up
in sputum

15. Clinical signs
 No typical signs in elephant
 Non specific signs includes:
 Inappetance
 Weight loss
 Subcutaneous ventral oedema
(Kay et. al. 2010)

16. Zoonotic aspects
 By aerosolization my spread to:
 Elephant handlers
 Zoo employees, veterinarians
 Other animals

17. Pathology
 Involves primarily :
 Lungs
 Thoracic & Bronchial lymph nodes
 Extra thoracic sites
 Caseous and mucopurulent exudates in trunk
Histological findings:
Epethelioid granulomas with giant cell
Pyelogranulomatous pneumonia

18. Diagnosis
 Intra-dermal Tuberculin Test
 Microscopic examination
 Acid Fast Staining
 Serological test
 Elephant TB STAT-PAK® Assay
 Multi-antigen print immunoassay (MAPIA)
 ELISA
 Molecular test
PCR

19.  Isolation and identification of Mycobacterium species
 Sample: Trunk wash, Blood/Serum
 “Triple sample method”
 Lowenstein Jensen medium

20. TREATMENT
Dose and route of administration of Anti-Tubercular drugs in
Elephants Route
S. No.
Drug
Does
Target conc.
1.
2.
3.
4.
Ethambutol
Isoniazid
Pyrazinamide
Rifampin
(mg/kg)
30
5
30
10
Oral
Oral/rectal
Oral/rectal
Oral
(µg/ml)
2-5
3-5
20-60
8-24
(Guideline for control of tuberculosis, 2008 and Peloquin et al., 2006)
• Standard protocol includes:
• 2 months with Isoniazid, Rifampin, Pyranzinamide &
Ethambutol
• followed by 4 months of isoniazid and rifampicin
(Daly et
al., 2006)

21. Tuberculosis Management
Options

23. Conclusion
 TB is endemic in captive elephants
 The role played by elephants in the spread of TB
to humans needs to be addressed.
 Regular screening of elephants for TB is required
for control.
 Research on tuberculosis in elephants is required