wildlife and zoo assay data sheet
Tuberculosis and other mycobacteria in
mammals
Test
codes:
B0015
- Ultrasensitive qualitative detection of
Mycobacterium tuberculosis ("M.tb")
complex by real time polymerase chain reaction.
Assay detects but does not differentiate
M. tuberculosis, M. bovis and M. microti. Assay does not detect other mycobacteria
species.
B0029
- Ultrasensitive qualitative detection of
Mycobacterium avium,
subspecies avium
by real time polymerase chain reaction. Assay does not detect
subspecies paratuberculosis
or other mycobacteria species.
B0030
- Ultrasensitive qualitative detection of
Mycobacterium avium,
subspecies
paratuberculosis (Johne's disease) by real
time polymerase chain reaction. Assay does not detect subspecies
avium or other
mycobacteria species.
B0031
- Ultrasensitive qualitative detection of
Mycobacterium intracellulare
by real time polymerase chain reaction. Assay does not detect
other mycobacteria species.
B0067
- Ultrasensitive qualitative detection
and differentiation of
Mycobacterium tuberculosis
and Mycobacterium bovis
by real time polymerase chain reaction. Assay does not detect other mycobacteria
species.
P0006
- Ultrasensitive qualitative
mycobacteria
screen by nested
polymerase chain reaction.
Assay
detects but does not
differentiate a wide range of mycobacteria,
including M. tuberculosis,
M. bovis, M. microti, M. intracellulare, M. avium, M. gastri, M.
africanum, M. scrofulaceum, M. ulcerans, M. simiae, M. kansasii,
M. chelonae, M. fortuitum, M. marinum, M. genavense
and others.
P0007
- Ultrasensitive qualitative
mycobacteria
species identification
by nested polymerase chain reaction and Restriction Fragment
Length Polymorphism. This 2-stage assay detects and
differentiates a wide range of mycobacteria, including
M. tuberculosis/bovis/microti ("M.tb
complex"), M. avium, M. intracellulare, M. africanum, M. gastri,
M. scrofulaceum, M. ulcerans, M. simiae, M. kansasii, M.
chelonae,
M. fortuitum,
M. marinum, M.
genavense
and others.
Many
different mycobacteria can cause disease in
mammals. Mammals acquire classic tuberculosis (TB) by contact
with other infected nonhuman primates or humans through
inhalation or the digestive route (Moreland, 1970). These
infected animals can become reservoirs, causing outbreaks of
disease. TB infections have also been reported in many other
captive and wildlife species.
The main
etiologic agents of TB in primates are
Mycobacterium tuberculosis, M.
bovis, M. africanum and M. microti, and infection by
these mycobacteria usually results in pulmonary manifestations
and occasionally disseminated disease. Mycobacteria other than
tuberculosis (MOTT) have also been implicated in monkey disease,
mainly acute and chronic enteropathies and pulmonary infections.
Asymptomatic infections by
M. avium, M. intracellulariae, M. scrofulaceum and
M. simiae have
also been reported (Calmette et al., 1923; Smith et al., 1973;
Renquist and Potkay, 1979; Brammer et al., 1995). Other
saprophyte MOTT have also been isolated from primates but are
usually not associated with disease.
Clinical
diagnosis of TB in primates can be difficult because infected
monkeys may only show mild behavioral changes like anorexia and
lethargy. Occasionally, infected monkeys may suddenly die while
appearing to be in good condition. The use of skin tests to
identify infected monkeys is somewhat unreliable because
mycobacteria-infected primates, even within the same species,
can have a wide range of responses to tuberculin injection, from
negative to strong positive reactions. In addition, skin tests
perform inconsistently across closely-related primate species,
notably the various species of macaques commonly kept in
captivity.
Detection of
TB and other mycobacterial infections in primates and other
species has relied on tuberculin skin response, serological
testing, histopathology, microscopy and culture identification.
Among these, the most frequently used methods are culture
identification and the tuberculin skin test (also known as the
PPD, for Purified Protein Derivative), the latter being a
routine test in quarantine and preventive medicine protocols
(Fowler, 1993). However, the PPD test is not adequately
sensitive or specific in many species and the rate of false
negatives is high. Culture and associated biochemical tests for
the identification of mycobacteria species are slow and
painstaking procedures, and require careful collection and
preservation of specimens in order to obtain accurate results.
PCR
detection of mycobacterial DNA is highly sensitive when proper
specimens are carefully collected. Sample types and collection
techniques vary by species; deep respiratory samples obtained
using bronchial lavage are often preferred for primates. Gastric
lavage can also be a useful sampling technique. Pathology
samples should be taken from foci most likely to contain the
pathogen -- typically lung or other organ lesions, or enlarged
lymph nodes. Trunk washes are used to obtain samples from
elephants (National Tuberculosis Working Group for Zoo and
Wildlife Species, 2003).
In addition
to the detection of a number of mycobacterial species by real
time PCR, identification of mycobacteria to the species level
can be accomplished rapidly through sequence analysis of PCR
products using a restriction fragment length polymorphism (RFLP)
technique. Ultrasensitive detection of mycobacteria by PCR and
subsequent restriction digest analysis not only allows reliable
detection of various species of mycobacteria but in many cases
also enables identification of mycobacteria at the species
level.
Utilities:
-
Confirm the disease causing agent
-
Ensure that animal groups and populations are free of
tuberculosis or other disease-causing mycobacteria
-
Early prevention of spread of mycobacteria among a
population
-
Minimize human exposure to disease-causing mycobacteria
References:
Brammer, D.W., O’Rourke, C.M., Heath, L.A., Chrisp, C.E., Peter,
G.K. and Hofing, G.L. (1995) Mycobacterium kansasii infection in
squirrel monkeys (Saimiri sciureus sciureus). J. Med. Primatol.
24: 231-235.
Calmette, A., Smith, G.H. and Soper, W.B.(1923)
Tubercle Bacillus Infection and Tuberculosis in Man and Animals,
Processes of Infection and Resistance, vol. Xxiii. Williams and
Wilkins Company, Baltimore, 689 pp.
Fowler, M.E. (1993) Zoo &
Animal Medicine: Current Therapy, 3rd ed., vol. xxv. Saunders,
Philadelphia, 617 pp.
Moreland, A.F. (1970) Tuberculosis in
New World primates. Lab. Anim. Care 20: 262-264.
Renquist,
D.M. and Potkay, S. (1979) Mycobacterium scrofulaceum infection
in Erythrocebus patas monkeys. Lab. Anim. Sci. 29: 97-101.
Smith, E.K., Hunt, R.D., Garcia, F.G., Fraser, C.E., Merkal,
R.S., Karlson, A.G. (1973) Avian tuberculosis in monkeys. A
unique mycobacterial infection. Am. Rev. Respir. Dis. 107:
469-471.
National
Tuberculosis Working Group for Zoo and Wildlife Species (2003).
Guidelines for the Control of Tuberculosis in Elephants.
USDA-APHIS: http://www.aphis.usda.gov/ac/TBGuidelines2003.pdf
Specimen requirements:
Excised lesion
from lung or other organ, or granuloma, or 0.5 ml lymph node
tissue,
or 0.5 ml bronchoalveolar lavage or gastric lavage, or 0.5 ml
trunk lavage (elephants).
For specimen
types other than those listed here, please call to confirm
specimen acceptability and shipping instructions.
For all
specimen types, if there will be a delay in shipping, or during
very warm weather, refrigerate specimens until shipped and ship
with a cold pack unless more stringent shipping requirements are
specified. Frozen specimens should be shipped so as to remain
frozen in transit. See shipping
instructions for more information.
Turnaround time:
2 business days (3 business days for P0007).
Methodologies:
B0015, B0029, B0030,
B0031 and
B0067: Qualitative real time PCR
P0006:
Qualitative nested PCR
P0007:
Qualitative nested PCR and RFLP
Normal range:
Nondetected