Q Fever PCR test
wildlife and zoo assay data sheet
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Q
fever
(etiologic agent:
Coxiella burnetii)
Test code:
B0066
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Ultrasensitive detection of
Coxiella burnetii by real time PCR
Q fever is a
zoonotic disease caused by Coxiella burnetii, an obligate
intracellular bacterium which lives only in nucleated cells and
is present ubiquitously in the environment.
Cattle, sheep,
and goats are the primary reservoirs of C. burnetii.
However, many other animals can be infected including other
species of livestock and pets. Infection of these animals does
not usually result in clinical symptoms, and even in goats and
sheep abortion is the major clinical symptom reported.
Infected
asymptomatic domestic animals can spread the disease to humans.
Infected animals can excrete the bacteria in milk, urine, and
feces. Most importantly, the organisms are shed in high numbers
in amniotic fluid and placenta during birthing.
C. burnetii
is highly resistant to heat, drying, and many common
disinfectants. It can survive for long periods in the
environment, and be transmitted to humans by inhalation of
aerosols and dust at farms and other animal facilities.
Humans are very
susceptible to the disease and inhalation of only very few
organisms is sufficient to cause infection. Ingestion of
contaminated milk or milk products can transmit the disease but
is not common. Transmission to humans can also occur
through tick bites. However, direct human to human
transmission is very rare.
Culture
detection of the bacteria is difficult and is not available in
most laboratories. Serological detection of the bacteria is
unreliable. For example, serum antibodies are detectable about 2
weeks after the initial infection of sheep. The antibody
concentrations reach a maximum at 30 to 60 days, then rapidly
decline and phase into the seasonal antibody cycle of the rest
of the flock in relation to the lambing season (McCaul et al,
1981). Therefore, if the infected sheep is tested by serology
during the low point of the cycle, when antibody concentration
is below the detectable level, it will be misleading to claim a
seronegative flock basing on the testing result.
Molecular
detection by PCR is unaffected by changes in the infection
cycle, and enables rapid, sensitive and specific detection of
C. burnetii in a sample (Panning et al., 2008).
Utilities:
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Help confirm the
disease causing agent
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Identify Q
fever carriers
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Help ensure that
animal facilities and populations are free of Q fever
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Early
prevention of spread of Q fever among animals
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Minimize
human exposure to Q fever
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Safety
monitoring of biological products that derive from animals
References:
McCaul, T.F., Hakstadt, T. and Williams, J.C. (1981)
Ultrastructural and biological aspects of
Coxiella burnetii
under physical disruptions. In: Burgdorfer W, Anacker RL, eds.
Rickettsiae and rickettsial diseases. New York: Harcourt Brace
Jovanovich, 1981.
Panning, M.,
Kilwinski, J., Greiner-Fischer, S., Peters, M., Kramme, S.,
Frangoulidis, D., Meyer, H., Henning, K. and Drosten, C. (2008)
High throughput detection of Coxiella burnetii by
real-time PCR with internal control system and automated DNA
preparation. BMC Microbiol. 8:77.
Specimen requirements:
Whole
blood in EDTA (purple top) tube, or rectal
swab or genital swab, or 0.2 ml feces, milk, urine, amniotic
fluid or aborted tissue.
Contact Zoologix if advice is needed to determine an appropriate specimen type for a specific diagnostic application. For specimen types not listed here, please contact Zoologix 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
Methodology:
Qualitative real time PCR
Normal range:
Nondetected
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