S0081 - Ultrasensitive qualitative detection of yellow
fever virus by reverse transcription coupled real time
polymerase chain reaction.
Yellow fever occurs frequently in tropical regions of Africa and
South America. The virus belongs to the Flaviviridae family,
Flavivirus genus (Monath and Heinz, 1996). Mosquitos carry the
virus from one host to another, primarily between monkeys, from
monkeys to humans, and from person to person. Transmission to
humans commonly occurs in forest transition zones; the disease
may enter into populated urban areas through the spread of the
mosquito vector. Many tropical cities are now facing yellow
fever epidemics because of unhygienic living conditions allowing
mosquitos to breed there.
Patients infected with yellow fever virus can develop acute
onset of fever followed by jaundice within two weeks of onset of
first symptoms and bleeding from nose, gums, skin, or
gastrointestinal tract. Death may occur within 3 weeks of onset
of severe illness. Up to 50% of severely affected patients die
from yellow fever. There is no cure for yellow fever; treatment
is palliative only.
Yellow fever is difficult to diagnose, especially during the
early stages. It can be confused with severe malaria, dengue
hemorrhagic fever, leptospirosis, viral hepatitis, hemorrhagic
fevers and other diseases, as well as poisoning.
Traditional laboratory methods of diagnosing yellow fever
include culture isolation of the yellow fever virus; or the
presence of yellow fever specific IgM; or a four-fold or greater
rise in serum IgG levels (acute or convalescent); or positive
post-mortem liver histopathology; or detection of yellow fever
viral antigen in tissues by immunohistochemistry.
More recently, the detection of yellow fever virus
genomic sequences in blood or organs by polymerase chain
reaction (PCR) has become a useful diagnostic tool. Diagnosis by
PCR is now often preferred because of its speed, high
specificity and sensitivity.
Help confirm the disease causing agent
Shorten the time required to confirm a clinical diagnosis of
Help ensure that primate colonies are free of yellow fever
Early prevention of spread of this virus
Minimize personnel exposure to this virus
Monath TP, Heinz FX (1996) Flaviviruses. In Fields BN, Knipe DM,
Howley PM et al. (eds): ‘‘Fields Virology.’’ Philadelphia:
Lippincott-Raven Press Publishers, pp 961–1034.
Specimen requirements: 0.2 ml whole blood
in EDTA (purple top) or ACD (yellow top) tube, or 0.2 ml serum
or plasma, or 0.2 ml fresh or frozen tissue.
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.
2 business days
transcription coupled real time PCR
Normal range: Nondetected